--[====================================================================================================================[


Example:
	require('I2CETUpdater')
	CETUpdater.checkTableVersion(versionUrl, tableVersion, tableName)
Example:
	require('I2CETUpdater')
	CETUpdater.TableVersion = '3.0.8'
	CETUpdater.TableName = 'mgsvtpp'
	CETUpdater.VersionUrl = 'https://docs.google.com/document/d/1pPgHNGV1-EmIpfxxXp0vnoeoZxlCg11ofdV1x78bJEw/export?format=txt'
	CETUpdater.checkTableVersion()

Example:
	require('I2CETUpdater')
	CETUpdater.checkTableVersion('https://docs.google.com/document/d/1pPgHNGV1-EmIpfxxXp0vnoeoZxlCg11ofdV1x78bJEw/export?format=txt', 
								 '3.0.8', 'mgsvtpp')


]====================================================================================================================]--


local NAME = 'I2 Cheat Engine Table Updater'
local CLASS_NAME = 'I2CETUpdater'
local VERSION = '1.0.4'
local AUTHOR = 'Matt Irwin; Matt.Irwin.US@Gmail.com'
local LICENSE = [=[MIT License

Copyright (c) 2018 Matt Irwin

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sub-license, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
]=]


local format = string.format
local strE = string.empty or STRING_EMPTY or ''
local t = translate


-- local Logger = {
-- 	LEVELS = {
-- 		OFF = 0, 
-- 		FATAL = 1, 
-- 		ERROR = 2, 
-- 		WARN = 3, 
-- 		INFO = 4, 
-- 		DEBUG = 5, 
-- 		TRACE = 6
-- 	}, 
-- }
-- for k, v in pairs(Logger.LEVELS) do
-- 	-- Logger[k:lower()] = function( ... ) return end
-- 	-- Logger[k:lower() .. 'f'] = function( ... ) return end
-- 	Logger[k:lower()] = function(msg, ex) return print(msg, ex) end
-- 	Logger[k:lower() .. 'f'] = function(msg, ... ) return print(string.format(msg, ... )) end
-- end
local Logger = Logger
if Logger == nil then
	if type(CETrequire) == 'function' then
		Logger = CETrequire('I2CETLogger')
	else
		Logger = require('I2CETLogger')
	end
	Logger.LogName = 'CETupdater'
end

local function split(s, delimiter)
	result = {}
	for match in (s .. delimiter):gmatch('(.-)' .. delimiter) do
		table.insert(result, match)
	end
	return result
end

local function interp(s, tbl)
	if s == nil then return end
	return (s:gsub('($%b{})', function(w) return tbl[w:sub(3, -2)] or w end))
end

local defaultFileExtension = 'CT'

CETUpdater = {
	Name = NAME, 
	ClassName = CLASS_NAME, 
	Version = VERSION, 
	Author = AUTHOR, 
	License = LICENSE,
	TableVersion = TABLE_VERSION,
	TableName = TABLE_TITLE, 
	TableUrl = TABLE_URL, 
	VersionUrl = VERSION_URL, 
	FileExtension = defaultFileExtension, 
	DefaultVersion = '1.0.1', 
	FileNameFormat = '${FileName}.[v${Version}].${FileExtension}', 
}

function CETUpdater.getVersionNumber(versionString)
	local vers = { string.match(versionString, '(%d+)%.(%d+)%.(%d+)') }
	local verStr = ''
	for i = 1, #vers do
		verStr = format('%s%08X', verStr, tonumber(vers[i]))
	end
	return tonumber(verStr, 16)
end

function CETUpdater.isTableToDownLoad(versionUrl, tableVersion)
	versionUrl = versionUrl or CETUpdater.VersionUrl
	local tableVersionStr = tableVersion or CETUpdater.TableVersion
	tableVersion = CETUpdater.getVersionNumber(tableVersionStr)
	---- ADD: nil check
	local iNet = getInternet()
	local text = iNet.getURL(versionUrl)
	iNet.destroy()
	if text then
		local args = split(text:gsub('\r\n', '\n'), '\n')
		local version = CETUpdater.getVersionNumber(args[1])
		local url = args[2]
		return (version > tableVersion), tableVersionStr, url
	else
		Logger.errorf('Unable to download version file; at: "%s"', versionUrl)
		return nil
	end
end

function CETUpdater.getNewTable(versionStr, tableUrl, tableName)
	versionStr = versionStr or CETUpdater.DefaultVersion
	tableUrl = tableUrl or CETUpdater.TableUrl
	tableName = tableName or CETUpdater.TableName or CETUpdater.ClassName
	---- ADD: nil check
	local iNet = getInternet()
	local newTableStr = iNet.getURL(tableUrl)
	if newTableStr ~= nil then
		newTableStr = newTableStr:gsub('\r\n', '\n')
		local tbl = {
			TrainerOrigin = TrainerOrigin, 
			Process = process, 
			Temp = os.getenv('TEMP') .. package.config:sub(1,1), 
			FileName = tableName or strE, 
			Version = versionStr or strE, 
			FileExtension = CETUpdater.FileExtension or defaultFileExtension, 
		}
		local newTablePath = interp(CETUpdater.FileNameFormat, tbl)
		local f, err = io.open(newTablePath, 'w')
		if f and not err then
			f:write(newTableStr)
			f:close()
			Logger.infof('New table/trainer downloaded; from: "%s", to: "%s"', tableUrl, newTablePath)
			loadTable(newTablePath)
		else
			Logger.errorf('Unable to create temp file for new table/trainer; at: "%s"', newTablePath)
		end
	else
		Logger.errorf('Unable to download latest table/trainer file; at: "%s"', tableUrl)
	end
	iNet.destroy()
end


function CETUpdater.checkTableVersion(versionUrl, tableVersion, tableName)
	local downloadTable, versionStr, url = CETUpdater.isTableToDownLoad(versionUrl, tableVersion)
	if downloadTable then
		local answer = messageDialog(t('There is a newer version of this table/trainer.') .. '\n' 
					.. format('At: "%s"', url) .. '\n' 
					.. t('Would you like to download it now?'), mtWarning, mbYes, mbNo)
		if answer == mrYes then
			CETUpdater.getNewTable(versionStr, url, tableName)
			messageDialog(t('Be sure to save the new table/trainer!'), mtInformation, mbOK)
		end
	else
		messageDialog(format(t('You currently have the latest version') .. ', "%s"', versionStr), 
					  mtInformation, mbOK)
	end
end

return CETUpdater