local files   = require 'files'
local util    = require 'utility'
local guide   = require 'parser.guide'
local vm      = require 'vm.vm'

local function getTypesOfFile(uri)
    local types = {}
    local ast = files.getAst(uri)
    if not ast or not ast.ast.docs then
        return types
    end
    guide.eachSource(ast.ast.docs, function (src)
        if src.type == 'doc.type.name'
        or src.type == 'doc.class.name'
        or src.type == 'doc.extends.name'
        or src.type == 'doc.alias.name' then
            local name = src[1]
            if name then
                if not types[name] then
                    types[name] = {}
                end
                types[name][#types[name]+1] = src
            end
        end
    end)
    return types
end

local function getDocTypes(name)
    local results = {}
    for uri in files.eachFile() do
        local cache = files.getCache(uri)
        cache.classes = cache.classes or getTypesOfFile(uri)
        if name == '*' then
            for _, sources in util.sortPairs(cache.classes) do
                for _, source in ipairs(sources) do
                    results[#results+1] = source
                end
            end
        else
            if cache.classes[name] then
                for _, source in ipairs(cache.classes[name]) do
                    results[#results+1] = source
                end
            end
        end
    end
    return results
end

function vm.getDocTypes(name)
    local cache = vm.getCache('getDocTypes')[name]
    if cache ~= nil then
        return cache
    end
    cache = getDocTypes(name)
    vm.getCache('getDocTypes')[name] = cache
    return cache
end