trying to organize files and use declarations

21 files changed, 2227 insertions, 0 deletions

diff --git a/src/attributes/arrow_type.rs b/src/attributes/arrow_type.rs
new file mode 100644
index 0000000..ac2d49f
--- /dev/null
+++ b/src/attributes/arrow_type.rs
@@ -0,0 +1,50 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum ArrowType {
+    Normal,
+    Dot,
+    Odot,
+    None,
+    Empty,
+    Diamond,
+    Ediamond,
+    Box,
+    Open,
+    Vee,
+    Inv,
+    Invdot,
+    Invodot,
+    Tee,
+    Invempty,
+    Odiamond,
+    Crow,
+    Obox,
+    Halfopen,
+}
+
+impl<'a> DotString<'a> for ArrowType {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            ArrowType::Normal => "normal".into(),
+            ArrowType::Dot => "dot".into(),
+            ArrowType::Odot => "odot".into(),
+            ArrowType::None => "none".into(),
+            ArrowType::Empty => "empty".into(),
+            ArrowType::Diamond => "diamond".into(),
+            ArrowType::Ediamond => "ediamond".into(),
+            ArrowType::Box => "box".into(),
+            ArrowType::Open => "open".into(),
+            ArrowType::Vee => "vee".into(),
+            ArrowType::Inv => "inv".into(),
+            ArrowType::Invdot => "invdot".into(),
+            ArrowType::Invodot => "invodot".into(),
+            ArrowType::Tee => "tee".into(),
+            ArrowType::Invempty => "invempty".into(),
+            ArrowType::Odiamond => "odiamond".into(),
+            ArrowType::Crow => "crow".into(),
+            ArrowType::Obox => "obox".into(),
+            ArrowType::Halfopen => "halfopen".into(),
+        }
+    }
+}
diff --git a/src/attributes/cluster_mode.rs b/src/attributes/cluster_mode.rs
new file mode 100644
index 0000000..03e2bf9
--- /dev/null
+++ b/src/attributes/cluster_mode.rs
@@ -0,0 +1,18 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum ClusterMode {
+    Local,
+    Global,
+    None,
+}
+
+impl<'a> DotString<'a> for ClusterMode {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            ClusterMode::Local => "local".into(),
+            ClusterMode::Global => "global".into(),
+            ClusterMode::None => "none".into(),
+        }
+    }
+}
diff --git a/src/attributes/color.rs b/src/attributes/color.rs
new file mode 100644
index 0000000..92a26eb
--- /dev/null
+++ b/src/attributes/color.rs
@@ -0,0 +1,165 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+#[derive(Copy, Clone, PartialEq, Debug)]
+pub enum Color<'a> {
+    RGB {
+        red: u8,
+        green: u8,
+        blue: u8,
+    },
+    RGBA {
+        red: u8,
+        green: u8,
+        blue: u8,
+        alpha: u8,
+    },
+    // TODO: constrain?
+    // Hue-Saturation-Value (HSV) 0.0 <= H,S,V <= 1.0
+    HSV {
+        hue: f32,
+        saturation: f32,
+        value: f32,
+    },
+    Named(&'a str),
+}
+
+impl<'a> DotString<'a> for Color<'a> {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Color::RGB { red, green, blue } => {
+                format!("#{:02x?}{:02x?}{:02x?}", red, green, blue).into()
+            }
+            Color::RGBA {
+                red,
+                green,
+                blue,
+                alpha,
+            } => {
+                format!("#{:02x?}{:02x?}{:02x?}{:02x?}", red, green, blue, alpha).into()
+            }
+            Color::HSV {
+                hue,
+                saturation,
+                value,
+            } => format!("{} {} {}", hue, saturation, value).into(),
+            Color::Named(color) => (*color).into(),
+        }
+    }
+}
+
+// The sum of the optional weightings must sum to at most 1.
+pub struct WeightedColor<'a> {
+    pub color: Color<'a>,
+
+    // TODO: constrain
+    /// Must be in range 0 <= W <= 1.
+    pub weight: Option<f32>,
+}
+
+impl<'a> DotString<'a> for WeightedColor<'a> {
+    fn dot_string(&self) -> Cow<'a, str> {
+        let mut dot_string = self.color.dot_string().to_string();
+        if let Some(weight) = &self.weight {
+            dot_string.push_str(format!(";{}", weight).as_str());
+        }
+        dot_string.into()
+    }
+}
+
+pub struct ColorList<'a> {
+    pub colors: Vec<WeightedColor<'a>>,
+}
+
+impl<'a> DotString<'a> for ColorList<'a> {
+    /// A colon-separated list of weighted color values: WC(:WC)* where each WC has the form C(;F)?
+    /// Ex: fillcolor=yellow;0.3:blue
+    fn dot_string(&self) -> Cow<'a, str> {
+        let mut dot_string = String::new();
+        let mut iter = self.colors.iter();
+        let first = iter.next();
+        if first.is_none() {
+            return dot_string.into();
+        }
+        dot_string.push_str(&first.unwrap().dot_string());
+        for weighted_color in iter {
+            dot_string.push_str(":");
+            dot_string.push_str(&weighted_color.dot_string())
+        }
+
+        dot_string.into()
+    }
+}
+
+/// Convert an element like `(i, j)` into a WeightedColor
+pub trait IntoWeightedColor<'a> {
+    fn into_weighted_color(self) -> WeightedColor<'a>;
+}
+
+impl<'a> IntoWeightedColor<'a> for &(Color<'a>, Option<f32>) {
+    fn into_weighted_color(self) -> WeightedColor<'a> {
+        let (s, t) = *self;
+        WeightedColor {
+            color: s,
+            weight: t,
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::{Color, ColorList, WeightedColor};
+    use crate::DotString;
+
+    #[test]
+    fn colorlist_dot_string() {
+        let yellow = WeightedColor {
+            color: Color::Named("yellow"),
+            weight: Some(0.3),
+        };
+
+        let blue = WeightedColor {
+            color: Color::Named("blue"),
+            weight: None,
+        };
+
+        let color_list = ColorList {
+            colors: vec![yellow, blue],
+        };
+
+        let dot_string = color_list.dot_string();
+
+        assert_eq!("yellow;0.3:blue", dot_string);
+    }
+
+    #[test]
+    fn color_rbg_dot_string() {
+        let color = Color::RGB {
+            red: 160,
+            green: 82,
+            blue: 45,
+        };
+        assert_eq!("#a0522d", color.dot_string());
+    }
+
+    #[test]
+    fn color_rbga_dot_string() {
+        let color = Color::RGBA {
+            red: 160,
+            green: 82,
+            blue: 45,
+            alpha: 10,
+        };
+        assert_eq!("#a0522d0a", color.dot_string());
+    }
+
+    #[test]
+    fn color_hsv_dot_string() {
+        let color = Color::HSV {
+            hue: 0.051,
+            saturation: 0.718,
+            value: 0.627,
+        };
+        assert_eq!("0.051 0.718 0.627", color.dot_string());
+    }
+}
diff --git a/src/attributes/compass_point.rs b/src/attributes/compass_point.rs
new file mode 100644
index 0000000..3ebb250
--- /dev/null
+++ b/src/attributes/compass_point.rs
@@ -0,0 +1,41 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+// TODO: not sure we need this enum but should support setting nodeport either via
+// headport / tailport attributes e.g. a -> b [tailport=se]
+// or via edge declaration using the syntax node name:port_name e.g. a -> b:se
+// aka compass
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum CompassPoint {
+    N,
+    NE,
+    E,
+    SE,
+    S,
+    SW,
+    W,
+    NW,
+    C,
+    // TODO: none might not be a good name
+    // The compass point "_" specifies that an appropriate side of the port adjacent to the exterior
+    // of the node should be used, if such exists. Otherwise, the center is used.
+    // If no compass point is used with a portname, the default value is "_".
