# -*- coding: utf-8 -*-
#
#  finder.py - finder commander module
#
#  Copyright (C) 2010 - Jesse van den Kieboom
#
#  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 2 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, write to the Free Software
#  Foundation, Inc., 51 Franklin Street, Fifth Floor,
#  Boston, MA 02110-1301, USA.

from xml.sax import saxutils
import commander.commands.result
import commander.utils as utils
from gi.repository import Gdk, Gtk

class Finder:
    FIND_STARTMARK = 'gedit-commander-find-startmark'
    FIND_ENDMARK = 'gedit-commander-find-endmark'

    FIND_RESULT_STARTMARK = 'gedit-commander-find-result-startmark'
    FIND_RESULT_ENDMARK = 'gedit-commander-find-result-endmark'

    def __init__(self, entry):
        self.entry = entry
        self.view = entry.view()

        self.findstr = None
        self.replacestr = None

        self.search_boundaries = utils.Struct({'start': None, 'end': None})
        self.find_result = utils.Struct({'start': None, 'end': None})

        self.unescapes = [
            ['\\n', '\n'],
            ['\\r', '\r'],
            ['\\t', '\t']
        ]

        self.from_start = False
        self.search_start_mark = None

    def unescape(self, s):
        for esc in self.unescapes:
            s = s.replace(esc[0], esc[1])

        return s

    def do_find(self, bounds):
        return None

    def get_replace(self, text):
        return self.replacestr

    def set_replace(self, replacestr):
        self.replacestr = self.unescape(replacestr)

    def set_find(self, findstr):
        self.findstr = self.unescape(findstr)

    def get_find(self):
        return self.findstr

    def select_last_result(self):
        buf = self.view.get_buffer()

        startiter = buf.get_iter_at_mark(self.find_result.start)
        enditer = buf.get_iter_at_mark(self.find_result.end)

        buf.select_range(startiter, enditer)

        visible = self.view.get_visible_rect()
        loc = self.view.get_iter_location(startiter)

        # Scroll there if needed
        if loc.y + loc.height < visible.y or loc.y > visible.y + visible.height:
            self.view.scroll_to_iter(startiter, 0.2, True, 0, 0.5)

    def find_next(self, select=False):
        buf = self.view.get_buffer()

        # Search from the end of the last result to the end of the search boundary
        bounds = [buf.get_iter_at_mark(self.find_result.end),
                  buf.get_iter_at_mark(self.search_boundaries.end)]

        ret = self.do_find(bounds)

        # Check if we need to wrap around if nothing is found
        if self.search_start_mark:
            startiter = buf.get_iter_at_mark(self.search_start_mark)
        else:
            startiter = None

        startbound = buf.get_iter_at_mark(self.search_boundaries.start)

        if not ret and not self.from_start and (startiter and not startiter.equal(startbound)):
            self.from_start = True

            # Try from beginning
            bounds[0] = buf.get_start_iter()
            bounds[1] = startiter

            # Make sure to just stop at the start of the previous
            self.search_boundaries.end = self.search_start_mark

            ret = self.do_find(bounds)

        if not ret:
            return False
        else:
            # Mark find result
            buf.move_mark(self.find_result.start, ret[0])
            buf.move_mark(self.find_result.end, ret[1])

            if select:
                self.select_last_result()

            return True

    def _create_or_move(self, markname, piter, left_gravity):
        buf = self.view.get_buffer()
        mark = buf.get_mark(markname)

        if not mark:
            mark = buf.create_mark(markname, piter, left_gravity)
        else:
            buf.move_mark(mark, piter)

        return mark

    def find_first(self, doend=True, select=False):
        words = []
        buf = self.view.get_buffer()

        while not self.findstr:
            fstr, words, modifier = (yield commander.commands.result.Prompt('Find:'))

            if fstr:
                self.set_find(fstr)

        # Determine search area
        bounds = list(buf.get_selection_bounds())

        if self.search_start_mark:
            buf.delete_mark(self.search_start_mark)
            self.search_start_mark = None

        if not bounds:
            # Search in the whole buffer, from the current cursor position on to the
            # end, and then continue to start from the beginning of the buffer if needed
            bounds = list(buf.get_bounds())
            self.search_start_mark = buf.create_mark(None, buf.get_iter_at_mark(buf.get_insert()), True)
            selection = False
        else:
            selection = True

        bounds[0].order(bounds[1])

        # Set marks at the boundaries
        self.search_boundaries.start = self._create_or_move(Finder.FIND_STARTMARK, bounds[0], True)
        self.search_boundaries.end = self._create_or_move(Finder.FIND_ENDMARK, bounds[1], False)

