# -*- coding: utf-8 -*-
# Copyright 2004-2005 Joe Wreschnig, Michael Urman, Iñigo Serna
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation

from gi.repository import Gtk, GLib, Pango

from quodlibet import qltk
from quodlibet import util

from quodlibet.qltk import Button, Icons
from quodlibet.formats import AudioFile
from quodlibet.pattern import XMLFromPattern, XMLFromMarkupPattern, \
    error as PatternError
from quodlibet.util import connect_obj

try:
    import gi
    gi.require_version("GtkSource", "3.0")
    from gi.repository import GtkSource
except (ValueError, ImportError):
    TextView = Gtk.TextView
    TextBuffer = Gtk.TextBuffer
else:
    TextView = GtkSource.View

    class TextBuffer(GtkSource.Buffer):
        def __init__(self, *args):
            super(TextBuffer, self).__init__(*args)
            self.set_highlight_matching_brackets(False)
            self.set_highlight_syntax(False)

        def set_text(self, *args):
            self.begin_not_undoable_action()
            super(TextBuffer, self).set_text(*args)
            self.end_not_undoable_action()


class TextEditBox(Gtk.HBox):
    """A simple text editing area with a default value, a revert button,
    and an apply button. The 'buffer' attribute is the text buffer, the
    'apply' attribute is the apply button.

    FIXME: Button text should changable (without poking the buttons directly).
    """

    def __init__(self, default=""):
        super(TextEditBox, self).__init__(spacing=6)

        sw = Gtk.ScrolledWindow()
        sw.set_shadow_type(Gtk.ShadowType.IN)
        sw.set_policy(Gtk.PolicyType.AUTOMATIC, Gtk.PolicyType.AUTOMATIC)
        sw.add(TextView(buffer=TextBuffer()))
        self.pack_start(sw, True, True, 0)
        self.buffer = sw.get_child().get_buffer()

        box = Gtk.VBox(spacing=6)
        rev = Button(_("_Revert"), Icons.DOCUMENT_REVERT)
        app = Button(_("_Apply"))
        box.pack_start(rev, False, True, 0)
        box.pack_start(app, False, True, 0)
        self.pack_start(box, False, True, 0)
        connect_obj(rev, 'clicked', self.buffer.set_text, default)
        self.revert = rev
        self.apply = app

    @property
    def text(self):
        start, end = self.buffer.get_bounds()
        return self.buffer.get_text(start, end, True).decode('utf-8')

    @text.setter
    def text(self, value):
        self.buffer.set_text(value, -1)


def validate_markup_pattern(text, alternative_markup=True, links=False):
    """Check whether a passed pattern results in a valid pango markup.

    Args:
        text (unicode): the pattern
        alternative_markup (bool): if "[b]" gets mapped to "\<b\>"
        links (bool): if link tags are allowed (for Gtk.Label only)

    Raises:
        ValueError: In case the pattern isn't valid
    """

    assert isinstance(text, unicode)

    f = AudioFile({"~filename": "dummy"})

    try:
        if alternative_markup:
            pattern = XMLFromMarkupPattern(text)
        else:
            pattern = XMLFromPattern(text)
        text = pattern % f
    except PatternError as e:
        return ValueError(e)

    try:
        Pango.parse_markup(text, -1, u"\u0000")
    except GLib.GError as e:
        if not links:
            raise ValueError(e)
        # Gtk.Label supports links on top of pango markup but doesn't
        # provide a way to verify them. We can check if the markup
        # was accepted by seeing if get_text() returns something.
        l = Gtk.Label()
        # add a character in case text is empty.
        # this might print a warning to stderr.. no idea how to prevent that..
        l.set_markup(text + " ")
        if not l.get_text():
            raise ValueError(e)


class PatternEditBox(TextEditBox):
    """A TextEditBox that stops the apply button's clicked signal if
    the pattern is invalid. You need to use connect_after to connect to
    it, to get this feature."""

    def __init__(self, default="", alternative_markup=True, links=False):
        super(PatternEditBox, self).__init__(default)
        self._alternative_markup = alternative_markup
        self._links = links
        self.apply.connect('clicked', self.__check_markup)

    def __check_markup(self, apply):
        try:
            validate_markup_pattern(
                self.text, self._alternative_markup, self._links)
        except ValueError as e:
            qltk.ErrorMessage(
                self, _("Invalid pattern"),
                _("The pattern you entered was invalid. Make sure you enter "
                  "&lt; and &gt; as \\&lt; and \\&gt; and that your tags are "
                  "balanced.\n\n%s") % util.escape(str(e))).run()
            apply.stop_emission('clicked')
        return False


class TextEdit(qltk.UniqueWindow):
    """A window with a text editing box in it."""

    Box = TextEditBox

    def __init__(self, parent, default="", **kwargs):
        if self.is_not_unique():
            return
        super(TextEdit, self).__init__()
        self.set_title(_("Edit Display"))
        self.set_transient_for(qltk.get_top_parent(parent))
        self.set_border_width(12)
        self.set_default_size(420, 190)

        vbox = Gtk.VBox(spacing=12)
        close = Button(_("_Close"), Icons.WINDOW_CLOSE)
        close.connect('clicked', lambda *x: self.destroy())
        b = Gtk.HButtonBox()
        b.set_layout(Gtk.ButtonBoxStyle.END)
        b.pack_start(close, True, True, 0)

        self.box = box = self.Box(default, **kwargs)
        vbox.pack_start(box, True, True, 0)
        self.use_header_bar()
        if not self.has_close_button():
            vbox.pack_start(b, False, True, 0)

        self.add(vbox)
        self.apply = box.apply
        self.revert = box.revert

        close.grab_focus()
        self.get_child().show_all()

    @property
    def text(self):
        return self.box.text

    @text.setter
    def text(self, value):
        self.box.text = value


class PatternEdit(TextEdit):
    """A window with a pattern editing box in it."""
    Box = PatternEditBox