+    None,
+}
+
+impl<'a> DotString<'a> for CompassPoint {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            CompassPoint::N => "n".into(),
+            CompassPoint::NE => "ne".into(),
+            CompassPoint::E => "e".into(),
+            CompassPoint::SE => "se".into(),
+            CompassPoint::S => "s".into(),
+            CompassPoint::SW => "sw".into(),
+            CompassPoint::W => "w".into(),
+            CompassPoint::NW => "nw".into(),
+            CompassPoint::C => "c".into(),
+            CompassPoint::None => "_".into(),
+        }
+    }
+}
diff --git a/src/attributes/direction.rs b/src/attributes/direction.rs
new file mode 100644
index 0000000..bebc3c0
--- /dev/null
+++ b/src/attributes/direction.rs
@@ -0,0 +1,20 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum Direction {
+    Forward,
+    Back,
+    Both,
+    None,
+}
+
+impl<'a> DotString<'a> for Direction {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Direction::Forward => "forward".into(),
+            Direction::Back => "back".into(),
+            Direction::Both => "both".into(),
+            Direction::None => "none".into(),
+        }
+    }
+}
diff --git a/src/attributes/image.rs b/src/attributes/image.rs
new file mode 100644
index 0000000..360191a
--- /dev/null
+++ b/src/attributes/image.rs
@@ -0,0 +1,46 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum ImagePosition {
+    TopLeft,
+    TopCentered,
+    TopRight,
+    MiddleLeft,
+    MiddleCentered,
+    MiddleRight,
+    BottomLeft,
+    BottomCentered,
+    BottomRight,
+}
+
+impl<'a> DotString<'a> for ImagePosition {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            ImagePosition::TopLeft => "tl".into(),
+            ImagePosition::TopCentered => "tc".into(),
+            ImagePosition::TopRight => "tr".into(),
+            ImagePosition::MiddleLeft => "ml".into(),
+            ImagePosition::MiddleCentered => "mc".into(),
+            ImagePosition::MiddleRight => "mr".into(),
+            ImagePosition::BottomLeft => "bl".into(),
+            ImagePosition::BottomCentered => "bc".into(),
+            ImagePosition::BottomRight => "br".into(),
+        }
+    }
+}
+
+pub enum ImageScale {
+    Width,
+    Height,
+    Both,
+}
+
+impl<'a> DotString<'a> for ImageScale {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            ImageScale::Width => "width".into(),
+            ImageScale::Height => "height".into(),
+            ImageScale::Both => "both".into(),
+        }
+    }
+}
diff --git a/src/attributes/label.rs b/src/attributes/label.rs
new file mode 100644
index 0000000..e62de2b
--- /dev/null
+++ b/src/attributes/label.rs
@@ -0,0 +1,34 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum LabelJustification {
+    Left,
+    Right,
+    Center,
+}
+
+impl<'a> DotString<'a> for LabelJustification {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            LabelJustification::Left => "l".into(),
+            LabelJustification::Right => "r".into(),
+            LabelJustification::Center => "c".into(),
+        }
+    }
+}
+
+pub enum LabelLocation {
+    Top,
+    Center,
+    Bottom,
+}
+
+impl<'a> DotString<'a> for LabelLocation {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            LabelLocation::Top => "t".into(),
+            LabelLocation::Center => "c".into(),
+            LabelLocation::Bottom => "b".into(),
+        }
+    }
+}
diff --git a/src/attributes/mod.rs b/src/attributes/mod.rs
new file mode 100644
index 0000000..d01d246
--- /dev/null
+++ b/src/attributes/mod.rs
@@ -0,0 +1,1182 @@
+mod arrow_type;
+mod cluster_mode;
+mod color;
+mod compass_point;
+mod direction;
+mod image;
+mod label;
+mod ordering;
+mod output_mode;
+mod pack_mode;
+mod page_direction;
+mod point;
+mod port_position;
+mod rankdir;
+mod ratio;
+mod rectangle;
+mod shape;
+mod spline_type;
+mod splines;
+mod style;
+
+pub use crate::attributes::arrow_type::ArrowType;
+pub use crate::attributes::cluster_mode::ClusterMode;
+pub use crate::attributes::color::{Color, ColorList, IntoWeightedColor, WeightedColor};
+pub use crate::attributes::compass_point::CompassPoint;
+pub use crate::attributes::direction::Direction;
+pub use crate::attributes::image::{ImagePosition, ImageScale};
+pub use crate::attributes::label::{LabelJustification, LabelLocation};
+pub use crate::attributes::ordering::Ordering;
+pub use crate::attributes::output_mode::OutputMode;
+pub use crate::attributes::pack_mode::PackMode;
+pub use crate::attributes::page_direction::PageDirection;
+pub use crate::attributes::point::Point;
+pub use crate::attributes::port_position::PortPosition;
+pub use crate::attributes::rankdir::RankDir;
+pub use crate::attributes::ratio::Ratio;
+pub use crate::attributes::rectangle::Rectangle;
+pub use crate::attributes::shape::Shape;
+pub use crate::attributes::spline_type::SplineType;
+pub use crate::attributes::splines::Splines;
+pub use crate::attributes::style::{EdgeStyle, GraphStyle, NodeStyle, Styles};
+pub use crate::attributes::AttributeText::{AttrStr, EscStr, HtmlStr, QuotedStr};
+use crate::dot::DotString;
+use indexmap::map::IndexMap;
+use std::borrow::Cow;
+use std::collections::HashMap;
+
+/// The text for a graphviz label on a node or edge.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum AttributeText<'a> {
+    /// Preserves the text directly as is.
+    AttrStr(Cow<'a, str>),
+
+    /// This kind of label uses the graphviz label escString type:
+    /// <http://www.graphviz.org/doc/info/attrs.html#k:escString>
+    ///
+    /// Occurrences of backslashes (`\`) are not escaped; instead they
+    /// are interpreted as initiating an escString escape sequence.
+    ///
+    /// Escape sequences of particular interest: in addition to `\n`
+    /// to break a line (centering the line preceding the `\n`), there
+    /// are also the escape sequences `\l` which left-justifies the
+    /// preceding line and `\r` which right-justifies it.
+    EscStr(Cow<'a, str>),
+
+    /// This uses a graphviz [HTML string label][html].
+    /// The string is printed exactly as given, but between `<` and `>`.
+    /// **No escaping is performed.**
+    ///
+    /// [html]: https://graphviz.org/doc/info/shapes.html#html
+    HtmlStr(Cow<'a, str>),
+
+    /// Preserves the text directly as is but wrapped in quotes.
+    ///
+    /// Occurrences of backslashes (`\`) are escaped, and thus appear
+    /// as backslashes in the rendered label.
+    QuotedStr(Cow<'a, str>),
+}
+
+impl<'a> AttributeText<'a> {
+    pub fn attr<S: Into<Cow<'a, str>>>(s: S) -> AttributeText<'a> {
+        AttrStr(s.into())
+    }
+
+    pub fn escaped<S: Into<Cow<'a, str>>>(s: S) -> AttributeText<'a> {
+        EscStr(s.into())
+    }
+
+    pub fn html<S: Into<Cow<'a, str>>>(s: S) -> AttributeText<'a> {
+        HtmlStr(s.into())
+    }
+
+    pub fn quoted<S: Into<Cow<'a, str>>>(s: S) -> AttributeText<'a> {
+        QuotedStr(s.into())
+    }
+
+    fn escape_char<F>(c: char, mut f: F)
+    where
+        F: FnMut(char),
+    {
+        match c {
+            // not escaping \\, since Graphviz escString needs to
+            // interpret backslashes; see EscStr above.
+            '\\' => f(c),
+            _ => {
+                for c in c.escape_default() {
+                    f(c)
+                }
+            }
+        }
+    }
+
+    fn escape_str(s: &str) -> String {
+        let mut out = String::with_capacity(s.len());
+        for c in s.chars() {
+            AttributeText::escape_char(c, |c| out.push(c));
+        }
+        out
+    }
+
+    /// Renders text as string suitable for a attribute in a .dot file.
+    /// This includes quotes or suitable delimiters.
+    pub fn dot_string(&self) -> String {
+        match *self {
+            AttrStr(ref s) => format!("{}", s),
+            EscStr(ref s) => format!("\"{}\"", AttributeText::escape_str(&s)),
+            HtmlStr(ref s) => format!("<{}>", s),
+            QuotedStr(ref s) => format!("\"{}\"", s.escape_default()),
+        }
+    }
+}
+
+impl<'a> From<ArrowType> for AttributeText<'a> {
+    fn from(arrow_type: ArrowType) -> Self {
+        AttributeText::attr(arrow_type.dot_string())
+    }
+}
+
+impl<'a> From<bool> for AttributeText<'a> {
+    fn from(v: bool) -> Self {
+        AttributeText::attr(v.to_string())
+    }
+}
+
+impl<'a> From<ClusterMode> for AttributeText<'a> {
+    fn from(mode: ClusterMode) -> Self {
+        AttributeText::quoted(mode.dot_string())
+    }
+}
+
+impl<'a> From<Color<'a>> for AttributeText<'a> {
+    fn from(color: Color<'a>) -> Self {
+        AttributeText::quoted(color.dot_string())
+    }
+}
+
+impl<'a> From<ColorList<'a>> for AttributeText<'a> {
+    fn from(color_list: ColorList<'a>) -> Self {
+        AttributeText::quoted(color_list.dot_string())
+    }
+}
+
+impl<'a> From<CompassPoint> for AttributeText<'a> {
+    fn from(compass: CompassPoint) -> Self {
+        AttributeText::quoted(compass.dot_string())
+    }
+}
+
+impl<'a> From<Direction> for AttributeText<'a> {
+    fn from(direction: Direction) -> Self {
+        AttributeText::attr(direction.dot_string())
+    }
+}
+
+impl<'a> From<EdgeStyle> for AttributeText<'a> {
+    fn from(style: EdgeStyle) -> Self {
+        AttributeText::attr(style.dot_string())
+    }
+}
+
+impl<'a> From<f32> for AttributeText<'a> {
+    fn from(v: f32) -> Self {
+        AttributeText::attr(v.to_string())
+    }
+}
+
+impl<'a> From<GraphStyle> for AttributeText<'a> {
+    fn from(style: GraphStyle) -> Self {
+        AttributeText::attr(style.dot_string())
+    }
+}
+
+impl<'a> From<ImagePosition> for AttributeText<'a> {
+    fn from(pos: ImagePosition) -> Self {
+        AttributeText::quoted(pos.dot_string())
+    }
+}
+
+impl<'a> From<ImageScale> for AttributeText<'a> {
+    fn from(scale: ImageScale) -> Self {
+        AttributeText::quoted(scale.dot_string())
+    }
+}
+
+impl<'a> From<LabelJustification> for AttributeText<'a> {
+    fn from(label_justification: LabelJustification) -> Self {
+        AttributeText::attr(label_justification.dot_string())
+    }
+}
+
+impl<'a> From<LabelLocation> for AttributeText<'a> {
+    fn from(label_location: LabelLocation) -> Self {
+        AttributeText::attr(label_location.dot_string())
+    }
+}
+
+impl<'a> From<NodeStyle> for AttributeText<'a> {