        # Set the result marks so the next find will start at the correct location
        if selection:
            piter = bounds[0]
        else:
            piter = buf.get_iter_at_mark(buf.get_insert())

        self.find_result.start = self._create_or_move(Finder.FIND_RESULT_STARTMARK, piter, True)
        self.find_result.end = self._create_or_move(Finder.FIND_RESULT_ENDMARK, piter, False)

        if not self.find_next(select=select):
            if doend:
                self.entry.info_show('<i>Search hit end of the document</i>', True)

            yield commander.commands.result.DONE
        else:
            yield True

    def cancel(self):
        buf = self.view.get_buffer()

        buf.set_search_text('', 0)
        buf.move_mark(buf.get_selection_bound(), buf.get_iter_at_mark(buf.get_insert()))

        if self.search_start_mark:
            buf.delete_mark(self.search_start_mark)

    def find(self, findstr):
        if findstr:
            self.set_find(findstr)

        buf = self.view.get_buffer()

        try:
            if (yield self.find_first(select=True)):
                while True:
                    argstr, words, modifier = (yield commander.commands.result.Prompt('Search next [<i>%s</i>]:' % (saxutils.escape(self.findstr),)))

                    if argstr:
                        self.set_find(argstr)

                    if not self.find_next(select=True):
                        break

                self.entry.info_show('<i>Search hit end of the document</i>', True)
        except GeneratorExit as e:
            self.cancel()
            raise e

        self.cancel()
        yield commander.commands.result.DONE

    def _restore_cursor(self, mark):
        buf = mark.get_buffer()

        buf.place_cursor(buf.get_iter_at_mark(mark))
        buf.delete_mark(mark)

        self.view.scroll_to_mark(buf.get_insert(), 0.2, True, 0, 0.5)

    def get_current_replace(self):
        buf = self.view.get_buffer()
        bounds = utils.Struct({'start': buf.get_iter_at_mark(self.find_result.start),
                               'end': buf.get_iter_at_mark(self.find_result.end)})

        if not bounds.start.equal(bounds.end):
            text = bounds.start.get_text(bounds.end)
            return self.get_replace(text)
        else:
            return self.replacestr

    def replace(self, findstr, replaceall=False, replacestr=None):
        if findstr:
            self.set_find(findstr)

        if replacestr != None:
            self.set_replace(replacestr)

        # First find something
        buf = self.view.get_buffer()

        if replaceall:
            startmark = buf.create_mark(None, buf.get_iter_at_mark(buf.get_insert()), False)

        ret = (yield self.find_first(select=not replaceall))

        if not ret:
            yield commander.commands.result.DONE

        self.scroll_back = False

        # Then ask for the replacement string
        if not self.replacestr:
            try:
                if replaceall:
                    self.scroll_back = True
                    self.select_last_result()

                replacestr, words, modifier = (yield commander.commands.result.Prompt('Replace with:'))
                self.set_replace(replacestr)
            except GeneratorExit as e:
                if replaceall:
                    self._restore_cursor(startmark)

                self.cancel()
                raise e

        # On replace all, wrap it in begin/end user action
        if replaceall:
            buf.begin_user_action()

        try:
            while True:
                if not replaceall:
                    rep, words, modifier = (yield commander.commands.result.Prompt('Replace next [%s]:' % (saxutils.escape(self.get_current_replace()),)))

                    if rep:
                        self.set_replace(rep)

                bounds = utils.Struct({'start': buf.get_iter_at_mark(self.find_result.start),
                                       'end': buf.get_iter_at_mark(self.find_result.end)})

                # If there is a selection, replace it with the replacement string
                if not bounds.start.equal(bounds.end) and (replaceall or not (modifier & Gdk.ModifierType.CONTROL_MASK)):
                    text = bounds.start.get_text(bounds.end)
                    repl = self.get_replace(text)

                    buf.begin_user_action()
                    buf.delete(bounds.start, bounds.end)
                    buf.insert(bounds.start, repl)
                    buf.end_user_action()

                # Find next
                if not self.find_next(select=not replaceall):
                    if not replaceall:
                        self.entry.info_show('<i>Search hit end of the document</i>', True)

                    break

        except GeneratorExit as e:
            if replaceall:
                self._restore_cursor(startmark)
                buf.end_user_action()

            self.cancel()
            raise e

        if replaceall:
            if self.scroll_back:
                self._restore_cursor(startmark)

            buf.end_user_action()

        self.cancel()
        yield commander.commands.result.DONE

# vi:ex:ts=4:et
