local error        = error
local type         = type

---@class parser.guide.object

---@class guide
---@field debugMode boolean
local m = {}

m.ANY = {"<ANY>"}

local blockTypes = {
    ['while']       = true,
    ['in']          = true,
    ['loop']        = true,
    ['repeat']      = true,
    ['do']          = true,
    ['function']    = true,
    ['ifblock']     = true,
    ['elseblock']   = true,
    ['elseifblock'] = true,
    ['main']        = true,
}

local breakBlockTypes = {
    ['while']       = true,
    ['in']          = true,
    ['loop']        = true,
    ['repeat']      = true,
}

m.childMap = {
    ['main']        = {'#', 'docs'},
    ['repeat']      = {'#', 'filter'},
    ['while']       = {'filter', '#'},
    ['in']          = {'keys', '#'},
    ['loop']        = {'loc', 'max', 'step', '#'},
    ['if']          = {'#'},
    ['ifblock']     = {'filter', '#'},
    ['elseifblock'] = {'filter', '#'},
    ['elseblock']   = {'#'},
    ['setfield']    = {'node', 'field', 'value'},
    ['setglobal']   = {'value'},
    ['local']       = {'attrs', 'value'},
    ['setlocal']    = {'value'},
    ['return']      = {'#'},
    ['do']          = {'#'},
    ['select']      = {'vararg'},
    ['table']       = {'#'},
    ['tableindex']  = {'index', 'value'},
    ['tablefield']  = {'field', 'value'},
    ['function']    = {'args', '#'},
    ['funcargs']    = {'#'},
    ['setmethod']   = {'node', 'method', 'value'},
    ['getmethod']   = {'node', 'method'},
    ['setindex']    = {'node', 'index', 'value'},
    ['getindex']    = {'node', 'index'},
    ['paren']       = {'exp'},
    ['call']        = {'node', 'args'},
    ['callargs']    = {'#'},
    ['getfield']    = {'node', 'field'},
    ['list']        = {'#'},
    ['binary']      = {1, 2},
    ['unary']       = {1},

    ['doc']                = {'#'},
    ['doc.class']          = {'class', '#extends', 'comment'},
    ['doc.type']           = {'#types', '#enums', 'name', 'comment'},
    ['doc.alias']          = {'alias', 'extends', 'comment'},
    ['doc.param']          = {'param', 'extends', 'comment'},
    ['doc.return']         = {'#returns', 'comment'},
    ['doc.field']          = {'field', 'extends', 'comment'},
    ['doc.generic']        = {'#generics', 'comment'},
    ['doc.generic.object'] = {'generic', 'extends', 'comment'},
    ['doc.vararg']         = {'vararg', 'comment'},
    ['doc.type.array']     = {'node'},
    ['doc.type.table']     = {'node', 'key', 'value', 'comment'},
    ['doc.type.function']  = {'#args', '#returns', 'comment'},
    ['doc.type.literal']   = {'node'},
    ['doc.type.arg']       = {'extends'},
    ['doc.overload']       = {'overload', 'comment'},
    ['doc.see']            = {'name', 'field'},
}

m.actionMap = {
    ['main']        = {'#'},
    ['repeat']      = {'#'},
    ['while']       = {'#'},
    ['in']          = {'#'},
    ['loop']        = {'#'},
    ['if']          = {'#'},
    ['ifblock']     = {'#'},
    ['elseifblock'] = {'#'},
    ['elseblock']   = {'#'},
    ['do']          = {'#'},
    ['function']    = {'#'},
    ['funcargs']    = {'#'},
}

--- 是否是字面量
---@param obj parser.guide.object
---@return boolean
function m.isLiteral(obj)
    local tp = obj.type
    return tp == 'nil'
        or tp == 'boolean'
        or tp == 'string'
        or tp == 'number'
        or tp == 'table'
        or tp == 'function'
end