+    fn from(style: NodeStyle) -> Self {
+        AttributeText::attr(style.dot_string())
+    }
+}
+
+impl<'a> From<Ordering> for AttributeText<'a> {
+    fn from(ordering: Ordering) -> Self {
+        AttributeText::quoted(ordering.dot_string())
+    }
+}
+
+impl<'a> From<OutputMode> for AttributeText<'a> {
+    fn from(mode: OutputMode) -> Self {
+        AttributeText::quoted(mode.dot_string())
+    }
+}
+
+impl<'a> From<PackMode> for AttributeText<'a> {
+    fn from(mode: PackMode) -> Self {
+        AttributeText::quoted(mode.dot_string())
+    }
+}
+
+impl<'a> From<PageDirection> for AttributeText<'a> {
+    fn from(page_direction: PageDirection) -> Self {
+        AttributeText::attr(page_direction.dot_string())
+    }
+}
+
+impl<'a> From<Point> for AttributeText<'a> {
+    fn from(point: Point) -> Self {
+        AttributeText::quoted(point.dot_string())
+    }
+}
+
+impl<'a> From<PortPosition> for AttributeText<'a> {
+    fn from(port_position: PortPosition) -> Self {
+        AttributeText::quoted(port_position.dot_string())
+    }
+}
+
+impl<'a> From<RankDir> for AttributeText<'a> {
+    fn from(rank_dir: RankDir) -> Self {
+        AttributeText::attr(rank_dir.dot_string())
+    }
+}
+
+impl<'a> From<Ratio> for AttributeText<'a> {
+    fn from(ratio: Ratio) -> Self {
+        match ratio {
+            Ratio::Aspect(_aspect) => AttributeText::attr(ratio.dot_string()),
+            _ => AttributeText::quoted(ratio.dot_string()),
+        }
+    }
+}
+
+impl<'a> From<Rectangle> for AttributeText<'a> {
+    fn from(rectangle: Rectangle) -> Self {
+        AttributeText::quoted(rectangle.dot_string())
+    }
+}
+
+impl<'a> From<Shape> for AttributeText<'a> {
+    fn from(shape: Shape) -> Self {
+        AttributeText::attr(shape.dot_string())
+    }
+}
+
+impl<'a> From<Splines> for AttributeText<'a> {
+    fn from(splines: Splines) -> Self {
+        AttributeText::quoted(splines.dot_string())
+    }
+}
+
+impl<'a> From<SplineType> for AttributeText<'a> {
+    fn from(spline_type: SplineType) -> Self {
+        AttributeText::quoted(spline_type.dot_string())
+    }
+}
+
+impl<'a> From<Styles> for AttributeText<'a> {
+    fn from(styles: Styles) -> Self {
+        match styles {
+            Styles::Edge(s) => AttributeText::from(s),
+            Styles::Node(s) => AttributeText::from(s),
+            Styles::Graph(s) => AttributeText::from(s),
+        }
+    }
+}
+
+impl<'a> From<u32> for AttributeText<'a> {
+    fn from(v: u32) -> Self {
+        AttributeText::attr(v.to_string())
+    }
+}
+
+#[derive(Hash, Eq, PartialEq, PartialOrd, Ord, Debug, Clone)]
+pub enum AttributeType {
+    Graph,
+    Node,
+    Edge,
+}
+
+pub trait AttributeStatement<'a> {
+    fn get_attribute_statement_type(&self) -> &'static str;
+
+    fn get_attributes(&self) -> &IndexMap<String, AttributeText<'a>>;
+
+    fn dot_string(&self) -> String {
+        if self.get_attributes().is_empty() {
+            return String::from("");
+        }
+        let mut dot_string = format!("{} [", self.get_attribute_statement_type());
+        let attributes = &self.get_attributes();
+        let mut iter = attributes.iter();
+        let first = iter.next().unwrap();
+        dot_string.push_str(format!("{}={}", first.0, first.1.dot_string()).as_str());
+        for (key, value) in iter {
+            dot_string.push_str(", ");
+            dot_string.push_str(format!("{}={}", key, value.dot_string()).as_str());
+        }
+        dot_string.push_str("];");
+        dot_string.to_string()
+    }
+}
+
+pub trait GraphAttributes<'a> {
+    fn background(&mut self, background: String) -> &mut Self {
+        self.add_attribute("_background", AttributeText::attr(background))
+    }
+
+    /// The color used as the background for entire canvas.
+    fn background_color(&mut self, background_color: Color<'a>) -> &mut Self {
+        self.add_attribute("bgcolor", AttributeText::from(background_color))
+    }
+
+    // TODO: constrain
+    /// The color used as the background for entire canvas with a gradient fill.
+    /// A colon-separated list of weighted color values: WC(:WC)* where each WC has the form C(;F)?
+    /// with C a color value and the optional F a floating-point number, 0 ≤ F ≤ 1.
+    /// The sum of the floating-point numbers in a colorList must sum to at most 1.
+    fn background_colorlist(&mut self, background_colors: ColorList<'a>) -> &mut Self {
+        self.add_attribute("bgcolor", AttributeText::from(background_colors))
+    }
+
+    /// Type: rect which is "%f,%f,%f,%f"
+    /// The rectangle llx,lly,urx,ury gives the coordinates, in points, of the lower-left corner (llx,lly)
+    /// and the upper-right corner (urx,ury).
+    fn bounding_box(&mut self, bounding_box: String) -> &mut Self {
+        self.add_attribute("bb", AttributeText::quoted(bounding_box))
+    }
+
+    /// If true, the drawing is centered in the output canvas.
+    fn center(&mut self, center: bool) -> &mut Self {
+        self.add_attribute("center", AttributeText::from(center))
+    }
+
+    /// Specifies the character encoding used when interpreting string input as a text label.
+    fn charset(&mut self, charset: String) -> &mut Self {
+        self.add_attribute("charset", AttributeText::quoted(charset))
+    }
+
+    /// Classnames to attach to the node, edge, graph, or cluster’s SVG element.
+    /// Combine with stylesheet for styling SVG output using CSS classnames.
+    /// Multiple space-separated classes are supported.
+    fn class(&mut self, class: String) -> &mut Self {
+        Attributes::class(self.get_attributes_mut(), class);
+        self
+    }
+
+    /// Mode used for handling clusters.
+    /// If clusterrank=local, a subgraph whose name begins with cluster is given special treatment.
+    /// The subgraph is laid out separately, and then integrated as a unit into its parent graph,
+    ///  with a bounding rectangle drawn about it.
+    /// If the cluster has a label parameter, this label is displayed within the rectangle.
+    /// Note also that there can be clusters within clusters.
+    /// The modes clusterrank=global and clusterrank=none appear to be identical, both turning off the special cluster processing.
+    fn cluster_rank(&mut self, cluster_rank: ClusterMode) -> &mut Self {
+        self.add_attribute("clusterrank", AttributeText::from(cluster_rank))
+    }
+
+    /// This attribute specifies a color scheme namespace: the context for interpreting color names.
+    /// In particular, if a color value has form "xxx" or "//xxx", then the color xxx will be evaluated
+    /// according to the current color scheme. If no color scheme is set, the standard X11 naming is used.
+    /// For example, if colorscheme=bugn9, then color=7 is interpreted as color="/bugn9/7".
+    fn color_scheme(&mut self, color_scheme: String) -> &mut Self {
+        Attributes::color_scheme(self.get_attributes_mut(), color_scheme);
+        self
+    }
+
+    /// Comments are inserted into output. Device-dependent
+    fn comment(&mut self, comment: String) -> &mut Self {
+        Attributes::comment(self.get_attributes_mut(), comment);
+        self
+    }
+
+    fn compound(&mut self, compound: String) -> &mut Self {
+        self.add_attribute("compound", AttributeText::quoted(compound))
+    }
+
+    fn concentrate(&mut self, concentrate: String) -> &mut Self {
+        self.add_attribute("concentrate", AttributeText::quoted(concentrate))
+    }
+
+    /// Specifies the expected number of pixels per inch on a display device.
+    /// Also known as resolution
+    fn dpi(&mut self, dpi: f32) -> &mut Self {
+        self.add_attribute("dpi", AttributeText::from(dpi))
+    }
+
+    /// Color used to fill the background of a node or cluster assuming style=filled, or a filled arrowhead.
+    fn fill_color(&mut self, fill_color: Color<'a>) -> &mut Self {
+        Attributes::fill_color(self.get_attributes_mut(), fill_color);
+        self
+    }
+
+    /// Color used to fill the background, with a gradient, of a node or cluster assuming
+    /// style=filled, or a filled arrowhead.
+    fn fill_color_with_colorlist(&mut self, fill_colors: ColorList<'a>) -> &mut Self {
+        Attributes::fill_color_with_colorlist(self.get_attributes_mut(), fill_colors);
+        self
+    }
+
+    /// Color used to fill the background, with a gradient, of a node or cluster assuming
+    /// style=filled, or a filled arrowhead.
+    /// TODO: example
+    /// [crate::GraphAttributes::dpi]
+    fn fill_color_with_iter<I>(&mut self, fill_colors: I) -> &mut Self
+    where
+        I: IntoIterator,
+        I::Item: IntoWeightedColor<'a>,
+    {
+        Attributes::fill_color_with_iter(self.get_attributes_mut(), fill_colors);
+        self
+    }
+
+    /// Color used for text.
+    fn font_color(&mut self, font_color: Color<'a>) -> &mut Self {
+        Attributes::font_color(self.get_attributes_mut(), font_color);
+        self
+    }
+
+    /// Font used for text.
+    fn font_name(&mut self, font_name: String) -> &mut Self {
+        Attributes::font_name(self.get_attributes_mut(), font_name);
+        self
+    }
+
+    fn font_names(&mut self, font_names: String) -> &mut Self {
+        self.add_attribute("fontnames", AttributeText::quoted(font_names))
+    }
+
+    fn font_path(&mut self, font_path: String) -> &mut Self {
+        self.add_attribute("fontpath", AttributeText::quoted(font_path))
+    }
+
+    // TODO: constrain
+    /// Font size, in points, used for text.
+    /// default: 14.0, minimum: 1.0
+    fn font_size(&mut self, font_size: f32) -> &mut Self {
+        Attributes::font_size(self.get_attributes_mut(), font_size);
+        self
+    }
+
+    fn force_label(&mut self, force_label: bool) -> &mut Self {
+        self.add_attribute("forcelabel", AttributeText::from(force_label))
+    }
+
+    /// If a gradient fill is being used, this determines the angle of the fill.
+    fn gradient_angle(&mut self, gradient_angle: u32) -> &mut Self {
+        Attributes::gradient_angle(self.get_attributes_mut(), gradient_angle);
+        self
+    }
+
+    fn image_path(&mut self, image_path: String) -> &mut Self {
+        self.add_attribute("imagepath", AttributeText::escaped(image_path))
+    }
+
+    /// An escString or an HTML label.
