local fs      = require 'bee.filesystem'
local plat    = require 'bee.platform'
local config  = require 'config'
local util    = require 'utility'
local lang    = require 'language'
local client  = require 'client'
local lloader = require 'locale-loader'
local fsu     = require 'fs-utility'
local define  = require "proto.define"
local files   = require 'files'
local await   = require 'await'
local timer   = require 'timer'
local encoder = require 'encoder'
local ws      = require 'workspace.workspace'
local scope   = require 'workspace.scope'
local inspect = require 'inspect'

local m = {}

m.metaPaths = {}

local function getDocFormater(uri)
    local version = config.get(uri, 'Lua.runtime.version')
    if client.isVSCode() then
        if version == 'Lua 5.1' then
            return 'HOVER_NATIVE_DOCUMENT_LUA51'
        elseif version == 'Lua 5.2' then
            return 'HOVER_NATIVE_DOCUMENT_LUA52'
        elseif version == 'Lua 5.3' then
            return 'HOVER_NATIVE_DOCUMENT_LUA53'
        elseif version == 'Lua 5.4' then
            return 'HOVER_NATIVE_DOCUMENT_LUA54'
        elseif version == 'LuaJIT' then
            return 'HOVER_NATIVE_DOCUMENT_LUAJIT'
        end
    else
        if version == 'Lua 5.1' then
            return 'HOVER_DOCUMENT_LUA51'
        elseif version == 'Lua 5.2' then
            return 'HOVER_DOCUMENT_LUA52'
        elseif version == 'Lua 5.3' then
            return 'HOVER_DOCUMENT_LUA53'
        elseif version == 'Lua 5.4' then
            return 'HOVER_DOCUMENT_LUA54'
        elseif version == 'LuaJIT' then
            return 'HOVER_DOCUMENT_LUAJIT'
        end
    end
end

local function convertLink(uri, text)
    local fmt = getDocFormater(uri)
    return text:gsub('%$([%.%w]+)', function (name)
        local lastDot = ''
        if name:sub(-1) == '.' then
            name = name:sub(1, -2)
            lastDot = '.'
        end
        if fmt then
            return ('[%s](%s)'):format(name, lang.script(fmt, 'pdf-' .. name)) .. lastDot
        else
            return ('`%s`'):format(name) .. lastDot
        end
    end):gsub('§([%.%w]+)', function (name)
        local lastDot = ''
        if name:sub(-1) == '.' then
            name = name:sub(1, -2)
            lastDot = '.'
        end
        if fmt then
            return ('[§%s](%s)'):format(name, lang.script(fmt, name)) .. lastDot
        else
            return ('`%s`'):format(name) .. lastDot
        end
    end)
end

local function createViewDocument(name)
    local fmt = getDocFormater()
    if not fmt then
        return nil
    end
    name = name:match '[%w_%.]+'
    if name:sub(-1) == '.' then
        name = name:sub(1, -2)
    end
    return ('[%s](%s)'):format(lang.script.HOVER_VIEW_DOCUMENTS, lang.script(fmt, 'pdf-' .. name))
end

local function compileSingleMetaDoc(uri, script, metaLang, status)
    if not script then
        log.error('no meta?', uri)
        return nil
    end

    local middleBuf = {}
    local compileBuf = {}

    local last = 1
    for start, lua, finish in script:gmatch '()%-%-%-%#([^\n\r]*)()' do
        middleBuf[#middleBuf+1] = ('PUSH [===[%s]===]'):format(script:sub(last, start - 1))
        middleBuf[#middleBuf+1] = lua
        last = finish
    end
    middleBuf[#middleBuf+1] = ('PUSH [===[%s]===]'):format(script:sub(last))
    local middleScript = table.concat(middleBuf, '\n')
    local version, jit
    if config.get(uri, 'Lua.runtime.version') == 'LuaJIT' then
        version = 5.1
        jit = true
    else
        version = tonumber(config.get(uri, 'Lua.runtime.version'):sub(-3)) or 5.4
        jit = false
    end

    local disable = false
    local env = setmetatable({
        VERSION = version,
        JIT     = jit,
        PUSH    = function (text)
            compileBuf[#compileBuf+1] = text
        end,
        DES     = function (name)
            local des = metaLang[name]
            if not des then
                des = ('Miss locale <%s>'):format(name)
            end
            compileBuf[#compileBuf+1] = '---\n'
            for line in util.eachLine(des) do
                compileBuf[#compileBuf+1] = '---'
                compileBuf[#compileBuf+1] = convertLink(uri, line)
                compileBuf[#compileBuf+1] = '\n'
            end
            local viewDocument = createViewDocument(name)
            if viewDocument then
                compileBuf[#compileBuf+1] = '---\n---'
                compileBuf[#compileBuf+1] = viewDocument
                compileBuf[#compileBuf+1] = '\n'
            end
            compileBuf[#compileBuf+1] = '---\n'
        end,
        DESTAIL = function (name)
            local des = metaLang[name]
            if not des then
                des = ('Miss locale <%s>'):format(name)
            end
            compileBuf[#compileBuf+1] = convertLink(uri, des)
            compileBuf[#compileBuf+1] = '\n'
        end,
        ALIVE   = function (str)
            local isAlive
            for piece in str:gmatch '[^%,]+' do
                if piece:sub(1, 1) == '>' then
                    local alive = tonumber(piece:sub(2))
                    if not alive or version >= alive then
                        isAlive = true
                        break
                    end
                elseif piece:sub(1, 1) == '<' then
                    local alive = tonumber(piece:sub(2))
                    if not alive or version <= alive then
                        isAlive = true
                        break
                    end
                else
                    local alive = tonumber(piece)
                    if not alive or version == alive then
                        isAlive = true
                        break
                    end
                end
            end
            if not isAlive then
                compileBuf[#compileBuf+1] = '---@deprecated\n'
            end
        end,
        DISABLE = function ()
            disable = true
        end,
    }, { __index = _ENV })