--- 获取字面量
---@param obj parser.guide.object
---@return any
function m.getLiteral(obj)
    local tp = obj.type
    if     tp == 'boolean' then
        return obj[1]
    elseif tp == 'string' then
        return obj[1]
    elseif tp == 'number' then
        return obj[1]
    end
    return nil
end

--- 寻找父函数
---@param obj parser.guide.object
---@return parser.guide.object
function m.getParentFunction(obj)
    for _ = 1, 1000 do
        obj = obj.parent
        if not obj then
            break
        end
        local tp = obj.type
        if tp == 'function' or tp == 'main' then
            return obj
        end
    end
    return nil
end

--- 寻找父的table类型 doc.type.table
---@param obj parser.guide.object
---@return parser.guide.object
function m.getParentDocTypeTable(obj)
    for _ = 1, 1000 do
        local parent = obj.parent
        if not parent then
            return nil
        end
        if parent.type == 'doc.type.table' then
            return obj
        end
        obj = parent
    end
    error('guide.getParentDocTypeTable overstack')
end

--- 寻找所在区块
---@param obj parser.guide.object
---@return parser.guide.object
function m.getBlock(obj)
    for _ = 1, 1000 do
        if not obj then
            return nil
        end
        local tp = obj.type
        if blockTypes[tp] then
            return obj
        end
        if obj == obj.parent then
            error('obj == obj.parent?', obj.type)
        end
        obj = obj.parent
    end
    error('guide.getBlock overstack')
end

--- 寻找所在父区块
---@param obj parser.guide.object
---@return parser.guide.object
function m.getParentBlock(obj)
    for _ = 1, 1000 do
        obj = obj.parent
        if not obj then
            return nil
        end
        local tp = obj.type
        if blockTypes[tp] then
            return obj
        end
    end
    error('guide.getParentBlock overstack')
end

--- 寻找所在可break的父区块
---@param obj parser.guide.object
---@return parser.guide.object
function m.getBreakBlock(obj)
    for _ = 1, 1000 do
        obj = obj.parent
        if not obj then
            return nil
        end
        local tp = obj.type
        if breakBlockTypes[tp] then
            return obj
        end
        if tp == 'function' then
            return nil
        end
    end
    error('guide.getBreakBlock overstack')
end

--- 寻找doc的主体
---@param obj parser.guide.object
---@return parser.guide.object
function m.getDocState(obj)
    for _ = 1, 1000 do
        local parent = obj.parent
        if not parent then
            return obj
        end
        if parent.type == 'doc' then
            return obj
        end
        obj = parent
    end
    error('guide.getDocState overstack')
end

--- 寻找所在父类型
---@param obj parser.guide.object
---@return parser.guide.object
function m.getParentType(obj, want)
    for _ = 1, 1000 do
        obj = obj.parent
        if not obj then
            return nil
        end
        if want == obj.type then
            return obj
        end
    end
    error('guide.getParentType overstack')
end

--- 寻找根区块
---@param obj parser.guide.object
---@return parser.guide.object
function m.getRoot(obj)
    local source = obj
    if source._root then
        return source._root
    end
    for _ = 1, 1000 do
        if obj.type == 'main' then
            source._root = obj
            return obj
        end
        if obj._root then
            source._root = obj._root
            return source._root
        end
        local parent = obj.parent
        if not parent then
            return nil
        end
        obj = parent
    end
    error('guide.getRoot overstack')
end

---@param obj parser.guide.object
---@return string
function m.getUri(obj)
    if obj.uri then
        return obj.uri
    end
    local root = m.getRoot(obj)
    if root then
        return root.uri
    end
    return ''
end

function m.getENV(source, start)
    if not start then
        start = 1
    end
    return m.getLocal(source, '_ENV', start)
        or m.getLocal(source, '@fenv', start)
end

--- 寻找函数的不定参数，返回不定参在第几个参数上，以及该参数对象。
--- 如果函数是主函数，则返回`0, nil`。
---@return table
---@return integer
function m.getFunctionVarArgs(func)
    if func.type == 'main' then
        return 0, nil
    end
    if func.type ~= 'function' then
        return nil, nil
    end
    local args = func.args
    if not args then
        return nil, nil
    end
    for i = 1, #args do
        local arg = args[i]
        if arg.type == '...' then
            return i, arg
        end
    end
    return nil, nil
end