+    fn label(&mut self, label: String) -> &mut Self {
+        Attributes::label(self.get_attributes_mut(), label);
+        self
+    }
+
+    /// If labeljust=r, the label is right-justified within bounding rectangle
+    /// If labeljust=l, left-justified
+    /// Else the label is centered.
+    fn label_justification(
+        &mut self,
+        label_justification: LabelJustification,
+    ) -> &mut Self {
+        self.add_attribute("labeljust", AttributeText::from(label_justification))
+    }
+
+    // Vertical placement of labels for nodes, root graphs and clusters.
+    // For graphs and clusters, only labelloc=t and labelloc=b are allowed, corresponding to
+    // placement at the top and bottom, respectively.
+    // By default, root graph labels go on the bottom and cluster labels go on the top.
+    // Note that a subgraph inherits attributes from its parent. Thus, if the root graph sets
+    // labelloc=b, the subgraph inherits this value.
+    // For nodes, this attribute is used only when the height of the node is larger than the height
+    // of its label.
+    // If labelloc=t, labelloc=c, labelloc=b, the label is aligned with the top, centered, or
+    // aligned with the bottom of the node, respectively.
+    // By default, the label is vertically centered.
+    fn label_location(&mut self, label_location: LabelLocation) -> &mut Self {
+        Attributes::label_location(self.get_attributes_mut(), label_location);
+        self
+    }
+
+    fn landscape(&mut self, landscape: bool) -> &mut Self {
+        self.add_attribute("landscape", AttributeText::from(landscape))
+    }
+
+    /// Specifies the separator characters used to split an attribute of type layerRange into a
+    /// list of ranges.
+    fn layer_list_sep(&mut self, layer_list_sep: String) -> &mut Self {
+        self.add_attribute("layerlistsep", AttributeText::attr(layer_list_sep))
+    }
+
+    /// Specifies a linearly ordered list of layer names attached to the graph
+    /// The graph is then output in separate layers.
+    /// Only those components belonging to the current output layer appear.
+    fn layers(&mut self, layers: String) -> &mut Self {
+        Attributes::layer(self.get_attributes_mut(), layers);
+        self
+    }
+
+    /// Selects a list of layers to be emitted.
+    fn layer_select(&mut self, layer_select: String) -> &mut Self {
+        self.add_attribute("layerselect", AttributeText::attr(layer_select))
+    }
+
+    /// Specifies the separator characters used to split the layers attribute into a list of layer names.
+    /// default: ":\t "
+    fn layer_sep(&mut self, layer_sep: String) -> &mut Self {
+        self.add_attribute("layersep", AttributeText::attr(layer_sep))
+    }
+
+    /// Height of graph or cluster label, in inches.
+    fn lheight(&mut self, lheight: f32) -> &mut Self {
+        self.add_attribute("lheight", AttributeText::from(lheight))
+    }
+
+    /// Label position
+    /// The position indicates the center of the label.
+    fn label_position(&mut self, lp: Point) -> &mut Self {
+        Attributes::label_position(self.get_attributes_mut(), lp);
+        self
+    }
+
+    /// Width of graph or cluster label, in inches.
+    fn lwidth(&mut self, lwidth: f32) -> &mut Self {
+        self.add_attribute("lwidth", AttributeText::from(lwidth))
+    }
+
+    /// Sets x and y margins of canvas, in inches.
+    /// Both margins are set equal to the given value.
+    /// See [`crate::GraphAttributes::margin_point`]
+    fn margin(&mut self, margin: f32) -> &mut Self {
+        self.margin_point(Point::new_2d(margin, margin))
+    }
+
+    /// Sets x and y margins of canvas, in inches.
+    /// Note that the margin is not part of the drawing but just empty space left around the drawing.
+    /// The margin basically corresponds to a translation of drawing, as would be necessary to
+    /// center a drawing on a page. Nothing is actually drawn in the margin.
+    /// To actually extend the background of a drawing, see the pad attribute.
+    /// Whilst it is possible to create a Point value with either a third co-ordinate
+    /// or a forced position, these are ignored for printing.
+    /// By default, the value is 0.11,0.055.
+    fn margin_point(&mut self, margin: Point) -> &mut Self {
+        Attributes::margin(self.get_attributes_mut(), margin);
+        self
+    }
+
+    /// Multiplicative scale factor used to alter the MinQuit (default = 8) and
+    /// MaxIter (default = 24) parameters used during crossing minimization.
+    /// These correspond to the number of tries without improvement before quitting and the
+    /// maximum number of iterations in each pass.
+    fn mclimit(&mut self, mclimit: f32) -> &mut Self {
+        self.add_attribute("mclimit", AttributeText::from(mclimit))
+    }
+
+    /// Specifies the minimum separation between all nodes.
+    fn mindist(&mut self, mindist: u32) -> &mut Self {
+        self.add_attribute("mindist", AttributeText::from(mindist))
+    }
+
+    /// Whether to use a single global ranking, ignoring clusters.
+    /// The original ranking algorithm in dot is recursive on clusters.
+    /// This can produce fewer ranks and a more compact layout, but sometimes at the cost of a
+    /// head node being place on a higher rank than the tail node.
+    /// It also assumes that a node is not constrained in separate, incompatible subgraphs.
+    /// For example, a node cannot be in a cluster and also be constrained by rank=same with
+    /// a node not in the cluster.
+    /// This allows nodes to be subject to multiple constraints.
+    /// Rank constraints will usually take precedence over edge constraints.
+    fn newrank(&mut self, newrank: bool) -> &mut Self {
+        self.add_attribute("newrank", AttributeText::from(newrank))
+    }
+
+    // TODO: add constraint
+    /// specifies the minimum space between two adjacent nodes in the same rank, in inches.
+    /// default: 0.25, minimum: 0.02
+    fn nodesep(&mut self, nodesep: f32) -> &mut Self {
+        self.add_attribute("nodesep", AttributeText::from(nodesep))
+    }
+
+    /// By default, the justification of multi-line labels is done within the largest context that makes sense.
+    /// Thus, in the label of a polygonal node, a left-justified line will align with the left side
+    /// of the node (shifted by the prescribed margin).
+    /// In record nodes, left-justified line will line up with the left side of the enclosing column
+    /// of fields.
+    /// If nojustify=true, multi-line labels will be justified in the context of itself.
+    /// For example, if nojustify is set, the first label line is long, and the second is shorter
+    /// and left-justified,
+    /// the second will align with the left-most character in the first line, regardless of how
+    /// large the node might be.
+    fn no_justify(&mut self, no_justify: bool) -> &mut Self {
+        Attributes::no_justify(self.get_attributes_mut(), no_justify);
+        self
+    }
+
+    /// Sets number of iterations in network simplex applications.
+    /// nslimit is used in computing node x coordinates.
+    /// If defined, # iterations = nslimit * # nodes; otherwise, # iterations = MAXINT.
+    fn nslimit(&mut self, nslimit: f32) -> &mut Self {
+        self.add_attribute("nslimit", AttributeText::from(nslimit))
+    }
+
+    /// If ordering="out", then the outedges of a node, that is, edges with the node as its tail
+    /// node, must appear left-to-right in the same order in which they are defined in the input.
+    ///
+    /// If ordering="in", then the inedges of a node must appear left-to-right in the same order in
+    /// which they are defined in the input.
+    ///
+    /// If defined as a graph or subgraph attribute, the value is applied to all nodes in the graph
+    /// or subgraph.
+    ///
+    /// Note that the graph attribute takes precedence over the node attribute.
+    fn ordering(&mut self, ordering: Ordering) -> &mut Self {
+        Attributes::ordering(self.get_attributes_mut(), ordering);
+        self
+    }
+
+    // TODO: constrain to 0 - 360. Docs say min is 360 which should be max right?
+    /// When used on nodes: Angle, in degrees, to rotate polygon node shapes.
+    /// For any number of polygon sides, 0 degrees rotation results in a flat base.
+    /// When used on graphs: If "[lL]*", sets graph orientation to landscape.
+    /// Used only if rotate is not defined.
+    /// Default: 0.0 and minimum: 360.0
+    fn orientation(&mut self, orientation: f32) -> &mut Self {
+        Attributes::orientation(self.get_attributes_mut(), orientation);
+        self
+    }
+
+    /// Specify order in which nodes and edges are drawn.
+    /// default: breadthfirst
+    fn output_order(&mut self, output_order: OutputMode) -> &mut Self {
+        self.add_attribute("outputorder", AttributeText::from(output_order))
+    }
+
+    /// Whether each connected component of the graph should be laid out separately, and then the
+    /// graphs packed together.
+    /// If false, the entire graph is laid out together.
+    /// The granularity and method of packing is influenced by the packmode attribute.
+    fn pack(&mut self, pack: bool) -> &mut Self {
+        self.add_attribute("pack", AttributeText::from(pack))
+    }
+
+    // TODO: constrain to non-negative integer.
+    /// Whether each connected component of the graph should be laid out separately, and then
+    /// the graphs packed together.
+    /// This is used as the size, in points,of a margin around each part; otherwise, a default
+    /// margin of 8 is used.
+    /// pack is treated as true if the value of pack iso a non-negative integer.
+    fn pack_int(&mut self, pack: u32) -> &mut Self {
+        self.add_attribute("pack", AttributeText::from(pack))
+    }
+
+    /// This indicates how connected components should be packed (cf. packMode).
+    /// Note that defining packmode will automatically turn on packing as though one had set pack=true.
+    fn pack_mode(&mut self, pack_mode: PackMode) -> &mut Self {
+        self.add_attribute("packmode", AttributeText::from(pack_mode))
+    }
+
+    /// Specifies how much, in inches, to extend the drawing area around the minimal area needed
+    /// to draw the graph.
+    /// Both the x and y pad values are set equal to the given value.
+    /// See [`crate::GraphAttributes::pad_point`]
+    fn pad(&mut self, pad: f32) -> &mut Self {
+        self.pad_point(Point::new_2d(pad, pad))
+    }
+
+    /// Specifies how much, in inches, to extend the drawing area around the minimal area needed to
+    /// draw the graph.
