[meld] Rewrite historyentry for simplified HistoryCombo use

[Kai Willadsen <kaiw src gnome org>]

commit 25e55768b1ee0e4dd9901fe762f457d98c509fb5
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sun Aug 11 10:05:17 2013 +1000

    Rewrite historyentry for simplified HistoryCombo use
    
    This commit also removes all use of gconf for storing history data.
    It was never a great idea to store history data in gconf, and was only
    done because GnomeEntry did so. In a gsettings-based future, this
    makes even less sense.

 data/ui/vcview.ui       |    2 +-
 meld/ui/historyentry.py |  252 +++++++++++++---------------------------------
 2 files changed, 72 insertions(+), 182 deletions(-)
---
diff --git a/data/ui/vcview.ui b/data/ui/vcview.ui
index e870244..b4b1bb0 100644
--- a/data/ui/vcview.ui
+++ b/data/ui/vcview.ui
@@ -559,7 +559,7 @@
                             <child>
                               <object class="HistoryCombo" id="previousentry">
                                 <property name="visible">True</property>
-                                <property name="history-id">previousentry</property>
+                                <property name="history-id">commit-messages</property>
                                 <signal handler="on_previousentry_activate" name="changed"/>
                               </object>
                               <packing>
diff --git a/meld/ui/historyentry.py b/meld/ui/historyentry.py
index 52415f2..e96e873 100644
--- a/meld/ui/historyentry.py
+++ b/meld/ui/historyentry.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2008-2009 Kai Willadsen <kai willadsen gmail com>
+# Copyright (C) 2008-2009, 2013 Kai Willadsen <kai willadsen gmail com>
 #
 # 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
@@ -15,13 +15,16 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 # USA.
 
+import ConfigParser
+import os
+import sys
+
 import glib
-import gtk
 import gobject
+import gtk
 import pango
-# gconf is also imported; see end of HistoryEntry class for details
 
-# This file is a Python translation of:
+# This file started off as a Python translation of:
 #  * gedit/gedit/gedit-history-entry.c
 #  * libgnomeui/libgnomeui/gnome-file-entry.c
 # roughly based on Colin Walters' Python translation of msgarea.py from Hotwire
@@ -35,7 +38,7 @@ def _remove_item(store, text):
         return False
 
     for row in store:
-        if row[0] == text:
+        if row[1] == text:
             store.remove(row.iter)
             return True
     return False
@@ -52,228 +55,115 @@ def _clamp_list_store(liststore, max_items):
         valid = liststore.remove(it)
 
 
-def _escape_cell_data_func(col, renderer, model, it, escape_func):
-    string = model.get(it, 0)
-    escaped = escape_func(string)
-    renderer.set("text", escaped)
+class HistoryCombo(gtk.ComboBox):
+    __gtype_name__ = "HistoryCombo"
 
+    __gproperties__ = {
+        "history-id": (str, "History ID",
+                       "Identifier associated with entry's history store",
+                       None,
+                       gobject.PARAM_CONSTRUCT_ONLY | gobject.PARAM_READWRITE),
+        "history-length": (int, "History length",
+                           "Number of history items to display in the combo",
+                           1, 20, HISTORY_ENTRY_HISTORY_LENGTH_DEFAULT,
+                           gobject.PARAM_READWRITE),
+    }
 
-class HistoryWidget(object):
+    def __init__(self, **kwargs):
+        super(HistoryCombo, self).__init__(**kwargs)
+
+        if sys.platform == "win32":
+            pref_dir = os.path.join(os.getenv("APPDATA"), "Meld")
+        else:
+            pref_dir = os.path.join(glib.get_user_config_dir(), "meld")
 
-    def __init__(self, history_id=None, enable_completion=False, **kwargs):
-        self._history_id = history_id
+        if not os.path.exists(pref_dir):
+            os.makedirs(pref_dir)
+
+        self.history_file = os.path.join(pref_dir, "history.ini")
+        self.config = ConfigParser.SafeConfigParser()
+        if os.path.exists(self.history_file):
+            self.config.read(self.history_file)
+
+        self._history_id = None
         self._history_length = HISTORY_ENTRY_HISTORY_LENGTH_DEFAULT
-        self._completion = None
-        self._get_gconf_client()
 
