# Copyright 2014 OpenStack Foundation
# Copyright 2014 Hewlett-Packard Development Company, L.P.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

import argparse
import logging
import os
import sys
import threading
import webbrowser

import urwid

from gertty import db
from gertty import config
from gertty import gitrepo
from gertty import mywid
from gertty import sync
from gertty.view import change_list as view_change_list
from gertty.view import project_list as view_project_list
from gertty.view import change as view_change
import gertty.view

WELCOME_TEXT = """\
Welcome to Gertty!

To get started, you should subscribe to some projects.  Press the "l"
key to list all the projects, navigate to the ones you are interested
in, and then press "s" to subscribe to them.  Gertty will
automatically sync changes in your subscribed projects.

Press the F1 key anywhere to get help.  Your terminal emulator may
require you to press function-F1 or alt-F1 instead.

"""

class StatusHeader(urwid.WidgetWrap):
    def __init__(self, app):
        super(StatusHeader, self).__init__(urwid.Columns([]))
        self.app = app
        self.title = urwid.Text(u'Start')
        self.error = urwid.Text('')
        self.offline = urwid.Text('')
        self.sync = urwid.Text(u'Sync: 0')
        self._w.contents.append((self.title, ('pack', None, False)))
        self._w.contents.append((urwid.Text(u''), ('weight', 1, False)))
        self._w.contents.append((self.error, ('pack', None, False)))
        self._w.contents.append((self.offline, ('pack', None, False)))
        self._w.contents.append((self.sync, ('pack', None, False)))

    def update(self, title=None, error=False, offline=None):
        if title:
            self.title.set_text(title)
        if error:
            self.error.set_text(('error', u'Error'))
        if offline is not None:
            if offline:
                self.error.set_text(u'Offline')
            else:
                self.error.set_text(u'')
        self.sync.set_text(u' Sync: %i' % self.app.sync.queue.qsize())

class SearchDialog(mywid.ButtonDialog):
    signals = ['search', 'cancel']
    def __init__(self):
        search_button = mywid.FixedButton('Search')
        cancel_button = mywid.FixedButton('Cancel')
        urwid.connect_signal(search_button, 'click',
                             lambda button:self._emit('search'))
        urwid.connect_signal(cancel_button, 'click',
                             lambda button:self._emit('cancel'))
        super(SearchDialog, self).__init__("Search",
                                           "Enter a change number or search string.",
                                           entry_prompt="Search: ",
                                           buttons=[search_button,
                                                    cancel_button])

    def keypress(self, size, key):
        r = super(SearchDialog, self).keypress(size, key)
        if r == 'enter':
            self._emit('search')
            return None
        return r

class App(object):
    def __init__(self, server=None, palette='default', debug=False, disable_sync=False):
        self.server = server
        self.config = config.Config(server, palette)
        if debug:
            level = logging.DEBUG
        else:
            level = logging.WARNING
        logging.basicConfig(filename=self.config.log_file, filemode='w',
                            format='%(asctime)s %(message)s',
                            level=level)
        self.log = logging.getLogger('gertty.App')
        self.log.debug("Starting")
        self.db = db.Database(self)
        self.sync = sync.Sync(self)

        self.screens = []
        self.status = StatusHeader(self)
        self.header = urwid.AttrMap(self.status, 'header')
        screen = view_project_list.ProjectListView(self)
        self.status.update(title=screen.title)
        self.loop = urwid.MainLoop(screen, palette=self.config.palette.getPalette(),
                                   unhandled_input=self.unhandledInput)
        if screen.isEmpty():
            self.welcome()
        self.sync_pipe = self.loop.watch_pipe(self.refresh)
        self.loop.screen.tty_signal_keys(start='undefined', stop='undefined')
        #self.loop.screen.set_terminal_properties(colors=88)
        if not disable_sync:
            self.sync_thread = threading.Thread(target=self.sync.run, args=(self.sync_pipe,))
            self.sync_thread.daemon = True
            self.sync_thread.start()
        else:
            self.sync_thread = None
            self.sync.offline = True
            self.status.update(offline=True)

    def run(self):
        self.loop.run()

    def _quit(self, widget=None):
        raise urwid.ExitMainLoop()

    def quit(self):
        dialog = mywid.YesNoDialog(u'Quit',
                                   u'Are you sure you want to quit?')
        urwid.connect_signal(dialog, 'no', self.backScreen)
        urwid.connect_signal(dialog, 'yes', self._quit)

        self.popup(dialog)

    def changeScreen(self, widget):
        self.log.debug("Changing screen to %s" % (widget,))
        self.status.update(title=widget.title)
        self.screens.append(self.loop.widget)
        self.loop.widget = widget

    def backScreen(self, widget=None):
        if not self.screens:
            return
        widget = self.screens.pop()
        self.log.debug("Popping screen to %s" % (widget,))
        if hasattr(widget, 'title'):
            self.status.update(title=widget.title)
        self.loop.widget = widget
        self.refresh()

    def clearHistory(self):
        self.log.debug("Clearing screen history")
        while self.screens:
            widget = self.screens.pop()
            self.loop.widget = widget

    def refresh(self, data=None):
        widget = self.loop.widget
        while isinstance(widget, urwid.Overlay):
            widget = widget.contents[0][0]
        widget.refresh()