+    /// This area is part of the drawing and will be filled with the background color, if appropriate.
+    /// default: 0.0555
+    fn pad_point(&mut self, pad: Point) -> &mut Self {
+        self.add_attribute("pad", AttributeText::from(pad))
+    }
+
+    /// Width and height of output pages, in inches.
+    /// Value given is used for both the width and height.
+    fn page(&mut self, page: f32) -> &mut Self {
+        self.add_attribute("page", AttributeText::from(page))
+    }
+
+    /// Width and height of output pages, in inches.
+    fn page_point(&mut self, page: Point) -> &mut Self {
+        self.add_attribute("page", AttributeText::from(page))
+    }
+
+    /// The order in which pages are emitted.
+    /// Used only if page is set and applicable.
+    /// Limited to one of the 8 row or column major orders.
+    fn page_dir(&mut self, page_dir: PageDirection) -> &mut Self {
+        self.add_attribute("pagedir", AttributeText::from(page_dir))
+    }
+
+    // TODO: constrain
+    /// If quantum > 0.0, node label dimensions will be rounded to integral multiples of the quantum.
+    /// default: 0.0, minimum: 0.0
+    fn quantum(&mut self, quantum: f32) -> &mut Self {
+        self.add_attribute("quantum", AttributeText::from(quantum))
+    }
+
+    /// Sets direction of graph layout.
+    /// For example, if rankdir="LR", and barring cycles, an edge T -> H; will go from left to right.
+    /// By default, graphs are laid out from top to bottom.
+    /// This attribute also has a side-effect in determining how record nodes are interpreted.
+    /// See record shapes.
+    fn rank_dir(&mut self, rank_dir: RankDir) -> &mut Self {
+        self.add_attribute("rankdir", AttributeText::from(rank_dir))
+    }
+
+    /// sets the desired rank separation, in inches.
+    /// This is the minimum vertical distance between the bottom of the nodes in one rank
+    /// and the tops of nodes in the next. If the value contains equally,
+    /// the centers of all ranks are spaced equally apart.
+    /// Note that both settings are possible, e.g., ranksep="1.2 equally".
+    fn rank_sep(&mut self, rank_sep: String) -> &mut Self {
+        self.add_attribute("ranksep", AttributeText::attr(rank_sep))
+    }
+
+    /// Sets the aspect ratio (drawing height/drawing width) for the drawing.
+    /// Note that this is adjusted before the size attribute constraints are enforced.
+    fn ratio(&mut self, ratio: Ratio) -> &mut Self {
+        self.add_attribute("ratio", AttributeText::from(ratio))
+    }
+
+    /// If true and there are multiple clusters, run crossing minimization a second time.
+    fn remincross(&mut self, remincross: bool) -> &mut Self {
+        self.add_attribute("remincross", AttributeText::from(remincross))
+    }
+
+    /// If rotate=90, sets drawing orientation to landscape.
+    fn rotate(&mut self, rotate: u32) -> &mut Self {
+        self.add_attribute("rotate", AttributeText::from(rotate))
+    }
+
+    // TODO: constrain
+    /// Print guide boxes in PostScript at the beginning of routesplines if showboxes=1, or at
+    /// the end if showboxes=2.
+    /// (Debugging, TB mode only!)
+    /// default: 0, minimum: 0
+    fn show_boxes(&mut self, show_boxes: u32) -> &mut Self {
+        Attributes::show_boxes(self.get_attributes_mut(), show_boxes);
+        self
+    }
+
+    /// Maximum width and height of drawing, in inches.
+    /// Value used for both the width and the height.
+    /// If defined and the drawing is larger than the given size, the drawing
+    /// is uniformly scaled down so that it fits within the given size.
+    /// If desired_min is true, and both both dimensions of the drawing
+    /// are less than size, the drawing is scaled up uniformly until at
+    /// least one dimension equals its dimension in size.
+    /// See [`crate::GraphAttributes::size_point`]
+    fn size(&mut self, size: u32, desired_min: bool) -> &mut Self {
+        self.size_point(Point {
+            x: size as f32,
+            y: size as f32,
+            z: None,
+            force_pos: desired_min,
+        })
+    }
+
+    /// Maximum width and height of drawing, in inches.
+    /// If defined and the drawing is larger than the given size, the drawing
+    /// is uniformly scaled down so that it fits within the given size.
+    /// If desired_min is true, and both both dimensions of the drawing
+    /// are less than size, the drawing is scaled up uniformly until at
+    /// least one dimension equals its dimension in size.
+    fn size_point(&mut self, size: Point) -> &mut Self {
+        self.add_attribute("size", AttributeText::from(size))
+    }
+
+    /// If packmode indicates an array packing, sortv specifies an insertion order
+    /// among the components, with smaller values inserted first.
+    /// default: 0, minimum: 0
+    fn sortv(&mut self, sortv: u32) -> &mut Self {
+        Attributes::sortv(self.get_attributes_mut(), sortv);
+        self
+    }
+
+    /// Controls how, and if, edges are represented.
+    fn splines(&mut self, splines: Splines) -> &mut Self {
+        self.add_attribute("splines", AttributeText::from(splines))
+    }
+
+    /// Set style information for components of the graph.
+    fn style(&mut self, style: GraphStyle) -> &mut Self {
+        Attributes::style(self.get_attributes_mut(), Styles::Graph(style));
+        self
+    }
+
+    /// A URL or pathname specifying an XML style sheet, used in SVG output.
+    /// Combine with class to style elements using CSS selectors.
+    fn stylesheet(&mut self, stylesheet: String) -> &mut Self {
+        self.add_attribute("stylesheet", AttributeText::attr(stylesheet))
+    }
+
+    /// If the object has a URL, this attribute determines which window of the browser is used for the URL.
+    fn target(&mut self, target: String) -> &mut Self {
+        Attributes::target(self.get_attributes_mut(), target);
+        self
+    }
+
+    /// Whether internal bitmap rendering relies on a truecolor color model or uses a color palette.
+    /// If truecolor is unset, truecolor is not used unless there is a shapefile property
+    /// for some node in the graph.
+    /// The output model will use the input model when possible.
+    fn true_color(&mut self, true_color: bool) -> &mut Self {
+        self.add_attribute("truecolor", AttributeText::from(true_color))
+    }
+
+    /// Hyperlinks incorporated into device-dependent output.
+    fn url(&mut self, url: String) -> &mut Self {
+        Attributes::url(self.get_attributes_mut(), url);
+        self
+    }
+
+    // TODO: add a ViewPort Struct?
+    /// Clipping window on final drawing.
+    /// viewport supersedes any size attribute.
+    /// The width and height of the viewport specify precisely the final size of the output.
+    /// The viewPort W,H,Z,x,y or W,H,Z,N specifies a viewport for the final image.
+    /// The pair (W,H) gives the dimensions (width and height) of the final image, in points.
+    /// The optional Z is the zoom factor, i.e., the image in the original layout will be
+    /// W/Z by H/Z points in size. By default, Z is 1.
+    /// The optional last part is either a pair (x,y) giving a position in the original layout
+    /// of the graph,
+    /// in points, of the center of the viewport, or the name N of a node whose center should used
+    /// as the focus.
+    fn viewport(&mut self, viewport: String) -> &mut Self {
+        self.add_attribute("viewport", AttributeText::attr(viewport))
+    }
+
+    /// Add an attribute to the node.
+    fn add_attribute<S: Into<String>>(
+        &mut self,
+        key: S,
+        value: AttributeText<'a>,
+    ) -> &mut Self;
+
+    /// Add multiple attributes to the node.
+    fn add_attributes(
+        &'a mut self,
+        attributes: HashMap<String, AttributeText<'a>>,
+    ) -> &mut Self;
+
+    fn get_attributes_mut(&mut self) -> &mut IndexMap<String, AttributeText<'a>>;
+}
+
+impl<'a> GraphAttributes<'a> for GraphAttributeStatementBuilder<'a> {
+    fn add_attribute<S: Into<String>>(
+        &mut self,
+        key: S,
+        value: AttributeText<'a>,
+    ) -> &mut Self {
+        self.attributes.insert(key.into(), value);
+        self
+    }
+
+    /// Add multiple attributes to the node.