-        self.set_model(gtk.ListStore(str))
-        self.set_enable_completion(enable_completion)
+        self.set_model(gtk.ListStore(str, str))
+        rentext = gtk.CellRendererText()
+        rentext.props.width_chars = 60
+        rentext.props.ellipsize = pango.ELLIPSIZE_END
+        self.pack_start(rentext, True)
+        self.set_attributes(rentext, text=0)
 
     def do_get_property(self, pspec):
         if pspec.name == "history-id":
             return self._history_id
+        elif pspec.name == "history-length":
+            return self._history_length
         else:
             raise AttributeError("Unknown property: %s" % pspec.name)
 
     def do_set_property(self, pspec, value):
         if pspec.name == "history-id":
-            # FIXME: if we change history-id after our store is populated, odd
-            # things might happen
-            store = self.get_model()
-            store.clear()
             self._history_id = value
             self._load_history()
+        elif pspec.name == "history-length":
+            if value <= 0:
+                raise ValueError("History length cannot be less than one")
+            self._history_length = value
+            if len(self.get_model()) > self._history_length:
+                self._load_history()
         else:
             raise AttributeError("Unknown property: %s" % pspec.name)
 
-    def _get_gconf_client(self):
-        self._gconf_client = gconf.client_get_default()
-
-    def _get_history_key(self):
-        # We store data under /apps/gnome-settings/ like GnomeEntry did.
-        if not self._history_id:
-            return None
-        key = ''.join(["/apps/gnome-settings/", "meld", "/history-",
-                       gconf.escape_key(self._history_id, -1)])
-        return key
-
-    def _save_history(self):
-        key = self._get_history_key()
-        if key is None:
-            return
-        gconf_items = [row[0] for row in self.get_model()]
-        self._gconf_client.set_list(key, gconf.VALUE_STRING, gconf_items)
-
-    def _insert_history_item(self, text, prepend):
-        if len(text) <= MIN_ITEM_LEN:
-            return
-
-        store = self.get_model()
-        if not _remove_item(store, text):
-            _clamp_list_store(store, self._history_length - 1)
-
-        if (prepend):
-            store.insert(0, (text,))
-        else:
-            store.append((text,))
-        self._save_history()
-
     def prepend_history(self, text):
-        if not text:
-            return
         self._insert_history_item(text, True)
 
     def append_history(self, text):
-        if not text:
-            return
         self._insert_history_item(text, False)
 
-    def _load_history(self):
-        key = self._get_history_key()
-        if key is None:
-            return
-        gconf_items = self._gconf_client.get_list(key, gconf.VALUE_STRING)
-
-        store = self.get_model()
-        store.clear()
-
-        for item in gconf_items[:self._history_length - 1]:
-            store.append((item,))
-
     def clear(self):
-        store = self.get_model()
-        store.clear()
+        self.get_model().clear()
         self._save_history()
 
