Initial unit conversion support.

2 files changed, 88 insertions, 4 deletions

diff --git a/README b/README
index c86f394..35a6b64 100644
--- a/README
+++ b/README
@@ -6,7 +6,7 @@ If for some obscure reason, you would like to use this hackish beast, the first
 thing you need to do is create a sqlite database with the following schema:
 
 CREATE TABLE recipes (id INTEGER PRIMARY KEY AUTOINCREMENT, name, uri, servings INTEGER);
-CREATE TABLE ingredients (id INTEGER PRIMARY KEY AUTOINCREMENT, name, shop_position INTEGER);
+CREATE TABLE ingredients (id INTEGER PRIMARY KEY AUTOINCREMENT, name, shop_position INTEGER, primary_unit, density, piece_weight);
 CREATE TABLE contents (recipe_id INTEGER, ingredient_id INTEGER, quantity FLOAT, unit);
 CREATE TABLE plan (date DATETIME, mealtype, recipe_id INTEGER, state, comment_id);
 CREATE TABLE comments (id INTEGER PRIMARY KEY AUTOINCREMENT, comment);
diff --git a/mat b/mat
index 0e5c33f..e920470 100755
--- a/mat
+++ b/mat
@@ -123,6 +123,75 @@ my @schedule = (
   }
 );
 
+sub convert_to_unit {
+  my ( $out_unit, $id, $in_amount, $in_unit ) = @_;
+  my %out_amount;
+  my %convert;
+
+  # SELECT DISTINCT unit FROM contents;
+  # msk, krm, dl, tsk, cl, l, ml, nypa
+  # st, knippen, burk, paket, påse, blad, ark, skiv
+  # dm, cm, mm
+  # n/a
+  # g, kg
+
+  if      ($in_unit eq "l") {
+    $convert{'volume'} = $in_amount;
+  } elsif ($in_unit eq "dl") {
+    $convert{'volume'} = $in_amount / 10;
+  } elsif ($in_unit eq "msk") {
+    $convert{'volume'} = $in_amount * 0.015;
+  } elsif ($in_unit eq "tsk") {
+    $convert{'volume'} = $in_amount * 0.005;
+  } elsif ($in_unit eq "g") {
+    $convert{'weight'} = $in_amount;
+  } elsif ($in_unit eq "kg") {
+    $convert{'weight'} = $in_amount * 1000;
+  } elsif ($in_unit eq "st") {
+    $convert{'piece'} = $in_amount;
+  }
+
+  my $sql = "SELECT density, piece_weight FROM ingredients WHERE id=".$id.";";
+  my $ingredient = $db->selectrow_hashref($sql);
+  my $volume;
+  my $density;
+  my $weight;
+  $density = $ingredient->{density};                              # kg/m³
+  my $piece_weight;
+
+  if ( $convert{'volume'} ) {
+    $volume = 0.001 * $convert{'volume'};                            # m³
+    if ($ingredient->{density}) {
+      $out_amount{'weight'} = 1000 * $density * $volume;             # g
+    }
+  } elsif ( $convert{'weight'} ) {
+    $weight = $convert{'weight'} / 1000;                             # kg
+    if ($ingredient->{'piece_weight'}) {
+      $piece_weight = $ingredient->{'piece_weight'};                 # g/piece
+      $out_amount{'piece'} = $convert{'weight'} /
+          $ingredient->{'piece_weight'};                             # piece
+    }
+    if ($ingredient->{density}) {
+      $out_amount{'volume'} = 1000 * $weight / $density;             # g
+    }
+  } elsif ( $convert{'piece'} ) {
+    if ($ingredient->{'piece_weight'}) {
+      $piece_weight = $ingredient->{'piece_weight'};                 # g/piece
+      $out_amount{'weight'} = $convert{'piece'} * $piece_weight;     # g
+    }
+  }
+
+  if ($out_unit eq "g") {
+    return $out_amount{'weight'};
+  } elsif ($out_unit eq "st") {
+    return $out_amount{'piece'};
+  } elsif ($out_unit eq "l") {
+    return $out_amount{'volume'};
+  }
+
+  return undef;
+}
+
 sub cmd_setmeal {
   my ( $date, $mealtype, $recipe_ids ) = @_;
 
@@ -675,9 +744,24 @@ sub cmd_showrecipe {
 
   my $contents = $db->selectall_hashref("SELECT * FROM contents WHERE recipe_id=".$recipe_id.";", 'ingredient_id');
   for my $content ( keys(%$contents)) {
-    my $ingredientcol = $db->selectcol_arrayref("SELECT name FROM ingredients WHERE id=".$content.";");
-    printf "%4s %-8s %s\n", $$contents{$content}{quantity},
-        $$contents{$content}{unit}, @$ingredientcol[0];
+    my $ingredientcol = $db->selectrow_arrayref("SELECT name, primary_unit FROM ingredients WHERE id=".$content.";");
+    my $convert_unit;
+    my $convert_result;
+    if ($$contents{$content}{unit} eq "g" ) {
+      $convert_unit = @$ingredientcol[1];
+    } else {
+      $convert_unit = "g";
+    }
+    if ($convert_unit) {
+     $convert_result = convert_to_unit($convert_unit, $content, $$contents{$content}{quantity}, $$contents{$content}{unit});
+    }
+    printf "%4s %-8s ", $$contents{$content}{quantity}, $$contents{$content}{unit};
+    if ( $convert_result ) {
+      printf "(%4.4s %-8s)", $convert_result, $convert_unit;
+    } else {
+      printf "%15s", " ";
+    }
+    printf " %s\n", @$ingredientcol[0];
   }
  
   return 1;