#!/usr/bin/env ruby

require 'rubygems'
require 'yaml'
require 'telegram/bot'
require 'pp'
require 'time'
require_relative 'commands.rb'
require_relative 'colors.rb'

def timestamp
    Time.now.strftime("%F %H:%M:%S").yellow
end

#conf = YAML.load(File.read("bot_config.yaml"))
@conf = YAML.load_file("bot_config.yaml")
@botname = @conf['botname']
@tmpdir = @conf['tmpdir']
token = @conf['token']
admin = @conf['admin']
@auth_chat = @conf['authorized_chats']
@allowed_sources = @conf['allowed_sources']

### Begin sanity check ###
STDOUT.sync = true
errcount = 0
puts "Checking if environment is sane...\n\n"
print "Checking bot token ...................... "
if token.nil?
    print "FAIL!\n\n".red.bold
    puts "No bot token defined in bot_config.yaml!\n" + "THIS IS REQUIRED!".red.bold + " Bot initialization failed; exiting..."
    exit(1)
else
    print "OK\n".green.bold
end
print "Checking configured bot name ............ "
if @botname.nil?
    errcount += 1
    print "FAIL!\n\n".red.bold
    puts "Error(#{errcount.to_s}): No bot name defined. This is superficial. We'll call him Bob.\n\n"
    @botname = "Bob"
else
    print "OK\n".green.bold
end
### Temporary directory check
print "Checking configured tmp directory ....... "
def is_tmp_writable?
    system("mkdir -p #{@tmpdir} >/dev/null 2>&1")
    if system("touch #{@tmpdir}/test.file >/dev/null 2>&1")
        system("rm #{@tmpdir}/test.file >/dev/null 2>&1")
        return true
    else
        system("rm #{@tmpdir}/test.file >/dev/null 2>&1") #Attempt to clean up anyway
        return false
    end
end

if @tmpdir.nil?
    errcount += 1
    print "FAIL!\n\n".red.bold
    puts "Error(#{errcount.to_s}): No temporary directory defined. Using '/tmp/.skyfall/egs-bot'.\n"
    @tmpdir = "/tmp/.skyfall/egs-bot"
    if is_tmp_writable?
        puts "Default temporary directory is writable. Continuing...\n\n"
    else
        errcount += 1
        puts "Error(#{errcount.to_s}): Temporary directory [" + @tmpdir.red.bold + "] is not writable!\n" + "THIS IS REQUIRED!".red.bold + " Bot initialization failed; exiting..."
        exit(1)
    end
else
    if is_tmp_writable?
        print "OK\n".green.bold
    else
        errcount += 1
        print "FAIL!\n\n".red.bold
        puts "Error(#{errcount.to_s}): Temporary directory [" + @tmpdir.red.bold + "] is not writable!\n" + "THIS IS REQUIRED!".red.bold + " Bot initialization failed; exiting..."
        exit(1)
    end
end
### End tmpdir check
print "Checking administrators ................. "
if admin.nil?
    errcount += 1
    print "FAIL!\n\n".red.bold
    puts "Error(#{errcount.to_s}): No admin Telegram IDs provided in bot_config.yaml.\nThis is required for many functions.\n" +
            "THIS SHOULD BE ADDRESSED. Continuing. (some commands will not be available)\n\n"
    admin = ["0"]
else
    print "OK\n".green.bold
end
print "Checking authorized chats ............... "
if @auth_chat.nil?
    errcount += 1
    print "FAIL!\n\n".red.bold
    puts "Error(#{errcount.to_s}): No authorized Telegram group IDs provided in bot_config.yaml.\nThis is required for most Empyrion-related " +
            "functions.\nTHIS SHOULD BE ADDRESSED. Continuing. (some commands will not be available)\n\n"
    @auth_chat = ["0"]
else
    print "OK\n".green.bold
end
puts "Errors found: #{errcount.to_s}\n\n"
if errcount > 0
    print "Environment is grinning and holding a spatula. Please review your configuration.\n\n".red.bold
else
    print "Environment appears sane.\n\n".green.bold
end
STDOUT.sync = false
### End sanity check ###
puts "Starting [#{@botname}]...\n\n"
puts "Authorized administrator IDs: #{admin}"
puts "Authorized chat IDs: #{@auth_chat}"
puts "Bot token: #{token}"
puts "Temporary direcotry: #{@tmpdir}"
puts "Start time: " + timestamp + "\n\n\n\n"
STDOUT.flush

