#!/usr/local/bin/python2.7
# -*- mode: Python; indent-tabs-mode: nil; -*-

import os
import re
import socket
import subprocess
import sys
import optparse
import tempfile
try:
    import json
except ImportError:
    try:
        import simplejson as json
    except ImportError:
        print 'The Python simplejson module is required'
        sys.exit(1)

from gi.repository import Gio

SAMPLE_EXTENSION_FILES = {
    "extension.js": """
const St = imports.gi.St;
const Main = imports.ui.main;
const Tweener = imports.ui.tweener;

let text, button;

function _hideHello() {
    Main.uiGroup.remove_actor(text);
    text = null;
}

function _showHello() {
    if (!text) {
        text = new St.Label({ style_class: 'helloworld-label', text: "Hello, world!" });
        Main.uiGroup.add_actor(text);
    }

    text.opacity = 255;

    let monitor = Main.layoutManager.primaryMonitor;

    text.set_position(monitor.x + Math.floor(monitor.width / 2 - text.width / 2),
                      monitor.y + Math.floor(monitor.height / 2 - text.height / 2));

    Tweener.addTween(text,
                     { opacity: 0,
                       time: 2,
                       transition: 'easeOutQuad',
                       onComplete: _hideHello });
}

function init() {
    button = new St.Bin({ style_class: 'panel-button',
                          reactive: true,
                          can_focus: true,
                          x_fill: true,
                          y_fill: false,
                          track_hover: true });
    let icon = new St.Icon({ icon_name: 'system-run-symbolic',
                             style_class: 'system-status-icon' });

    button.set_child(icon);
    button.connect('button-press-event', _showHello);
}

function enable() {
    Main.panel._rightBox.insert_child_at_index(button, 0);
}

function disable() {
    Main.panel._rightBox.remove_child(button);
}
""",

    "stylesheet.css": """
.helloworld-label {
    font-size: 36px;
    font-weight: bold;
    color: #ffffff;
    background-color: rgba(10,10,10,0.7);
    border-radius: 5px;
    padding: .5em;
}
""",
}

def create_extension():
    print
    print '''Name should be a very short (ideally descriptive) string.
Examples are: "Click To Focus",  "Adblock", "Shell Window Shrinker".
'''
    name = raw_input('Name: ').strip()
    print
    print '''Description is a single-sentence explanation of what your extension does.
Examples are: "Make windows visible on click", "Block advertisement popups"
              "Animate windows shrinking on minimize"
'''
    description = raw_input('Description: ').strip()
    underifier = re.compile('[^A-Za-z]')
    sample_uuid = underifier.sub('_', name)
    # TODO use evolution data server
    hostname = socket.gethostname()
    sample_uuid = sample_uuid + '@' + hostname

    print
    print '''Uuid is a globally-unique identifier for your extension.
This should be in the format of an email address (foo.bar@extensions.example.com), but
need not be an actual email address, though it's a good idea to base the uuid on your
email address.  For example, if your email address is janedoe@example.com, you might
use an extension title clicktofocus@janedoe.example.com.'''
    uuid = raw_input('Uuid [%s]: ' % (sample_uuid, )).strip()
    if uuid == '':
        uuid = sample_uuid

    extension_path = os.path.join(os.path.expanduser('~/.local'), 'share', 'gnome-shell', 'extensions', uuid)
    if os.path.exists(extension_path):
        print "Extension path %r already exists" % (extension_path, )
        sys.exit(0)
    os.makedirs(extension_path)
    meta = { 'name': name,
             'description': description,
             'uuid': uuid,
             'shell-version': ['3.14.3'] }
    f = open(os.path.join(extension_path, 'metadata.json'), 'w')
    try:
        json.dump(meta, f)
    except AttributeError:
        # For Python versions older than 2.6, try using the json-py module
        f.write(json.write(meta) + '\n')
    f.close()

    for filename, contents in SAMPLE_EXTENSION_FILES.iteritems():
        path = os.path.join(extension_path, filename)
        f = open(path, 'w')
        f.write(contents)
        f.close()

    print "Created extension in %r" % (extension_path, )
    extensionjs_path = os.path.join(extension_path, 'extension.js')
    subprocess.Popen(['xdg-open', extensionjs_path])

ENABLED_EXTENSIONS_KEY = 'enabled-extensions'

def enable_extension(uuid):
    settings = Gio.Settings(schema='org.gnome.shell')
    extensions = settings.get_strv(ENABLED_EXTENSIONS_KEY)

    if uuid in extensions:
        print >> sys.stderr, "%r is already enabled." % (uuid,)
        sys.exit(1)

    extensions.append(uuid)
    settings.set_strv(ENABLED_EXTENSIONS_KEY, extensions)
    print >> sys.stderr, "%r is now enabled." % (uuid,)

def disable_extension(uuid):
    settings = Gio.Settings(schema='org.gnome.shell')
    extensions = settings.get_strv(ENABLED_EXTENSIONS_KEY)

    if uuid not in extensions:
        print >> sys.stderr, "%r is not enabled or installed." % (uuid,)
        sys.exit(1)

    # Use a while loop here to remove *all* mentions instances
    # of the extension. Some faulty tools like to append more than one.
    while uuid in extensions:
        extensions.remove(uuid)

    settings.set_strv(ENABLED_EXTENSIONS_KEY, extensions)
    print >> sys.stderr, "%r is now disabled." % (uuid,)

def main():
    parser = optparse.OptionParser()
    parser.add_option("-d", "--disable-extension", dest="disable",
                      help="Disable a GNOME Shell extension")
    parser.add_option("-e", "--enable-extension", dest="enable",
                      help="Enable a GNOME Shell extension")
    parser.add_option("-c", "--create-extension", dest="create", action="store_true",
                      help="Create a new GNOME Shell extension")
    options, args = parser.parse_args()

    if args:
        parser.print_usage()
        sys.exit(1)

    if options.disable:
        disable_extension(options.disable)

    elif options.enable:
        enable_extension(options.enable)

    elif options.create:
        create_extension()

    else:
        parser.print_usage()
        sys.exit(1)

if __name__ == "__main__":
    main()