+    fn add_attributes(
+        &'a mut self,
+        attributes: HashMap<String, AttributeText<'a>>,
+    ) -> &mut Self {
+        self.attributes.extend(attributes);
+        self
+    }
+
+    fn get_attributes_mut(&mut self) -> &mut IndexMap<String, AttributeText<'a>> {
+        &mut self.attributes
+    }
+}
+
+// I'm not a huge fan of needing this builder but having a hard time getting around &mut without it
+pub struct GraphAttributeStatementBuilder<'a> {
+    pub attributes: IndexMap<String, AttributeText<'a>>,
+}
+
+impl<'a> GraphAttributeStatementBuilder<'a> {
+    pub fn new() -> Self {
+        Self {
+            attributes: IndexMap::new(),
+        }
+    }
+
+    pub fn build(&self) -> GraphAttributeStatement<'a> {
+        GraphAttributeStatement {
+            attributes: self.attributes.clone(),
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct GraphAttributeStatement<'a> {
+    pub attributes: IndexMap<String, AttributeText<'a>>,
+}
+
+impl<'a> GraphAttributeStatement<'a> {
+    pub fn new() -> Self {
+        Self {
+            attributes: IndexMap::new(),
+        }
+    }
+
+    pub fn add_attribute<S: Into<String>>(
+        &mut self,
+        key: S,
+        value: AttributeText<'a>,
+    ) -> &mut Self {
+        self.attributes.insert(key.into(), value);
+        self
+    }
+}
+
+impl<'a> AttributeStatement<'a> for GraphAttributeStatement<'a> {
+    fn get_attribute_statement_type(&self) -> &'static str {
+        "graph"
+    }
+
+    fn get_attributes(&self) -> &IndexMap<String, AttributeText<'a>> {
+        &self.attributes
+    }
+}
+
+pub(crate) struct Attributes;
+impl Attributes {
+    pub fn class(attributes: &mut IndexMap<String, AttributeText>, class: String) {
+        Self::add_attribute(attributes, "class", AttributeText::quoted(class))
+    }
+
+    pub fn color<'a>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        color: Color<'a>,
+    ) {
+        Self::add_attribute(attributes, "color", AttributeText::from(color))
+    }
+
+    pub fn color_with_colorlist<'a>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        color: ColorList<'a>,
+    ) {
+        Self::add_attribute(attributes, "color", AttributeText::from(color))
+    }
+
+    pub fn color_scheme(
+        attributes: &mut IndexMap<String, AttributeText>,
+        color_scheme: String,
+    ) {
+        Self::add_attribute(
+            attributes,
+            "colorscheme",
+            AttributeText::quoted(color_scheme),
+        )
+    }
+
+    pub fn comment(attributes: &mut IndexMap<String, AttributeText>, comment: String) {
+        Self::add_attribute(attributes, "comment", AttributeText::quoted(comment))
+    }
+
+    pub fn fill_color<'a>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        fill_color: Color<'a>,
+    ) {
+        Self::add_attribute(attributes, "fillcolor", AttributeText::from(fill_color))
+    }
+
+    pub fn fill_color_with_colorlist<'a>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        fill_colors: ColorList<'a>,
+    ) {
+        Self::add_attribute(attributes, "fillcolor", AttributeText::from(fill_colors))
+    }
+
+    pub fn fill_color_with_iter<'a, I>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        fill_colors: I,
+    ) where
+        I: IntoIterator,
+        I::Item: IntoWeightedColor<'a>,
+    {
+        let colors: Vec<WeightedColor> = fill_colors
+            .into_iter()
+            .map(|e| e.into_weighted_color())
+            .collect();
+
+        let color_list = ColorList { colors };
+
+        Self::add_attribute(attributes, "fillcolor", AttributeText::from(color_list))
+    }
+
+    pub fn font_color<'a>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        font_color: Color<'a>,
+    ) {
+        Self::add_attribute(attributes, "fontcolor", AttributeText::from(font_color))
+    }
+
+    pub fn font_name(
+        attributes: &mut IndexMap<String, AttributeText>,
+        font_name: String,
+    ) {
+        Self::add_attribute(attributes, "fontname", AttributeText::quoted(font_name))
+    }
+
+    pub fn font_size(attributes: &mut IndexMap<String, AttributeText>, font_size: f32) {
+        Self::add_attribute(attributes, "fontsize", AttributeText::from(font_size))
+    }
+
+    pub fn gradient_angle(
+        attributes: &mut IndexMap<String, AttributeText>,
+        gradient_angle: u32,
+    ) {
+        Self::add_attribute(
+            attributes,
+            "gradientangle",
+            AttributeText::from(gradient_angle),
+        )
+    }
+
+    pub fn label(attributes: &mut IndexMap<String, AttributeText>, text: String) {
+        Self::add_attribute(attributes, "label", AttributeText::quoted(text));
+    }
+
+    pub fn label_location(
+        attributes: &mut IndexMap<String, AttributeText>,
+        label_location: LabelLocation,
+    ) {
+        Self::add_attribute(attributes, "labelloc", AttributeText::from(label_location))
+    }
+
+    // TODO: layer struct
+    pub fn layer(attributes: &mut IndexMap<String, AttributeText>, layer: String) {
+        Self::add_attribute(attributes, "layer", AttributeText::attr(layer))
+    }
+
+    pub fn label_position(attributes: &mut IndexMap<String, AttributeText>, lp: Point) {
+        Self::add_attribute(attributes, "lp", AttributeText::from(lp))
+    }
+
+    pub fn margin(attributes: &mut IndexMap<String, AttributeText>, margin: Point) {
+        Self::add_attribute(attributes, "margin", AttributeText::from(margin))
+    }
+
+    pub fn no_justify(
+        attributes: &mut IndexMap<String, AttributeText>,
+        no_justify: bool,
+    ) {
+        Self::add_attribute(attributes, "nojustify", AttributeText::from(no_justify))
+    }
+
+    pub fn ordering(
+        attributes: &mut IndexMap<String, AttributeText>,
+        ordering: Ordering,
+    ) {
+        Self::add_attribute(attributes, "ordering", AttributeText::from(ordering))
+    }
+
+    pub fn orientation(
+        attributes: &mut IndexMap<String, AttributeText>,
+        orientation: f32,
+    ) {
+        Self::add_attribute(attributes, "orientation", AttributeText::from(orientation))
+    }
+
+    pub fn pen_width(attributes: &mut IndexMap<String, AttributeText>, pen_width: f32) {
+        Self::add_attribute(attributes, "penwidth", AttributeText::from(pen_width))
+    }
+
+    // TODO: splinetype
+    pub fn pos(attributes: &mut IndexMap<String, AttributeText>, pos: Point) {
+        Self::add_attribute(attributes, "pos", AttributeText::from(pos))
+    }
+
+    pub fn show_boxes(
+        attributes: &mut IndexMap<String, AttributeText>,
+        show_boxes: u32,
+    ) {
+        Self::add_attribute(attributes, "showboxes", AttributeText::from(show_boxes))
+    }
+
+    pub fn sortv(attributes: &mut IndexMap<String, AttributeText>, sortv: u32) {
+        Self::add_attribute(attributes, "sortv", AttributeText::from(sortv))
+    }
+
+    pub fn style(attributes: &mut IndexMap<String, AttributeText>, style: Styles) {
+        Self::add_attribute(attributes, "style", AttributeText::from(style))
+    }
+
+    pub fn target(attributes: &mut IndexMap<String, AttributeText>, target: String) {
+        Self::add_attribute(attributes, "target", AttributeText::escaped(target))
+    }
+
+    pub fn tooltip(attributes: &mut IndexMap<String, AttributeText>, tooltip: String) {
+        Self::add_attribute(attributes, "tooltip", AttributeText::escaped(tooltip))
+    }
+
+    pub fn url(attributes: &mut IndexMap<String, AttributeText>, url: String) {
+        Self::add_attribute(attributes, "url", AttributeText::escaped(url))
+    }
+
+    pub fn xlabel(attributes: &mut IndexMap<String, AttributeText>, width: String) {
+        Self::add_attribute(attributes, "xlabel", AttributeText::escaped(width))
+    }
+
+    pub fn xlp(attributes: &mut IndexMap<String, AttributeText>, xlp: Point) {
+        Self::add_attribute(attributes, "xlp", AttributeText::from(xlp))
+    }
+
+    pub fn add_attribute<'a, S: Into<String>>(
+        attributes: &mut IndexMap<String, AttributeText<'a>>,
+        key: S,
+        value: AttributeText<'a>,
+    ) {
+        attributes.insert(key.into(), value);
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::{
+        AttributeStatement, Color, GraphAttributeStatementBuilder, GraphAttributes,
+    };
+
+    #[test]
+    fn graph_attribute_colorlist_vec_dot_string() {
+        let graph_attributes = GraphAttributeStatementBuilder::new()
+            .fill_color_with_iter(&[
+                (Color::Named("yellow"), Some(0.3)),
+                (Color::Named("blue"), None),
+            ])
+            .build();
+
+        assert_eq!(
+            "graph [fillcolor=\"yellow;0.3:blue\"];",
+            graph_attributes.dot_string()
+        );
+    }
+}
diff --git a/src/attributes/ordering.rs b/src/attributes/ordering.rs
new file mode 100644
index 0000000..1cd13b6
--- /dev/null
+++ b/src/attributes/ordering.rs
@@ -0,0 +1,16 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum Ordering {
+    In,
+    Out,
+}
+
+impl<'a> DotString<'a> for Ordering {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Ordering::In => "in".into(),
+            Ordering::Out => "out".into(),
+        }
+    }
+}
diff --git a/src/attributes/output_mode.rs b/src/attributes/output_mode.rs
new file mode 100644
index 0000000..5a6ab45
--- /dev/null
+++ b/src/attributes/output_mode.rs
@@ -0,0 +1,29 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// These specify the order in which nodes and edges are drawn in concrete output.
+///
+/// The default "breadthfirst" is the simplest, but when the graph layout does not avoid edge-node
+/// overlap, this mode will sometimes have edges drawn over nodes and sometimes on top of nodes.
+///
+/// If the mode "nodesfirst" is chosen, all nodes are drawn first, followed by the edges.
+/// This guarantees an edge-node overlap will not be mistaken for an edge ending at a node.
+///
+/// On the other hand, usually for aesthetic reasons, it may be desirable that all edges appear
+/// beneath nodes, even if the resulting drawing is ambiguous.
+/// This can be achieved by choosing "edgesfirst".
+pub enum OutputMode {
+    BreadthFirst,
+    NodesFirst,
+    EdgesFirst,
+}
+
+impl<'a> DotString<'a> for OutputMode {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            OutputMode::BreadthFirst => "breadthfirst".into(),
+            OutputMode::NodesFirst => "nodesfirst".into(),
+            OutputMode::EdgesFirst => "edgesfirst".into(),
+        }
+    }
+}
diff --git a/src/attributes/pack_mode.rs b/src/attributes/pack_mode.rs
new file mode 100644
index 0000000..3fb086e
--- /dev/null
+++ b/src/attributes/pack_mode.rs
@@ -0,0 +1,30 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// The modes "node", "clust" or "graph" specify that the components should be packed together
+/// tightly, using the specified granularity.
+pub enum PackMode {
+    /// causes packing at the node and edge level, with no overlapping of these objects.
+    /// This produces a layout with the least area, but it also allows interleaving,
+    /// where a node of one component may lie between two nodes in another component.
+    Node,
+
+    /// guarantees that top-level clusters are kept intact.
+    /// What effect a value has also depends on the layout algorithm.
+    Cluster,
+
+    /// does a packing using the bounding box of the component.
+    /// Thus, there will be a rectangular region around a component free of elements of any other component.
+    Graph,
+    // TODO: array - "array(_flags)?(%d)?"
