# -*- coding: utf-8; mode: python; -*-
#
#  GStreamer Debug Viewer - View and analyze GStreamer debug log files
#
#  Copyright (C) 2007 René Stadler <mail@renestadler.de>
#
#  This program is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by the Free
#  Software Foundation; either version 3 of the License, or (at your option)
#  any later version.
#
#  This program is distributed in the hope that it will be useful, but WITHOUT
#  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
#  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
#  more details.
#
#  You should have received a copy of the GNU General Public License along with
#  this program.  If not, see <http://www.gnu.org/licenses/>.

"""GStreamer Debug Viewer timeline widget plugin."""

import logging

from GstDebugViewer import Common, Data, GUI
from GstDebugViewer.Plugins import *

import gtk

class SearchOperation (object):

    def __init__ (self, model, search_string, search_forward = True, start_position = None):

        self.model = model
        self.search_string = search_string
        self.search_forward = search_forward
        self.start_position = start_position

class SearchSentinel (object):

    def __init__ (self):

        self.dispatcher = Common.Data.GSourceDispatcher ()

    def run_for (self, operation):

        self.dispatcher.cancel ()
        self.dispatcher (self.__process (operation))

    def abort (self):

        self.dispatcher.cancel ()

    def __process (self, operation):

        model = operation.model

        if operation.start_position is not None:
            start_iter = model.iter_nth_child (None, operation.start_position)
        else:
            start_iter = model.iter_nth_child (None, 0)

        if not operation.search_forward:
            # FIXME:
            raise NotImplementedError ("backward search not supported yet")

        search_string = operation.search_string
        col_id = model.COL_MESSAGE
        model_get = model.get_value
        iter_next = model.iter_next

        YIELD_LIMIT = 1000
        i = YIELD_LIMIT
        tree_iter = start_iter
        while tree_iter:
            i -= 1
            if i == 0:
                yield True
                i = YIELD_LIMIT
            msg = model_get (tree_iter, col_id)
            if search_string in msg:
                self.handle_match_found (model, tree_iter)
            tree_iter = iter_next (tree_iter)

        self.handle_search_complete ()
        yield False

    def handle_match_found (self, model, tree_iter):

        pass

    def handle_search_complete (self):

        pass

class FindBarWidget (gtk.HBox):

    def __init__ (self):

        gtk.HBox.__init__ (self)

        label = gtk.Label (_("Find:"))
        self.pack_start (label, False, False, 0)

        self.entry = gtk.Entry ()
        self.pack_start (self.entry)

        self.show_all ()

class FindBarFeature (FeatureBase):

    def __init__ (self):

        FeatureBase.__init__ (self)

        self.matches = []

        self.logger = logging.getLogger ("ui.findbar")

        self.action_group = gtk.ActionGroup ("FindBarActions")
        self.action_group.add_toggle_actions ([("show-find-bar",
                                                None,
                                                _("Find Bar"),
                                                "<Ctrl>F")])

        self.bar = None
        self.operation = None

        self.sentinel = SearchSentinel ()
        self.sentinel.handle_match_found = self.handle_match_found
        self.sentinel.handle_search_complete = self.handle_search_complete

    def scroll_view_to_line (self, line_index):

        view = self.log_view

        path = (line_index,)

        start_path, end_path = view.get_visible_range ()

        if path >= start_path and path <= end_path:
            self.logger.debug ("line index %i already visible, not scrolling", line_index)
            return

        self.logger.debug ("scrolling to line_index %i", line_index)
        view.scroll_to_cell (path, use_align = True, row_align = .5)

    def handle_attach_window (self, window):

        ui = window.ui_manager

        ui.insert_action_group (self.action_group, 0)

        self.log_view = window.log_view
        
        self.merge_id = ui.new_merge_id ()
        ui.add_ui (self.merge_id, "/menubar/ViewMenu/ViewMenuAdditions",
                   "ViewFindBar", "show-find-bar",
                   gtk.UI_MANAGER_MENUITEM, False)

        box = window.widgets.vbox_view
        self.bar = FindBarWidget ()
        box.pack_end (self.bar, False, False, 0)
        self.bar.hide ()

        action = self.action_group.get_action ("show-find-bar")
        handler = self.handle_show_find_bar_action_activate
        action.connect ("toggled", handler)

        self.bar.entry.connect ("changed", self.handle_entry_changed)

    def handle_detach_window (self, window):

        window.ui_manager.remove_ui (self.merge_id)
        self.merge_id = None

    def handle_show_find_bar_action_activate (self, action):

        if action.props.active:
            self.bar.show ()
            self.bar.entry.grab_focus ()
        else:
            self.bar.hide ()

    def handle_entry_changed (self, entry):

        # FIXME: If the new search operation is stricter than the previous one
        # (find as you type!), re-use the previous results for a nice
        # performance gain (by only searching in previous results again)
        del self.matches[:]

        model = self.log_view.props.model
        search_string = entry.props.text
        if search_string == "":
            self.logger.debug ("search string set to '', aborting search")
            self.sentinel.abort ()
        # FIXME: Set start position
        self.logger.debug ("starting search for %r", search_string)
        self.operation = SearchOperation (model, search_string)
        self.sentinel.run_for (self.operation)

    def handle_match_found (self, model, tree_iter):

        line_index = model.get_path (tree_iter)[0]
        self.matches.append (line_index)

        if len (self.matches) == 1:
            self.scroll_view_to_line (line_index)
        elif len (self.matches) > 10000:
            self.sentinel.abort ()

    def handle_search_complete (self):

        self.logger.debug ("search for %r complete, got %i results",
                           self.operation.search_string,
                           len (self.matches))

class Plugin (PluginBase):

    features = [FindBarFeature]