    util.saveFile((ROOT / 'log' / 'middleScript.lua'):string(), middleScript)

    local suc = xpcall(function ()
        assert(load(middleScript, middleScript, 't', env))()
    end, log.error)
    if not suc then
        log.debug('MiddleScript:\n', middleScript)
    end
    if disable and status == 'default' then
        return nil
    end
    return table.concat(compileBuf)
end

local function loadMetaLocale(langID, result)
    result = result or {}
    local path = (ROOT / 'locale' / langID / 'meta.lua'):string()
    local localeContent = util.loadFile(path)
    if localeContent then
        xpcall(lloader, log.error, localeContent, path, result)
    end
    return result
end

local function initBuiltIn(uri)
    log.info('Init builtin library at:', uri)
    local scp      = scope.getScope(uri)
    local langID   = lang.id
    local version  = config.get(uri, 'Lua.runtime.version')
    local encoding = config.get(uri, 'Lua.runtime.fileEncoding')
    ---@type fs.path
    local metaPath = fs.path(METAPATH) / config.get(uri, 'Lua.runtime.meta'):gsub('%$%{(.-)%}', {
        version  = version,
        language = langID,
        encoding = encoding,
    })

    local metaLang = loadMetaLocale('en-US')
    if langID ~= 'en-US' then
        loadMetaLocale(langID, metaLang)
    end

    if scp:get('metaPath') == metaPath:string() then
        log.debug('Has meta path, skip:', metaPath:string())
        return
    end
    scp:set('metaPath', metaPath:string())
    local suc = xpcall(function ()
        if not fs.exists(metaPath) then
            fs.create_directories(metaPath)
        end
    end, log.error)
    if not suc then
        log.warn('Init builtin failed.')
        return
    end
    local out = fsu.dummyFS()
    local templateDir = ROOT / 'meta' / 'template'
    for libName, status in pairs(define.BuiltIn) do
        status = config.get(uri, 'Lua.runtime.builtin')[libName] or status
        log.debug('Builtin status:', libName, status)
        if status == 'disable' then
            goto CONTINUE
        end
        libName = libName .. '.lua'
        ---@type fs.path
        local libPath = templateDir / libName
        local metaDoc = compileSingleMetaDoc(uri, fsu.loadFile(libPath), metaLang, status)
        if metaDoc then
            metaDoc = encoder.encode(encoding, metaDoc, 'auto')
            out:saveFile(libName, metaDoc)
            local outputPath = metaPath / libName
            m.metaPaths[outputPath:string()] = true
            log.debug('Meta path:', outputPath:string())
        end
        ::CONTINUE::
    end
    local result = fsu.fileSync(out, metaPath)
    if #result.err > 0 then
        log.warn('File sync error:', inspect(result))
    end
end

---@param libraryDir fs.path
local function loadSingle3rdConfig(libraryDir)
    local configText = fsu.loadFile(libraryDir / 'config.lua')
    if not configText then
        return nil
    end

    local env = setmetatable({}, { __index = _G })
    assert(load(configText, '@' .. libraryDir:string(), 't', env))()

    local cfg = {}

    cfg.path = libraryDir:filename():string()
    cfg.name = cfg.name or cfg.path

    if fs.exists(libraryDir / 'plugin.lua') then
        cfg.plugin = true
    end

    for k, v in pairs(env) do
        cfg[k] = v
    end

    if cfg.words then
        for i, word in ipairs(cfg.words) do
            cfg.words[i] = '()' .. word .. '()'
        end
    end
    if cfg.files then
        for i, filename in ipairs(cfg.files) do
            if plat.OS == 'Windows' then
                filename = filename:gsub('/', '\\')
            else
                filename = filename:gsub('\\', '/')
            end
            cfg.files[i] = '()' .. filename .. '()'
        end
    end

    return cfg
end

local innerThirdDir = ROOT / 'meta' / '3rd'

local function load3rdConfigInDir(dir, configs, inner)
    if not fs.is_directory(dir) then
        return
    end
    for libraryDir in fs.pairs(dir) do
        local suc, res = xpcall(loadSingle3rdConfig, log.error, libraryDir)
        if suc and res then
            if inner then
                res.dirname = ('${3rd}/%s'):format(res.path)
            else
                res.dirname = ('%s/%s'):format(dir:string(), res.path)
            end
            configs[#configs+1] = res
        end
    end
end

