local platform = require 'bee.platform'
local config   = require 'config'
local glob     = require 'glob'
local furi     = require 'file-uri'
local parser   = require 'parser'
local proto    = require 'proto'
local lang     = require 'language'
local await    = require 'await'

local m = {}

m.openMap = {}
m.fileMap = {}
m.watchList = {}
m.notifyCache = {}
m.assocVersion = -1
m.assocMatcher = nil
m.globalVersion = 0

--- 打开文件
---@param uri string
function m.open(uri)
    local originUri = uri
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    m.openMap[uri] = true
    m.onWatch('open', originUri)
end

--- 关闭文件
---@param uri string
function m.close(uri)
    local originUri = uri
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    m.openMap[uri] = nil
    m.onWatch('close', originUri)
end

--- 是否打开
---@param uri string
---@return boolean
function m.isOpen(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    return m.openMap[uri] == true
end

--- 是否存在
---@return boolean
function m.exists(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    return m.fileMap[uri] ~= nil
end

function m.asKey(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    return uri
end

--- 设置文件文本
---@param uri string
---@param text string
function m.setText(uri, text)
    local originUri = uri
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    if not m.fileMap[uri] then
        m.fileMap[uri] = {
            uri = originUri,
            version = 0,
        }
    end
    local file = m.fileMap[uri]
    if file.text == text then
        return
    end
    file.text  = text
    file.ast   = nil
    file.lines = nil
    file.cache = {}
    file.version = file.version + 1
    m.globalVersion = m.globalVersion + 1
    await.close('files.version')
    m.onWatch('update', originUri)
end

--- 获取文件版本
function m.getVersion(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    return file.version
end

--- 获取文件文本
---@param uri string
---@return string text
function m.getText(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    return file.text
end

--- 移除文件
---@param uri string
function m.remove(uri)
    local originUri = uri
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return
    end
    m.fileMap[uri] = nil

    m.globalVersion = m.globalVersion + 1
    await.close('files.version')
    m.onWatch('remove', originUri)
end

--- 移除所有文件
function m.removeAll()
    m.globalVersion = m.globalVersion + 1
    await.close('files.version')
    for uri in pairs(m.fileMap) do
        m.fileMap[uri] = nil
        m.onWatch('remove', uri)
    end
    m.notifyCache = {}
end

--- 遍历文件
function m.eachFile()
    return pairs(m.fileMap)
end

--- 获取文件语法树
---@param uri string
---@return table ast
function m.getAst(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    if #file.text >= config.config.workspace.maxPreload * 1000 then
        if not m.notifyCache['maxPreload'] then
            m.notifyCache['maxPreload'] = {}
        end
        if not m.notifyCache['maxPreload'][uri] then
            m.notifyCache['maxPreload'][uri] = true
            local ws = require 'workspace'
            proto.notify('window/showMessage', {
                type = 3,
                -- TODO 翻译
                message = lang.script('已跳过过大的文件：{}。当前设置的大小限制为：{} KB，该文件大小为：{} KB'
                    , ws.getRelativePath(file.uri)
                    , config.config.workspace.maxPreload
                    , #file.text / 1000
                ),
            })
        end
        file.ast = nil
        return nil
    end
    if file.ast == nil then
        local clock = os.clock()
        local state, err = parser:compile(file.text, 'lua', config.config.runtime.version)
        local passed = os.clock() - clock
        if passed > 0.1 then
            log.warn(('Compile [%s] takes [%.3f] sec, size [%.3f] kb.'):format(uri, passed, #file.text / 1000))
        end
        if state then
            state.uri = file.uri
            state.ast.uri = file.uri
            file.ast = state
        else
            log.error(err)
            file.ast = false
            return nil
        end
    end
    return file.ast
end

--- 获取文件行信息
---@param uri string
---@return table lines
function m.getLines(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    if not file.lines then
        file.lines = parser:lines(file.text)
    end
    return file.lines
end

--- 获取原始uri
function m.getOriginUri(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    return file.uri
end

function m.getUri(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    return uri
end

--- 获取文件的自定义缓存信息（在文件内容更新后自动失效）
function m.getCache(uri)
    if platform.OS == 'Windows' then
        uri = uri:lower()
    end
    local file = m.fileMap[uri]
    if not file then
        return nil
    end
    return file.cache
end

--- 判断文件名相等
function m.eq(a, b)
    if platform.OS == 'Windows' then
        return a:lower() == b:lower()
    else
        return a == b
    end
end

--- 获取文件关联
function m.getAssoc()
    if m.assocVersion == config.version then
        return m.assocMatcher
    end
    m.assocVersion = config.version
    local patt = {}
    for k, v in pairs(config.other.associations) do
        if m.eq(v, 'lua') then
            patt[#patt+1] = k
        end
    end
    m.assocMatcher = glob.glob(patt)
    if platform.OS == 'Windows' then
        m.assocMatcher:setOption 'ignoreCase'
    end
    return m.assocMatcher
end

--- 判断是否是Lua文件
---@param uri string
---@return boolean
function m.isLua(uri)
    local ext = uri:match '%.([^%.%/%\\]-)$'
    if not ext then
        return false
    end
    if m.eq(ext, 'lua') then
        return true
    end
    local matcher = m.getAssoc()
    local path = furi.decode(uri)
    return matcher(path)
end

--- 注册事件
function m.watch(callback)
    m.watchList[#m.watchList+1] = callback
end

function m.onWatch(ev, ...)
    for _, callback in ipairs(m.watchList) do
        callback(ev, ...)
    end
end

return m