-    def set_history_length(self, max_saved):
-        if max_saved <= 0:
-            return
-        self._history_length = max_saved
-        if len(self.get_model()) > max_saved:
-            self._load_history()
-
-    def get_history_length(self):
-        return self._history_length
-
-    def set_enable_completion(self, enable):
-        if enable:
-            if self._completion is not None:
-                return
-            self._completion = gtk.EntryCompletion()
-            self._completion.set_model(self.get_model())
-            self._completion.set_text_column(0)
-            self._completion.set_minimum_key_length(MIN_ITEM_LEN)
-            self._completion.set_popup_completion(False)
-            self._completion.set_inline_completion(True)
-            self.child.set_completion(self._completion)
-        else:
-            if self._completion is None:
-                return
-            self.get_entry().set_completion(None)
-            self._completion = None
-
-    def get_enable_completion(self):
-        return self._completion is not None
-
-    def get_entry(self):
-        return self.child
-
-    def focus_entry(self):
-        self.child.grab_focus()
-
-    def set_escape_func(self, escape_func):
-        cells = self.get_cells()
-        # We only have one cell renderer
-        if len(cells) == 0 or len(cells) > 1:
-            return
-
-        if escape_func is not None:
-            self.set_cell_data_func(cells[0], _escape_cell_data_func, escape_func)
-        else:
-            self.set_cell_data_func(cells[0], None, None)
-
-
-# TODO: There is no point having this separation now
-
-class HistoryCombo(gtk.ComboBox, HistoryWidget):
-    __gtype_name__ = "HistoryCombo"
-
-    __gproperties__ = {
-        "history-id": (str, "History ID",
-                       "Identifier associated with entry's history store",
-                       None, gobject.PARAM_READWRITE),
-    }
-
-    def __init__(self, history_id=None, **kwargs):
-        super(HistoryCombo, self).__init__(**kwargs)
-        HistoryWidget.__init__(self, history_id)
-        self.set_model(gtk.ListStore(str, str))
-        rentext = gtk.CellRendererText()
-        rentext.props.width_chars = 60
-        rentext.props.ellipsize = pango.ELLIPSIZE_END
-        self.pack_start(rentext, True)
-        self.set_attributes(rentext, text=0)
-
-    def _save_history(self):
-        key = self._get_history_key()
-        if key is None:
-            return
-        gconf_items = [row[1] for row in self.get_model()]
-        self._gconf_client.set_list(key, gconf.VALUE_STRING, gconf_items)
-
     def _insert_history_item(self, text, prepend):
-        if len(text) <= MIN_ITEM_LEN:
+        if not text or len(text) <= MIN_ITEM_LEN:
             return
 
-        # Redefining here to key off the full text, not the first line
-        def _remove_item(store, text):
-            if text is None:
-                return False
-
-            for row in store:
-                if row[1] == text:
-                    store.remove(row.iter)
-                    return True
-            return False
-
         store = self.get_model()
         if not _remove_item(store, text):
             _clamp_list_store(store, self._history_length - 1)
 
         row = (text.splitlines()[0], text)
 
-        if (prepend):
+        if prepend:
             store.insert(0, row)
         else:
             store.append(row)
         self._save_history()
 
     def _load_history(self):
-        key = self._get_history_key()
-        if key is None:
+        section_key = self._history_id
+        if section_key is None or not self.config.has_section(section_key):
             return
-        gconf_items = self._gconf_client.get_list(key, gconf.VALUE_STRING)
 
         store = self.get_model()
         store.clear()
+        paths = sorted(self.config.items(section_key))
+        for key, path in paths[:self._history_length - 1]:
+            path = path.decode("string-escape")
+            firstline = path.splitlines()[0]
+            store.append((firstline, path))
 
-        # This override is here to handle multi-line commit messages, and is
-        # specific to HistoryCombo use in VcView.
-        for item in gconf_items[:self._history_length - 1]:
-            firstline = item.splitlines()[0]
-            store.append((firstline, item))
-
-
-try:
-    import gconf
-    # Verify that gconf is actually working (bgo#666136)
-    client = gconf.client_get_default()
-    key = '/apps/meld/gconf-test'
-    client.set_int(key, os.getpid())
-    client.unset(key)
-except (ImportError, glib.GError):
-    do_nothing = lambda *args: None
-    for m in ('_save_history', '_load_history', '_get_gconf_client'):
-        setattr(HistoryWidget, m, do_nothing)
-        setattr(HistoryCombo, m, do_nothing)
+    def _save_history(self):
+        section_key = self._history_id
+        if section_key is None:
+            return
 
+        self.config.remove_section(section_key)
+        self.config.add_section(section_key)
+        for i, row in enumerate(self.get_model()):
+            message = row[1].encode('string-escape')
+            self.config.set(section_key, "item%d" % i, message)
+        with open(self.history_file, 'w') as f:
+            self.config.write(f)