+}
+
+impl<'a> DotString<'a> for PackMode {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            PackMode::Node => "node".into(),
+            PackMode::Cluster => "clust".into(),
+            PackMode::Graph => "graph".into(),
+        }
+    }
+}
diff --git a/src/attributes/page_direction.rs b/src/attributes/page_direction.rs
new file mode 100644
index 0000000..df501ba
--- /dev/null
+++ b/src/attributes/page_direction.rs
@@ -0,0 +1,33 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// These specify the 8 row or column major orders for traversing a rectangular array,
+/// the first character corresponding to the major order and the second to the minor order.
+/// Thus, for “BL”, the major order is from bottom to top, and the minor order is from left to right.
+/// This means the bottom row is traversed first, from left to right, then the next row up,
+/// from left to right, and so on, until the topmost row is traversed
+pub enum PageDirection {
+    BottomLeft,
+    BottomRight,
+    TopLeft,
+    TopRight,
+    RightBottom,
+    RightTop,
+    LeftBottom,
+    LeftTop,
+}
+
+impl<'a> DotString<'a> for PageDirection {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            PageDirection::BottomLeft => "BL".into(),
+            PageDirection::BottomRight => "BR".into(),
+            PageDirection::TopLeft => "TL".into(),
+            PageDirection::TopRight => "TR".into(),
+            PageDirection::RightBottom => "RB".into(),
+            PageDirection::RightTop => "RT".into(),
+            PageDirection::LeftBottom => "LB".into(),
+            PageDirection::LeftTop => "LT".into(),
+        }
+    }
+}
diff --git a/src/attributes/point.rs b/src/attributes/point.rs
new file mode 100644
index 0000000..819044e
--- /dev/null
+++ b/src/attributes/point.rs
@@ -0,0 +1,55 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub struct Point {
+    pub x: f32,
+    pub y: f32,
+    pub z: Option<f32>,
+
+    /// specify that the node position should not change.
+    pub force_pos: bool,
+}
+
+impl Point {
+    pub fn new_2d(x: f32, y: f32) -> Self {
+        Self::new(x, y, None, false)
+    }
+
+    pub fn new_3d(x: f32, y: f32, z: f32) -> Self {
+        Self::new(x, y, Some(z), false)
+    }
+
+    pub fn new(x: f32, y: f32, z: Option<f32>, force_pos: bool) -> Self {
+        Self { x, y, z, force_pos }
+    }
+}
+
+impl<'a> DotString<'a> for Point {
+    fn dot_string(&self) -> Cow<'a, str> {
+        let mut slice = format!("{:.1},{:.1}", self.x, self.y);
+        if self.z.is_some() {
+            slice.push_str(format!(",{:.1}", self.z.unwrap()).as_str());
+        }
+        if self.force_pos {
+            slice.push_str("!")
+        }
+        slice.into()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::Point;
+    use crate::DotString;
+
+    #[test]
+    fn dot_string() {
+        assert_eq!("1.0,2.0", Point::new_2d(1.0, 2.0).dot_string());
+        assert_eq!("1.0,2.0,0.0", Point::new_3d(1.0, 2.0, 0.0).dot_string());
+        assert_eq!("1.0,2.0!", Point::new(1.0, 2.0, None, true).dot_string());
+        assert_eq!(
+            "1.0,2.0,0.0!",
+            Point::new(1.0, 2.0, Some(0.0), true).dot_string()
+        );
+    }
+}
diff --git a/src/attributes/port_position.rs b/src/attributes/port_position.rs
new file mode 100644
index 0000000..a492b14
--- /dev/null
+++ b/src/attributes/port_position.rs
@@ -0,0 +1,66 @@
+use crate::attributes::compass_point::CompassPoint;
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// Modifier indicating where on a node an edge should be aimed.
+/// If Port is used, the corresponding node must either have record shape with one of its
+/// fields having the given portname, or have an HTML-like label, one of whose components has a
+/// PORT attribute set to portname.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub enum PortPosition {
+    Port {
+        port_name: String,
+        compass_point: Option<CompassPoint>,
+    },
+    Compass(CompassPoint),
+}
+
+// TODO: AsRef vs this?
+// See https://github.com/Peternator7/strum/blob/96ee0a9a307ec7d1a39809fb59037bd4e11557cc/strum/src/lib.rs
+impl<'a> DotString<'a> for PortPosition {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            PortPosition::Port {
+                port_name,
+                compass_point,
+            } => {
+                let mut dot_string = port_name.to_owned();
+                if let Some(compass_point) = compass_point {
+                    dot_string
+                        .push_str(format!(":{}", compass_point.dot_string()).as_str());
+                }
+                dot_string.into()
+            }
+            PortPosition::Compass(p) => p.dot_string().into(),
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::{PortPosition, CompassPoint};
+    use crate::DotString;
+
+    #[test]
+    fn port_dot_string() {
+        assert_eq!(
+            "port_0",
+            PortPosition::Port {
+                port_name: "port_0".to_string(),
+                compass_point: None
+            }.dot_string()
+        );
+        assert_eq!(
+            "port_0:ne",
+            PortPosition::Port {
+                port_name: "port_0".to_string(),
+                compass_point: Some(CompassPoint::NE)
+            }.dot_string()
+        );
+    }
+
+    #[test]
+    fn compass_dot_string() {
+        assert_eq!("ne", PortPosition::Compass(CompassPoint::NE).dot_string());
+    }
+}
\ No newline at end of file
diff --git a/src/attributes/rankdir.rs b/src/attributes/rankdir.rs
new file mode 100644
index 0000000..58fdeff
--- /dev/null
+++ b/src/attributes/rankdir.rs
@@ -0,0 +1,22 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// Corresponding to directed graphs drawn from top to bottom, from left to right,
+/// from bottom to top, and from right to left, respectively.
+pub enum RankDir {
+    TopBottom,
+    LeftRight,
+    BottomTop,
+    RightLeft,
+}
+
+impl<'a> DotString<'a> for RankDir {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            RankDir::TopBottom => "TB".into(),
+            RankDir::LeftRight => "LR".into(),
+            RankDir::BottomTop => "BT".into(),
+            RankDir::RightLeft => "RL".into(),
+        }
+    }
+}
diff --git a/src/attributes/ratio.rs b/src/attributes/ratio.rs
new file mode 100644
index 0000000..a8fbad8
--- /dev/null
+++ b/src/attributes/ratio.rs
@@ -0,0 +1,22 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum Ratio {
+    Aspect(f32),
+    Fill,
+    Compress,
+    Expand,
+    Auto,
+}
+
+impl<'a> DotString<'a> for Ratio {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Ratio::Aspect(aspect) => aspect.to_string().into(),
+            Ratio::Fill => "fill".into(),
+            Ratio::Compress => "compress".into(),
+            Ratio::Expand => "expand".into(),
+            Ratio::Auto => "auto".into(),
+        }
+    }
+}
diff --git a/src/attributes/rectangle.rs b/src/attributes/rectangle.rs
new file mode 100644
index 0000000..9b36ee2
--- /dev/null
+++ b/src/attributes/rectangle.rs
@@ -0,0 +1,33 @@
+use crate::attributes::point::Point;
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub struct Rectangle {
+    lower_left: Point,
+    upper_right: Point,
+}
+
+impl<'a> DotString<'a> for Rectangle {
+    fn dot_string(&self) -> Cow<'a, str> {
+        format!(
+            "{:.1},{:.1},{:.1},{:.1}",
+            self.lower_left.x, self.lower_left.y, self.upper_right.x, self.upper_right.y
+        )
+        .into()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::{Rectangle, Point};
+    use crate::DotString;
+
+    #[test]
+    fn dot_string() {
+        assert_eq!("0.0,0.0,1.0,1.0", Rectangle {
+            lower_left: Point::new_2d(0.0, 0.0),
+            upper_right: Point::new_2d(1.0, 1.0)
+        }.dot_string());
+    }
+
+}
\ No newline at end of file
diff --git a/src/attributes/shape.rs b/src/attributes/shape.rs
new file mode 100644
index 0000000..be37ccc
--- /dev/null
+++ b/src/attributes/shape.rs
@@ -0,0 +1,132 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum Shape {
+    Box,
+    Polygon,
+    Ellipse,
+    Oval,
+    Circle,
+    Point,
+    Egg,
+    Triangle,
+    Plaintext,
+    Plain,
+    Diamond,
+    Trapezium,
+    Parallelogram,
+    House,
+    Pentagon,
+    Hexagon,
+    Septagon,
+    Octagon,
+    DoubleCircle,
+    DoubleOctagon,
+    TripleOctagon,
+    Invtriangle,
+    Invtrapezium,
+    Invhouse,
+    Mdiamond,
+    Msquare,
+    Mcircle,
+    Record,
+    Rect,
+    Rectangle,
+    Square,
+    Star,
+    None,
+    Underline,
+    Cylinder,
+    Note,
+    Tab,
+    Folder,
+    Box3D,
+    Component,
+    Promoter,
+    Cds,
+    Terminator,
+    Utr,
+    Primersite,
+    Restrictionsite,
+    FivePoverHang,
+    ThreePoverHang,
+    NoverHang,
+    Assemply,
+    Signature,
+    Insulator,
+    Ribosite,
+    Rnastab,
+    Proteasesite,
+    Proteinstab,
+    Rpromotor,
+    Rarrow,
+    Larrow,
+    Lpromotor,
+}
+
+impl<'a> DotString<'a> for Shape {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Shape::Box => "box".into(),
+            Shape::Polygon => "polygon".into(),
+            Shape::Ellipse => "ellipse".into(),
+            Shape::Oval => "oval".into(),
+            Shape::Circle => "circle".into(),
+            Shape::Point => "point".into(),
+            Shape::Egg => "egg".into(),
+            Shape::Triangle => "triangle".into(),
+            Shape::Plaintext => "plaintext".into(),
+            Shape::Plain => "plain".into(),
+            Shape::Diamond => "diamond".into(),
+            Shape::Trapezium => "trapezium".into(),
+            Shape::Parallelogram => "parallelogram".into(),
+            Shape::House => "house".into(),
+            Shape::Pentagon => "pentagon".into(),
+            Shape::Hexagon => "hexagon".into(),
+            Shape::Septagon => "septagon".into(),
+            Shape::Octagon => "octagon".into(),
+            Shape::DoubleCircle => "doublecircle".into(),
+            Shape::DoubleOctagon => "doubleoctagon".into(),
+            Shape::TripleOctagon => "tripleocctagon".into(),
+            Shape::Invtriangle => "invtriangle".into(),
+            Shape::Invtrapezium => "invtrapezium".into(),
+            Shape::Invhouse => "invhouse".into(),
+            Shape::Mdiamond => "mdiamond".into(),
+            Shape::Msquare => "msquare".into(),
+            Shape::Mcircle => "mcircle".into(),
+            Shape::Record => "record".into(),
+            Shape::Rect => "rect".into(),
+            Shape::Rectangle => "rectangle".into(),
+            Shape::Square => "square".into(),
+            Shape::Star => "star".into(),
+            Shape::None => "none".into(),
+            Shape::Underline => "underline".into(),
+            Shape::Cylinder => "cylinder".into(),
+            Shape::Note => "note".into(),
+            Shape::Tab => "tab".into(),
+            Shape::Folder => "folder".into(),
+            Shape::Box3D => "box3d".into(),
+            Shape::Component => "component".into(),
+            Shape::Promoter => "promoter".into(),
+            Shape::Cds => "cds".into(),
+            Shape::Terminator => "terminator".into(),
+            Shape::Utr => "utr".into(),
+            Shape::Primersite => "primersite".into(),
+            Shape::Restrictionsite => "restrictionsite".into(),
+            Shape::FivePoverHang => "fivepoverhang".into(),
+            Shape::ThreePoverHang => "threepoverhang".into(),
+            Shape::NoverHang => "noverhang".into(),
+            Shape::Assemply => "assemply".into(),
+            Shape::Signature => "signature".into(),
+            Shape::Insulator => "insulator".into(),
+            Shape::Ribosite => "ribosite".into(),
+            Shape::Rnastab => "rnastab".into(),
+            Shape::Proteasesite => "proteasesite".into(),
+            Shape::Proteinstab => "proteinstab".into(),
+            Shape::Rpromotor => "rpromotor".into(),
+            Shape::Rarrow => "rarrow".into(),
+            Shape::Larrow => "larrow".into(),
+            Shape::Lpromotor => "lpromotor".into(),
+        }
+    }
+}
diff --git a/src/attributes/spline_type.rs b/src/attributes/spline_type.rs
new file mode 100644
index 0000000..259496a
--- /dev/null
+++ b/src/attributes/spline_type.rs
@@ -0,0 +1,110 @@
+use crate::attributes::point::Point;
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// The number of points in the list must be equivalent to 1 mod 3; note that this is not checked.
