coffee = require("coffee-script")
fs = require "fs"
spawn = require("child_process").spawn
exec = require("child_process").exec
rimraf = require "rimraf"
Path = require "path"
semver = require "semver"
knox = require "knox"
crypto = require "crypto"
async = require "async"
settings = require("settings-sharelatex")
_ = require("underscore")


SERVICES = require("./config/services")

module.exports = (grunt) ->
	grunt.loadNpmTasks 'grunt-bunyan'
	grunt.loadNpmTasks 'grunt-execute'
	grunt.loadNpmTasks 'grunt-available-tasks'
	grunt.loadNpmTasks 'grunt-concurrent'
	grunt.loadNpmTasks "grunt-contrib-coffee"
	grunt.loadNpmTasks "grunt-shell"

	grunt.task.loadTasks "./tasks"

	execute = {}
	for service in SERVICES
		execute[service.name] =
			src: "#{service.name}/app.js"

	grunt.initConfig
		execute: execute

		concurrent:
			all:
				tasks: ("run:#{service.name}" for service in SERVICES)
				options:
					limit: SERVICES.length
					logConcurrentOutput: true

		availabletasks:
			tasks:
				options:
					filter: 'exclude',
					tasks: [
						'concurrent'
						'execute'
						'bunyan'
						'availabletasks'
						]
					groups:
						"Run tasks": [
							"run"
							"run:all"
							"default"
						].concat ("run:#{service.name}" for service in SERVICES)
						"Misc": [
							"help"
						]
						"Install tasks": ("install:#{service.name}" for service in SERVICES).concat(["install:all", "install"])
						"Update tasks": ("update:#{service.name}" for service in SERVICES).concat(["update:all", "update"])
						"Checks": ["check", "check:redis", "check:latexmk", "check:s3", "check:make", "check:mongo"]

	for service in SERVICES
		do (service) ->
			grunt.registerTask "install:#{service.name}", "Download and set up the #{service.name} service", () ->
				done = @async()
				Helpers.installService(service, done)



	grunt.registerTask 'install:all', "Download and set up all ShareLaTeX services",
		[].concat(
			("install:#{service.name}" for service in SERVICES)
		).concat(['postinstall'])

	grunt.registerTask 'install', 'install:all'
	grunt.registerTask 'postinstall', 'Explain postinstall steps', () ->
		Helpers.postinstallMessage @async()

	grunt.registerTask 'update:all', "Checkout and update all ShareLaTeX services",
		["check:make"].concat(
			("update:#{service.name}" for service in SERVICES)
		)
	grunt.registerTask 'update', 'update:all'
	grunt.registerTask 'run', "Run all of the sharelatex processes", ['concurrent:all']
	grunt.registerTask 'run:all', 'run'

	grunt.registerTask 'help', 'Display this help list', 'availabletasks'
	grunt.registerTask 'default', 'run'

	grunt.registerTask "check:redis", "Check that redis is installed and running", () ->
		Helpers.checkRedisConnect @async()

	grunt.registerTask "check:mongo", "Check that mongo is installed", () ->
		Helpers.checkMongoConnect @async()

	grunt.registerTask "check", "Check that you have the required dependencies installed", ["check:redis", "check:mongo", "check:make"]

	grunt.registerTask "check:make", "Check that make is installed", () ->
		Helpers.checkMake @async()


	Helpers =
		installService: (service, callback = (error) ->) ->
			console.log "Installing #{service.name}"
			Helpers.cloneGitRepo service, (error) ->
				if error?
					callback(error)
				else
					callback()

		cloneGitRepo: (service, callback = (error) ->) ->
			repo_src = service.repo
			dir = service.name
			if !fs.existsSync(dir)
				proc = spawn "git", [
					"clone",
					repo_src,
					dir
				], stdio: "inherit"
				proc.on "close", () ->
					Helpers.checkoutVersion service, callback
			else
				console.log "#{dir} already installed, skipping."
				callback()

		checkoutVersion: (service, callback = (error) ->) ->
			dir = service.name
			grunt.log.write "checking out #{service.name} #{service.version}"
			proc = spawn "git", ["checkout", service.version], stdio: "inherit", cwd: dir
			proc.on "close", () ->
				callback()

		postinstallMessage: (callback = (error) ->) ->
			grunt.log.write """
			Services cloned:
				#{service.name for service in SERVICES}
			To install services run:
				$ source bin/install-services
			This will install the required node versions and run `npm install` for each service.
			See https://github.com/sharelatex/sharelatex/pull/549 for more info.
			"""
			callback()

		checkMake: (callback = (error) ->) ->
			grunt.log.write "Checking make is installed... "
			exec "make --version", (error, stdout, stderr) ->
				if error? and error.message.match("not found")
					grunt.log.error "FAIL."
					grunt.log.errorlns """
					Either make is not installed or is not in your path.

					On Ubuntu you can install make with:

					    sudo apt-get install build-essential

					"""
					return callback(error)
				else if error?
					return callback(error)
				else
					grunt.log.write "OK."
					return callback()
		checkMongoConnect: (callback = (error) ->) ->
			grunt.log.write "Checking can connect to mongo"
			mongojs = require("mongojs")
			db = mongojs(settings.mongo.url, ["tags"])
			db.runCommand { ping: 1 }, (err, res) ->
				if !err and res.ok
					grunt.log.write "OK."
				return callback()
			db.on 'error', (err)->
				err = "Can not connect to mongodb"
				grunt.log.error "FAIL."
				grunt.log.errorlns """
				!!!!!!!!!!!!!! MONGO ERROR !!!!!!!!!!!!!!

				ShareLaTeX can not talk to the mongodb instance

				Check the mongodb instance is running and accessible on env var SHARELATEX_MONGO_URL
				
				!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
				"""
				throw new Error("Can not connect to Mongodb")
				return callback(err)

		checkRedisConnect: (callback = (error) ->) ->
			grunt.log.write "Checking can connect to redis\n"
			rclient = require("redis").createClient(settings.redis.web)

			rclient.ping (err, res) ->
				if !err?
					grunt.log.write "OK."
				else
					throw new Error("Can not connect to redis")
				return callback()
			errorHandler = _.once (err)->
				err = "Can not connect to redis"
				grunt.log.error "FAIL."
				grunt.log.errorlns """
				!!!!!!!!!!!!!! REDIS ERROR !!!!!!!!!!!!!!

				ShareLaTeX can not talk to the redis instance

				Check the redis instance is running and accessible on env var SHARELATEX_REDIS_HOST

				!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
				"""
				throw new Error("Can not connect to redis")
				return callback(err)
			rclient.on 'error', errorHandler