    def popup(self, widget,
              relative_width=50, relative_height=25,
              min_width=20, min_height=8):
        overlay = urwid.Overlay(widget, self.loop.widget,
                                'center', ('relative', relative_width),
                                'middle', ('relative', relative_height),
                                min_width=min_width, min_height=min_height)
        self.log.debug("Overlaying %s on screen %s" % (widget, self.loop.widget))
        self.screens.append(self.loop.widget)
        self.loop.widget = overlay

    def help(self):
        if not hasattr(self.loop.widget, 'help'):
            return
        text = mywid.GLOBAL_HELP
        for d in self.config.dashboards.values():
            space = max(9 - len(d['key']), 0) * ' '
            text += '<%s>%s %s\n' % (d['key'], space, d['name'])
        text += "\nThis Screen\n"
        text += "===========\n"
        text += self.loop.widget.help()
        dialog = mywid.MessageDialog('Help', text)
        lines = text.split('\n')
        urwid.connect_signal(dialog, 'close',
            lambda button: self.backScreen())
        self.popup(dialog, min_width=76, min_height=len(lines)+4)

    def welcome(self):
        text = WELCOME_TEXT + self.loop.widget.help
        dialog = mywid.MessageDialog('Welcome', text)
        lines = text.split('\n')
        urwid.connect_signal(dialog, 'close',
            lambda button: self.backScreen())
        self.popup(dialog, min_width=76, min_height=len(lines)+4)

    def _syncOneChangeFromQuery(self, query):
        number = changeid = None
        if query.startswith("number:"):
            number = query.split(':')[1].strip()
            try:
                number = int(number)
            except Exception:
                pass
        if query.startswith("changeid:"):
            changeid = query.split(':')[1].strip()
        if not (number or changeid):
            return
        with self.db.getSession() as session:
            if number:
                change = session.getChangeByNumber(number)
            elif changeid:
                change = session.getChangeByChangeID(changeid)
            change_key = change and change.key or None
        if change_key is None:
            if self.sync.offline:
                raise Exception('Can not sync change while offline.')
            task = sync.SyncChangeByNumberTask(number, sync.HIGH_PRIORITY)
            self.sync.submitTask(task)
            succeeded = task.wait(300)
            if not succeeded:
                raise Exception('Unable to find change.')
            for subtask in task.tasks:
                succeeded = task.wait(300)
                if not succeeded:
                    raise Exception('Unable to sync change.')
            with self.db.getSession() as session:
                change = session.getChangeByNumber(number)
                change_key = change and change.key or None
        if change_key is None:
            raise Exception('Change is not in local database.')

    def search(self, query):
        self.log.debug("Search query: %s" % query)
        try:
            self._syncOneChangeFromQuery(query)
        except Exception as e:
            return self.error(e.message)
        with self.db.getSession() as session:
            changes = session.getChanges(query)
            change_key = None
            if len(changes) == 1:
                change_key = changes[0].key
        try:
            if change_key:
                view = view_change.ChangeView(self, change_key)
            else:
                view = view_change_list.ChangeListView(self, query)
            self.changeScreen(view)
        except gertty.view.DisplayError as e:
            self.error(e.message)

    def searchDialog(self):
        dialog = SearchDialog()
        urwid.connect_signal(dialog, 'cancel',
            lambda button: self.backScreen())
        urwid.connect_signal(dialog, 'search',
            lambda button: self._searchDialog(dialog))
        self.popup(dialog, min_width=76, min_height=8)

    def _searchDialog(self, dialog):
        self.backScreen()
        query = dialog.entry.edit_text
        try:
            query = 'number:%s' % int(query)
        except Exception:
            pass
        self.search(query)

    def error(self, message):
        dialog = mywid.MessageDialog('Error', message)
        urwid.connect_signal(dialog, 'close',
                             lambda button: self.backScreen())
        self.popup(dialog, min_height=4)
        return None

    def unhandledInput(self, key):
        if key == 'esc':
            self.backScreen()
        elif key == 'f1' or key == '?':
            self.help()
        elif key == 'ctrl q':
            self.quit()
        elif key == 'ctrl o':
            self.searchDialog()
        elif key in self.config.dashboards:
            d = self.config.dashboards[key]
            self.clearHistory()
            view = view_change_list.ChangeListView(self, d['query'], d['name'])
            self.changeScreen(view)

    def getRepo(self, project_name):
        local_path = os.path.join(self.config.git_root, project_name)
        local_root = os.path.abspath(self.config.git_root)
        assert os.path.commonprefix((local_root, local_path)) == local_root
        return gitrepo.Repo(self.config.url+'p/'+project_name,
                            local_path)

    def openURL(self, url):
        self.log.debug("Open URL %s" % url)
        webbrowser.open_new_tab(url)

def main():
    parser = argparse.ArgumentParser(
        description='Console client for Gerrit Code Review.')
    parser.add_argument('-d', dest='debug', action='store_true',
                        help='enable debug logging')
    parser.add_argument('--no-sync', dest='no_sync', action='store_true',
                        help='disable remote syncing')
    parser.add_argument('-p', dest='palette', default='default',
                        help='Color palette to use')
    parser.add_argument('server', nargs='?',
                        help='the server to use (as specified in config file)')
    args = parser.parse_args()
    g = App(args.server, args.palette, args.debug, args.no_sync)
    g.run()


if __name__ == '__main__':
    main()