+/// TODO: should we check?
+pub struct SplineType {
+    pub start: Option<Point>,
+    pub end: Option<Point>,
+    pub spline_points: Vec<Point>,
+}
+
+impl<'a> DotString<'a> for SplineType {
+    fn dot_string(&self) -> Cow<'a, str> {
+        let mut dot_string = String::from("");
+
+        if let Some(end) = &self.end {
+            dot_string.push_str(format!("e,{:.1},{:.1} ", end.x, end.y).as_str());
+        }
+
+        if let Some(start) = &self.start {
+            dot_string.push_str(format!("s,{:.1},{:.1} ", start.x, start.y).as_str());
+        }
+
+        let mut iter = self.spline_points.iter();
+        let first = iter.next().unwrap();
+        dot_string.push_str(format!("{}", first.dot_string()).as_str());
+        for point in iter {
+            dot_string.push_str(" ");
+            dot_string.push_str(format!("{}", point.dot_string()).as_str());
+        }
+
+        dot_string.into()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::attributes::{Point, SplineType};
+    use crate::DotString;
+
+    #[test]
+    fn spline_type() {
+        let spline_type = SplineType {
+            end: None,
+            start: None,
+            spline_points: vec![
+                Point::new_2d(0.0, 0.0),
+                Point::new_2d(1.0, 1.0),
+                Point::new_2d(1.0, -1.0),
+            ],
+        };
+
+        assert_eq!("0.0,0.0 1.0,1.0 1.0,-1.0", spline_type.dot_string());
+    }
+
+    #[test]
+    fn spline_type_end() {
+        let spline_type = SplineType {
+            end: Some(Point::new_2d(2.0, 0.0)),
+            start: None,
+            spline_points: vec![
+                Point::new_2d(0.0, 0.0),
+                Point::new_2d(1.0, 1.0),
+                Point::new_2d(1.0, -1.0),
+            ],
+        };
+
+        assert_eq!(
+            "e,2.0,0.0 0.0,0.0 1.0,1.0 1.0,-1.0",
+            spline_type.dot_string()
+        );
+    }
+
+    #[test]
+    fn spline_type_start() {
+        let spline_type = SplineType {
+            end: None,
+            start: Some(Point::new_2d(-1.0, 0.0)),
+            spline_points: vec![
+                Point::new_2d(0.0, 0.0),
+                Point::new_2d(1.0, 1.0),
+                Point::new_2d(1.0, -1.0),
+            ],
+        };
+
+        assert_eq!(
+            "s,-1.0,0.0 0.0,0.0 1.0,1.0 1.0,-1.0",
+            spline_type.dot_string()
+        );
+    }
+
+    #[test]
+    fn spline_type_complete() {
+        let spline_type = SplineType {
+            end: Some(Point::new_2d(2.0, 0.0)),
+            start: Some(Point::new_2d(-1.0, 0.0)),
+            spline_points: vec![
+                Point::new_2d(0.0, 0.0),
+                Point::new_2d(1.0, 1.0),
+                Point::new_2d(1.0, -1.0),
+            ],
+        };
+
+        assert_eq!(
+            "e,2.0,0.0 s,-1.0,0.0 0.0,0.0 1.0,1.0 1.0,-1.0",
+            spline_type.dot_string()
+        );
+    }
+}
diff --git a/src/attributes/splines.rs b/src/attributes/splines.rs
new file mode 100644
index 0000000..5ac9b65
--- /dev/null
+++ b/src/attributes/splines.rs
@@ -0,0 +1,31 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+/// Spline, edges are drawn as splines routed around nodes
+/// Line, edges are drawn as line segments
+/// Polygon, specifies that edges should be drawn as polylines.
+/// Ortho, specifies edges should be routed as polylines of axis-aligned segments.
+/// Curved, specifies edges should be drawn as curved arcs.
+/// splines=line and splines=spline can be used as synonyms for
+/// splines=false and splines=true, respectively.
+pub enum Splines {
+    Line,
+    Spline,
+    None,
+    Curved,
+    Polyline,
+    Ortho,
+}
+
+impl<'a> DotString<'a> for Splines {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Splines::Line => "line".into(),
+            Splines::Spline => "spline".into(),
+            Splines::None => "none".into(),
+            Splines::Curved => "curved".into(),
+            Splines::Polyline => "polyline".into(),
+            Splines::Ortho => "ortho".into(),
+        }
+    }
+}
diff --git a/src/attributes/style.rs b/src/attributes/style.rs
new file mode 100644
index 0000000..0b7fd2a
--- /dev/null
+++ b/src/attributes/style.rs
@@ -0,0 +1,92 @@
+use crate::dot::DotString;
+use std::borrow::Cow;
+
+pub enum NodeStyle {
+    Bold,
+    Dashed,
+    Diagonals,
+    Dotted,
+    Filled,
+    Invisible,
+    Rounded,
+    Solid,
+    Stripped,
+    Radical,
+    Wedged,
+}
+
+impl<'a> DotString<'a> for NodeStyle {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            NodeStyle::Bold => "bold".into(),
+            NodeStyle::Dashed => "dashed".into(),
+            NodeStyle::Diagonals => "diagonals".into(),
+            NodeStyle::Dotted => "dotted".into(),
+            NodeStyle::Filled => "filled".into(),
+            NodeStyle::Invisible => "invisible".into(),
+            NodeStyle::Rounded => "rounded".into(),
+            NodeStyle::Solid => "solid".into(),
+            NodeStyle::Stripped => "stripped".into(),
+            NodeStyle::Radical => "radical".into(),
+            NodeStyle::Wedged => "wedged".into(),
+        }
+    }
+}
+
+pub enum EdgeStyle {
+    Bold,
+    Dashed,
+    Dotted,
+    Invisible,
+    Solid,
+    Tapered,
+}
+
+impl<'a> DotString<'a> for EdgeStyle {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            EdgeStyle::Bold => "bold".into(),
+            EdgeStyle::Dashed => "dashed".into(),
+            EdgeStyle::Dotted => "dotted".into(),
+            EdgeStyle::Invisible => "invisible".into(),
+            EdgeStyle::Solid => "solid".into(),
+            EdgeStyle::Tapered => "tapered".into(),
+        }
+    }
+}
+
+pub enum GraphStyle {
+    Filled,
+    Radical,
+    Rounded,
+    Striped,
+}
+
+impl<'a> DotString<'a> for GraphStyle {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            GraphStyle::Filled => "filled".into(),
+            GraphStyle::Radical => "radical".into(),
+            GraphStyle::Rounded => "rounded".into(),
+            GraphStyle::Striped => "striped".into(),
+        }
+    }
+}
+
+// TODO: this might be a bit much to in order to avoid some duplication
+// probably not worth it but is pattern is cool nonetheless
+pub enum Styles {
+    Edge(EdgeStyle),
+    Node(NodeStyle),
+    Graph(GraphStyle),
+}
+
+impl<'a> DotString<'a> for Styles {
+    fn dot_string(&self) -> Cow<'a, str> {
+        match self {
+            Styles::Edge(s) => s.dot_string(),
+            Styles::Node(s) => s.dot_string(),
+            Styles::Graph(s) => s.dot_string(),
+        }
+    }
+}