local function load3rdConfig(uri)
    local configs = {}
    load3rdConfigInDir(innerThirdDir, configs, true)
    local thirdDirs = config.get(uri, 'Lua.workspace.userThirdParty')
    for _, thirdDir in ipairs(thirdDirs) do
        load3rdConfigInDir(fs.path(thirdDir), configs)
    end
    return configs
end

local function apply3rd(uri, cfg, onlyMemory)
    local changes = {}
    if cfg.configs then
        for _, change in ipairs(cfg.configs) do
            changes[#changes+1] = {
                key    = change.key,
                action = change.action,
                prop   = change.prop,
                value  = change.value,
                uri    = uri,
            }
        end
    end

    if cfg.plugin then
        changes[#changes+1] = {
            key    = 'Lua.runtime.plugin',
            action = 'set',
            value  = ('%s/plugin.lua'):format(cfg.dirname),
            uri    = uri,
        }
    end

    changes[#changes+1] = {
        key    = 'Lua.workspace.library',
        action = 'add',
        value  = ('%s/library'):format(cfg.dirname),
        uri    = uri,
    }

    client.setConfig(changes, onlyMemory)
end

local hasAsked
---@async
local function askFor3rd(uri, cfg)
    if hasAsked then
        return nil
    end
    hasAsked = true
    local yes1 = lang.script.WINDOW_APPLY_WHIT_SETTING
    local yes2 = lang.script.WINDOW_APPLY_WHITOUT_SETTING
    local no   = lang.script.WINDOW_DONT_SHOW_AGAIN
    local result = client.awaitRequestMessage('Info'
        , lang.script('WINDOW_ASK_APPLY_LIBRARY', cfg.name)
        , {yes1, yes2, no}
    )
    if not result then
        return nil
    end
    if result == yes1 then
        apply3rd(uri, cfg, false)
        client.setConfig({
            {
                key    = 'Lua.workspace.checkThirdParty',
                action = 'set',
                value  = false,
                uri    = uri,
            },
        }, false)
    elseif result == yes2 then
        apply3rd(uri, cfg, true)
        client.setConfig({
            {
                key    = 'Lua.workspace.checkThirdParty',
                action = 'set',
                value  = false,
                uri    = uri,
            },
        }, true)
    end
end

---@param a string
---@param b string
---@return boolean
local function wholeMatch(a, b)
    local pos1, pos2 = a:match(b)
    if not pos1 then
        return false
    end
    local left  = a:sub(pos1 - 1, pos1 - 1)
    local right = a:sub(pos2, pos2)
    if left:match '[%w_]'
    or right:match '[%w_]' then
        return false
    end
    return true
end

local function check3rdByWords(uri, configs)
    if hasAsked then
        return
    end
    if not files.isLua(uri) then
        return
    end
    local id = 'check3rdByWords:' .. uri
    await.close(id)
    await.call(function () ---@async
        await.sleep(0.1)
        local text = files.getText(uri)
        if not text then
            return
        end
        for _, cfg in ipairs(configs) do
            if cfg.words then
                for _, word in ipairs(cfg.words) do
                    await.delay()
                    if wholeMatch(text, word) then
                        askFor3rd(uri, cfg)
                        return
                    end
                end
            end
        end
    end, id)
end

local function check3rdByFileName(uri, configs)
    if hasAsked then
        return
    end
    local path = ws.getRelativePath(uri)
    if not path then
        return
    end
    local id = 'check3rdByFileName:' .. uri
    await.close(id)
    await.call(function () ---@async
        await.sleep(0.1)
        for _, cfg in ipairs(configs) do
            if cfg.files then
                for _, filename in ipairs(cfg.files) do
                    await.delay()
                    if wholeMatch(path, filename) then
                        askFor3rd(uri, cfg)
                        return
                    end
                end
            end
        end
    end, id)
end

local thirdConfigs
local function check3rd(uri)
    if hasAsked then
        return
    end
    if not config.get(uri, 'Lua.workspace.checkThirdParty') then
        return
    end
    if thirdConfigs == nil then
        thirdConfigs = load3rdConfig(uri) or false
    end
    if not thirdConfigs then
        return
    end
    check3rdByWords(uri, thirdConfigs)
    check3rdByFileName(uri, thirdConfigs)
end

local function check3rdOfWorkspace(suri)
    for uri in files.eachFile(suri) do
        check3rd(uri)
    end
    for uri in files.eachDll() do
        check3rd(uri)
    end
end

config.watch(function (uri, key, value, oldValue)
    if key:find '^Lua.runtime' then
        initBuiltIn(uri)
    end
    if key == 'Lua.workspace.checkThirdParty'
    or key == 'Lua.workspace.userThirdParty' then
        check3rdOfWorkspace(uri)
    end
end)

files.watch(function (ev, uri)
    if ev == 'update'
    or ev == 'dll' then
        check3rd(uri)
    end
end)

function m.init()
    initBuiltIn(nil)
    for _, scp in ipairs(ws.folders) do
        initBuiltIn(scp.uri)
    end
end

return m