--- 获取指定区块中可见的局部变量
---@param block table
---@param name string {comment = '变量名'}
---@param pos integer {comment = '可见位置'}
function m.getLocal(block, name, pos)
    block = m.getBlock(block)
    for _ = 1, 1000 do
        if not block then
            return nil
        end
        local locals = block.locals
        local res
        if not locals then
            goto CONTINUE
        end
        for i = 1, #locals do
            local loc = locals[i]
            if loc.effect > pos then
                break
            end
            if loc[1] == name then
                if not res or res.effect < loc.effect then
                    res = loc
                end
            end
        end
        if res then
            return res, res
        end
        ::CONTINUE::
        block = m.getParentBlock(block)
    end
    error('guide.getLocal overstack')
end

--- 获取指定区块中所有的可见局部变量名称
function m.getVisibleLocals(block, pos)
    local result = {}
    m.eachSourceContain(m.getRoot(block), pos, function (source)
        local locals = source.locals
        if locals then
            for i = 1, #locals do
                local loc = locals[i]
                local name = loc[1]
                if loc.effect <= pos then
                    result[name] = loc
                end
            end
        end
    end)
    return result
end

--- 获取指定区块中可见的标签
---@param block table
---@param name string {comment = '标签名'}
function m.getLabel(block, name)
    block = m.getBlock(block)
    for _ = 1, 1000 do
        if not block then
            return nil
        end
        local labels = block.labels
        if labels then
            local label = labels[name]
            if label then
                return label
            end
        end
        if block.type == 'function' then
            return nil
        end
        block = m.getParentBlock(block)
    end
    error('guide.getLocal overstack')
end

function m.getStartFinish(source)
    local start  = source.start
    local finish = source.finish
    if not start then
        local first = source[1]
        if not first then
            return nil, nil
        end
        local last  = source[#source]
        start  = first.start
        finish = last.finish
    end
    return start, finish
end

function m.getRange(source)
    local start  = source.vstart or source.start
    local finish = source.range  or source.finish
    if not start then
        local first = source[1]
        if not first then
            return nil, nil
        end
        local last  = source[#source]
        start  = first.vstart or first.start
        finish = last.range   or last.finish
    end
    return start, finish
end

--- 判断source是否包含offset
function m.isContain(source, offset)
    local start, finish = m.getStartFinish(source)
    if not start then
        return false
    end
    return start <= offset and finish >= offset
end

--- 判断offset在source的影响范围内
---
--- 主要针对赋值等语句时，key包含value
function m.isInRange(source, offset)
    local start, finish = m.getRange(source)
    if not start then
        return false
    end
    return start <= offset and finish >= offset
end

function m.isBetween(source, tStart, tFinish)
    local start, finish = m.getStartFinish(source)
    if not start then
        return false
    end
    return start <= tFinish and finish >= tStart
end

function m.isBetweenRange(source, tStart, tFinish)
    local start, finish = m.getRange(source)
    if not start then
        return false
    end
    return start <= tFinish and finish >= tStart
end

--- 添加child
function m.addChilds(list, obj, map)
    local keys = map[obj.type]
    if keys then
        for i = 1, #keys do
            local key = keys[i]
            if key == '#' then
                for j = 1, #obj do
                    list[#list+1] = obj[j]
                end
            elseif obj[key] then
                list[#list+1] = obj[key]
            elseif type(key) == 'string'
            and key:sub(1, 1) == '#' then
                key = key:sub(2)
                if obj[key] then
                    for j = 1, #obj[key] do
                        list[#list+1] = obj[key][j]
                    end
                end
            end
        end
    end
end

