#!/usr/bin/env bash
#
# collider.jam boot shell script
#
# Following steps are performed if needed:
#    * check all necessary prerequisites (node, npm)
#    * generate initial package.json
#    * install collider.jam shell
#    * run jam shell
#

# save command line
CMD_LINE=$@

# env
NODE="node"
NPM="npm"

JAM="jam"
JAM_MODULE="collider.jam"

BOOT_MODULE="collider-boot.mix"

# error codes
ERROR_NO_NODEJS=1
ERROR_INIT_FIRST=2
ERROR_PACKAGE_EXISTS=3
ERROR_NO_SHELL=4
ERROR_ALREADY_GENERATED=5

# === flags ===

# check node.js 
NODE_FLAG=1
type "$NODE" >/dev/null 2>&1 || { unset NODE_FLAG; }
# check npm 
NPM_FLAG=1
type "$NPM" >/dev/null 2>&1 || { unset NPM_FLAG; }
# check global collider.jam installation
GLOBAL_JAM_FLAG=1
type "$JAM" >/dev/null 2>&1 || { unset GLOBAL_JAM_FLAG; }

update_flags() {
    # check package.json
    if [ -f ./package.json ]; then
        PACKAGE_FLAG=1
    fi
    # check node modules
    if [ -d ./node_modules ]; then
        MODULES_FLAG=1
    fi
    # check local collider.jam shell
    if [ -d ./node_modules/$JAM_MODULE ]; then
        JAM_PACKAGE_FLAG=1
    fi
    if [ -f ./node_modules/$JAM_MODULE/jam.js ]; then
        JAM_SHELL_FLAG=1
    fi
    # check collider.jam
    if [ -d ./node_modules/$COLLIDER ]; then
        COLLIDER_FLAG=1
    fi
}

help() {
    echo '=== Welcome to collider.jam boot script! ==='
    echo ''
    echo 'Usage: ./jam'
    echo '       ./jam <command>'
    echo '       ./jam <command> <arguments...>'
    echo ''
    echo 'Available options are:'
    echo '    init <bootstrap-template> - generate project using provided template'
    echo '    install - install collider.jam shell globally'
    echo ''
    echo 'All other commands are routed to collider.jam shell when installed'
}

check_status() {
    LAST=$?

    if [ $LAST -ne 0 ]; then
        echo "A problem occured during the execution (error #$LAST)"
        exit $LAST
    fi
}

install() {
    echo 'Installing collider.jam shell globaly'
    #$NPM install -g git+$JAM_REPO
    $NPM install -g $JAM_REPO
    check_status
}

init() {
    NAME=$1

    # check that no package.json present before generating a new one
    if [[ $PACKAGE_FLAG ]]; then
        echo "Error: package.json is already exists!"
        echo "Can't init the project [$NAME]"
        exit $ERROR_PACKAGE_EXISTS
    fi

    echo "Generating project [$NAME]"

    echo -n 'Generating package.json...'
    echo -e "{
      \"name\": \"$NAME\",
      \"version\": \"0.0.1\",
      \"description\": \"collider.jam game project\",
      \"keywords\": \"collider,jam,mod,game engine,game framework,game jam\",
      \"scripts\": {
          \"start\": \"node ./node_modules/$JAM_MODULE/jam.js\"
      },
      \"dependencies\": {
          \"$JAM_MODULE\": \"https://github.com/invider/collider.jam.git\",
          \"collider.mix\": \"https://github.com/invider/collider.mix.git\",
          \"collider-boot.mix\": \"https://github.com/invider/collider-boot.mix.git\",
          \"collider-dev.mix\": \"https://github.com/invider/collider-dev.mix.git\"
      },
      \"author\": \"\",
      \"license\": \"MIT\"\n}" > package.json

    echo 'Installing dependencies...'
    $NPM install
    echo `du -sh ./node_modules | cut -f 1`' of modules installed'
    update_flags

    bootstrap
}

bootstrap() {
    # trim 'init' command from params
    CMD_LINE=${CMD_LINE:4}

    node ./node_modules/$JAM_MODULE/jam.js bootstrap $CMD_LINE
    check_status

    echo ''
    echo '=== The project is ready! ==='
    echo ''
    echo "Type ./jam play"
    echo '   or'
    echo 'Type ./jam and then open http://localhost:9999 in browser'
}

cmd() {
    update_flags
    if [[ ! $JAM_SHELL_FLAG ]]; then
        echo 'No collider.jam shell installed!'
        exit $ERROR_NO_SHELL
    fi

    if [[ $1 = "init" ]]; then
        echo 'it looks like the project is already generated!'
        exit $ERROR_ALREADY_GENERATED

    else
        node ./node_modules/$JAM_MODULE/jam.js $CMD_LINE

    fi
}

update_flags

if [[ ! $NODE_FLAG || ! $NPM_FLAG ]]; then
    echo 'No Node.js found!'
    echo 'You must install Node.js in order to use collider.jam shell!'
    exit $ERROR_NO_NODEJS
fi

# generic commands always working from bootstrap script
if [[ $1 = "install" ]]; then
    install
fi

    
if [[ ! $PACKAGE_FLAG ]]; then
    echo 'No collider.jam project detected!'

    if [[ $1 = "init" ]]; then
        NAME="${PWD##*/}"
        init $NAME

    elif [[ $1 = "help" ]]; then
        help

    else
        echo 'You must init the project first'
        echo 'Try ./jam init'
        exit $ERROR_INIT_FIRST
    fi

else

    if [[ ! $MODULES_FLAG || ! $JAM_PACKAGE_FLAG ]]; then
        echo '[jam-starter] Modules missing!'
        echo '[jam-starter] Installing dependencies... '
        $NPM update
        check_status
    fi

    if [[ ! $GLOBAL_JAM_FLAG ]]; then
        echo "[jam-starter] no global collider.jam installation found!"
        echo "[jam-starter] to install, type ./jam install"
    fi

    cmd $1
fi