def handle_message(message)
    if ! message.reply_to_message.nil? then
        #drop message. Someone's replying to a message
        #sent by our bot
        message.text = nil
        return
    end

    if message.text.nil?
        # Find out if user(s) joined the group. If so, welcome them
        #if ! message.new_chat_members.nil?
        #    handle_user_join(message)
        #else
        #    #Handle non-messages and non-joins here
        #end
        return #so that we don't try to process this as a command (below)
    end

    #Format sender name
    if ! message.from.username.nil?
        message.from.username = "@" + message.from.username
    elsif ! message.from.first_name.nil?
        message.from.username = message.from.first_name
    end

    #Format command
    command = message.text.split(" ")[0].split("@")[0].downcase #Strip command from arguments and @tags

    reply = 'Empty String'
    adm = @conf['admin']
    puts Time.now.strftime("%F %H:%M:%S").yellow + ": Received command from " + "#{message.from.username}".cyan.bold + " [" + "#{message.from.id}".cyan + "]: " + "#{command}".magenta.bold
    case command
        when '/start'
            reply = "I am #{@botname}, and I am here to provide temperature information from various sensors. Currently I can retrieve information " +
                    "from temperature sensors as well as report when temperatures are out of a specified range.\n\n" +
                    "Commands available:\n/start (Shows this message)\n/check (Show temperatures, currently non-functional)\n/whoami or /chatinfo (Provides IDs for internal use)\n/whereareyou or /location (Provides hostname for bot server)\n\n" +
                    "Check again later to see if any new functions have been added, or use /patchnotes to learn about recent updates.\n" +
                    "You can also view the source code at the following location:\nhttps://git.skyfall.tech/skyfall/heatbot"
            if message_from_admin?(message, adm)
                msg_from_admin = true
            end
            if is_chat_authorized?(message, @auth_chat)
                chat_authorized = true
            end
            if ! msg_from_admin && ! chat_authorized
                if message.from.id == message.chat.id
                    reply = reply + "\n\nWARNING: I am not authorized to work with you directly. My functionality is limited."
                else
                    reply = reply + "\n\nWARNING: I am not authorized to participate with this group. My functionality is limited."
                end
            elsif msg_from_admin && ! chat_authorized
                reply = reply + "\n\nWARNING: Although you are an administrator, I have not been authorized to participate in this group. My functionality is limited."
            end
        when '/patch', '/patchnotes'
            reply = process_command_patchnotes(message, command, adm)
        when '/location', '/whereareyou'
            if message_from_admin?(message, adm) || is_chat_authorized?(message, @auth_chat)
                reply = "I am currently located at:\n\nHost: #{`head -n1 /etc/hostname`}ExtIP: #{`curl icanhazip.com 2>/dev/null`}"
            else
                reply = "I am not authorized to provide this information here."
            end
        when '/whoami', '/chatinfo'
            reply = "User ID: #{message.from.id}\nChat ID: #{message.chat.id}"
        when '/check'
            reply = process_command_check(message, command, adm)
        when '/pp', '/debug'
            pp message
            reply = "Confirmation: Message debug information sent to console."
        else
            reply = "Sorry, #{command} is not a valid command."
    end
    # Verbose output:
    puts timestamp + ": Sending #{reply.inspect}\n\n"
    STDOUT.flush
    return reply
end

Telegram::Bot::Client.run(token) do |bot|
    bot.listen do |message|
        #pp message
        validation = validate_incoming_data(message)
        #puts "DEBUG: #{validation}"
        if validation
            reply = handle_message(message)
            if ! message.text.nil?
                bot.api.send_message(chat_id: message.chat.id, text: "#{reply}")
            end
            STDOUT.flush
        else
            puts "Received bad data! [#{message.chat.type}]"
            puts validation
            STDOUT.flush
        end
    end
end