--- 遍历所有包含offset的source
function m.eachSourceContain(ast, offset, callback)
    local list = { ast }
    local mark = {}
    while true do
        local len = #list
        if len == 0 then
            return
        end
        local obj = list[len]
        list[len] = nil
        if not mark[obj] then
            mark[obj] = true
            if m.isInRange(obj, offset) then
                if m.isContain(obj, offset) then
                    local res = callback(obj)
                    if res ~= nil then
                        return res
                    end
                end
                m.addChilds(list, obj, m.childMap)
            end
        end
    end
end

--- 遍历所有在某个范围内的source
function m.eachSourceBetween(ast, start, finish, callback)
    local list = { ast }
    local mark = {}
    while true do
        local len = #list
        if len == 0 then
            return
        end
        local obj = list[len]
        list[len] = nil
        if not mark[obj] then
            mark[obj] = true
            if m.isBetweenRange(obj, start, finish) then
                if m.isBetween(obj, start, finish) then
                    local res = callback(obj)
                    if res ~= nil then
                        return res
                    end
                end
                m.addChilds(list, obj, m.childMap)
            end
        end
    end
end

--- 遍历所有指定类型的source
function m.eachSourceType(ast, type, callback)
    local cache = ast.typeCache
    if not cache then
        cache = {}
        ast.typeCache = cache
        m.eachSource(ast, function (source)
            local tp = source.type
            if not tp then
                return
            end
            local myCache = cache[tp]
            if not myCache then
                myCache = {}
                cache[tp] = myCache
            end
            myCache[#myCache+1] = source
        end)
    end
    local myCache = cache[type]
    if not myCache then
        return
    end
    for i = 1, #myCache do
        callback(myCache[i])
    end
end

--- 遍历所有的source
function m.eachSource(ast, callback)
    local list = { ast }
    local mark = {}
    local index = 1
    while true do
        local obj = list[index]
        if not obj then
            return
        end
        list[index] = false
        index = index + 1
        if not mark[obj] then
            mark[obj] = true
            callback(obj)
            m.addChilds(list, obj, m.childMap)
        end
    end
end

--- 获取指定的 special
function m.eachSpecialOf(ast, name, callback)
    local root = m.getRoot(ast)
    if not root.specials then
        return
    end
    local specials = root.specials[name]
    if not specials then
        return
    end
    for i = 1, #specials do
        callback(specials[i])
    end
end

--- 获取偏移对应的坐标
---@param lines table
---@return integer {name = 'row'}
---@return integer {name = 'col'}
function m.positionOf(lines, offset)
    if offset < 1 then
        return 0, 0
    end
    local lastLine = lines[#lines]
    if offset > lastLine.finish then
        return #lines, offset - lastLine.start
    end
    local min = 1
    local max = #lines
    for _ = 1, 100 do
        if max <= min then
            local line = lines[min]
            return min, offset - line.start + 1
        end
        local row = (max - min) // 2 + min
        local line = lines[row]
        if offset < line.start then
            max = row - 1
        elseif offset > line.finish then
            min = row + 1
        else
            return row, offset - line.start + 1
        end
    end
    error('Stack overflow!')
end

--- 获取坐标对应的偏移
---@param lines table
---@param row integer
---@param col integer
---@return integer {name = 'offset'}
function m.offsetOf(lines, row, col)
    if row < 1 then
        return 0
    end
    if row > #lines then
        local lastLine = lines[#lines]
        return lastLine.finish
    end
    local line = lines[row]
    local len = line.finish - line.start + 1
    if col < 0 then
        return line.start
    elseif col > len then
        return line.finish
    else
        return line.start + col - 1
    end
end

function m.lineContent(lines, text, row, ignoreNL)
    local line = lines[row]
    if not line then
        return ''
    end
    if ignoreNL then
        return text:sub(line.start, line.range)
    else
        return text:sub(line.start, line.finish)
    end
end

function m.lineRange(lines, row, ignoreNL)
    local line = lines[row]
    if not line then
        return 0, 0
    end
    if ignoreNL then
        return line.start, line.range
    else
        return line.start, line.finish
    end
end

function m.lineData(lines, row)
    return lines[row]
end

return m