#!/bin/bash

command=$1
config=$2
config_file=containers/"$config".yml
cidfile=cids/"$config".cid
cidbootstrap=cids/"$config"_boostrap.cid
local_discourse=local_discourse
image=samsaffron/discourse
docker_path=`which docker`

docker_ip=`/sbin/ifconfig | \
                grep -B1 "inet addr" | \
                awk '{ if ( $1 == "inet" ) { print $2 } else if ( $2 == "Link" ) { printf "%s:" ,$1 } }' | \
                grep docker0 | \
                awk -F: '{ print $3 }';`


usage () {
  echo "Usage: launcher COMMAND CONFIG"
  echo "Commands:"
  echo "    start:      Start/initialize a container"
  echo "    stop:       Stop a running container"
  echo "    restart:    Restart a container"
  echo "    destroy:    Stop and remove a container"
  echo "    ssh:        Start a bash shell in a running container"
  echo "    logs:       Docker logs for container"
  echo "    bootstrap:  Bootstrap a container for the config based on a template"
  exit 1
}

install_docker() {

  echo "Docker is not installed, make sure you are running on the 3.8 kernel"
  echo "The best supported Docker release is Ubuntu 12.04.03 for it run the following"
  echo
  echo "sudo apt-get update"
  echo "sudo apt-get install linux-image-generic-lts-raring linux-headers-generic-lts-raring"
  echo "sudo reboot"
  echo

  echo "sudo sh -c \"wget -qO- https://get.docker.io/gpg | apt-key add -\""
  echo "sudo sh -c \"echo deb http://get.docker.io/ubuntu docker main > /etc/apt/sources.list.d/docker.list\""
  echo "sudo apt-get update"
  echo "sudo apt-get install lxc-docker"

  exit 1
}

set_volumes() {
  volumes=`cat $config_file | docker run -rm -i -a stdout -a stdin $image ruby -e \
        "require 'yaml'; puts YAML.load(STDIN.readlines.join)['volumes'].map{|v| '-v ' << v['volume']['host'] << ':' << v['volume']['guest'] << ' '}.join"`
}

set_template_info() {

    templates=`cat $config_file | docker run -rm -i -a stdin -a stdout $image ruby -e \
      "require 'yaml'; puts YAML.load(STDIN.readlines.join)['templates']"`


    arrTemplates=(${templates// / })
    config_data=$(cat $config_file)

    input="hack: true"


    for template in "${arrTemplates[@]}"
    do
      [ ! -z $template ] && {
        input="$input _FILE_SEPERATOR_ $(cat $template)"
      }
    done

    # we always want our config file last so it takes priority
    input="$input _FILE_SEPERATOR_ $config_data"

    read -r -d '' env_ruby << 'RUBY'
    require 'yaml'

    input=STDIN.readlines.join
    env = {}
    input.split('_FILE_SEPERATOR_').each do |yml|
       yml.strip!
       begin
         env.merge!(YAML.load(yml)['env'] || {})
       rescue => e
        puts yml
        p e
       end
    end
    puts env.map{|k,v| "-e\n#{k}=#{v}" }.join("\n")
RUBY

    raw=`exec echo "$input" | docker run -rm -i -a stdin -a stdout $image ruby -e "$env_ruby"`

    env=()
    while read i; do
      env[${#env[@]}]=$i
    done <<< "$raw"

    echo "Calculated ENV: ${env[@]}"
}

[ -z $docker_path ] && {
  install_docker
}


[ $# -ne 2 ] && {
  usage
}

if [ ! -e $config_file ]
  then
    echo "Config file was not found, ensure $config_file exists"
    exit 1
fi

case "$command" in
  bootstrap)

      set_template_info

      base_image=`cat $config_file | docker run -rm -i -a stdin -a stdout $image ruby -e \
        "require 'yaml'; puts YAML.load(STDIN.readlines.join)['base_image']"`

      update_pups=`cat $config_file | docker run -rm -i -a stdin -a stdout $image ruby -e \
        "require 'yaml'; puts YAML.load(STDIN.readlines.join)['update_pups']"`

      if [[ ! X"" = X"$base_image" ]]; then
        image=$base_image
      fi

      set_volumes

      rm -f $cidbootstrap

      run_command="cd /pups &&"
      if [[ ! "false" =  $update_pups ]]; then
        run_command="$run_command git pull &&"
      fi
      run_command="$run_command /pups/bin/pups --stdin"

      (exec echo "$input" | docker run "${env[@]}" -e DOCKER_HOST_IP=$docker_ip -cidfile $cidbootstrap -i -a stdin -a stdout -a stderr $volumes $image \
         /bin/bash -c "$run_command") \
         || (docker rm `cat $cidbootstrap` && rm $cidbootstrap)

      [ ! -e $cidbootstrap ] && echo "FAILED TO BOOTSTRAP" && exit 1

      sleep 5

      docker commit `cat $cidbootstrap` $local_discourse/$config || echo 'FAILED TO COMMIT'
      docker rm `cat $cidbootstrap` && rm $cidbootstrap

      echo "Successfully bootstrapped, to startup use ./launcher start $config"
      exit 0
      ;;

  ssh)
      if [ ! -e $cidfile ]
         then
           echo "No cid found"
           exit 1
         else
           cid="`cat $cidfile`"
           address="`docker port $cid 22`"
           split=(${address//:/ })
           exec ssh root@${split[0]} -p ${split[1]}
      fi
      ;;

  stop)
      if [ ! -e $cidfile ]
         then
           echo "No cid found"
           exit 1
         else
           docker stop -t 10 `cat $cidfile`
           exit 0
      fi
      ;;

  logs)

      if [ ! -e $cidfile ]
         then
           echo "No cid found"
           exit 1
         else
           docker logs `cat $cidfile`
           exit 0
      fi
      ;;

  start)

      if [ ! -e $cidfile ]
         then
           echo "No cid found, creating a new container"
           ports=`cat $config_file | docker run -rm -i -a stdout -a stdin $image ruby -e \
                  "require 'yaml'; puts YAML.load(STDIN.readlines.join)['expose'].map{|p| '-p ' << p.to_s << ' '}.join"`

           set_template_info
           set_volumes

           existing=`docker ps -a | awk '{ print $1, $(NF) }' | grep "$config$" | awk '{ print $1 }'`
           if [ ! -z $existing ]
           then
             echo "Found an existing container by its name, recovering cidfile, please rerun"
             echo $existing > $cidfile
             exit 1
           fi

           docker run "${env[@]}" -e DOCKER_HOST_IP=$docker_ip -name $config -cidfile $cidfile $ports \
                      -d $volumes $local_discourse/$config /usr/bin/runsvdir -P /etc/service

           exit 0
         else
           cid=`cat $cidfile`

           if [ -z $cid ]
           then
             echo "Detected empty cid file, deleting, please re-run"
             rm $cidfile
             exit 1
           fi

           found=`docker ps -q -a -notrunc | grep $cid`
           if [ -z $found ]
           then
             echo "Invalid cid file, deleting, please re-run"
             rm $cidfile
             exit 1
           fi

           echo "cid found, ensuring container is started"
           docker start `cat $cidfile`
           exit 0
      fi
      ;;


  destroy)
      if [ -e $cidfile ]
        then
          echo "destroying container $cidfile"
          docker stop -t 10 `cat $cidfile`
          docker rm `cat $cidfile` && rm $cidfile
          exit 0
        else
          echo "nothing to destroy cidfile does not exist"
          exit 1
      fi
      ;;
esac

usage