# -*- coding: utf-8 -*-
# vim: autoindent shiftwidth=4 expandtab textwidth=80 tabstop=4 softtabstop=4

###############################################################################
# OpenLP - Open Source Lyrics Projection                                      #
# --------------------------------------------------------------------------- #
# Copyright (c) 2008-2011 Raoul Snyman                                        #
# Portions copyright (c) 2008-2011 Tim Bentley, Gerald Britton, Jonathan      #
# Corwin, Michael Gorven, Scott Guerrieri, Matthias Hub, Meinert Jordan,      #
# Armin Köhler, Joshua Miller, Stevan Pettit, Andreas Preikschat, Mattias     #
# Põldaru, Christian Richter, Philip Ridout, Simon Scudder, Jeffrey Smith,    #
# Maikel Stuivenberg, Martin Thompson, Jon Tibble, Frode Woldsund             #
# --------------------------------------------------------------------------- #
# 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; version 2 of the License.                              #
#                                                                             #
# 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., 59  #
# Temple Place, Suite 330, Boston, MA 02111-1307 USA                          #
###############################################################################

import logging
import re

from lxml import objectify
from lxml.etree import Error, LxmlError

from openlp.plugins.songs.lib import VerseType
from openlp.plugins.songs.lib.songimport import SongImport
from openlp.plugins.songs.lib.ui import SongStrings

log = logging.getLogger(__name__)

class OpenSongImport(SongImport):
    """
    Import songs exported from OpenSong

    The format is described loosly on the `OpenSong File Format Specification
    <http://www.opensong.org/d/manual/song_file_format_specification>`_ page on
    the OpenSong web site. However, it doesn't describe the <lyrics> section,
    so here's an attempt:

    Verses can be expressed in one of 2 ways, either in complete verses, or by
    line grouping, i.e. grouping all line 1's of a verse together, all line 2's
    of a verse together, and so on.

    An example of complete verses::

        <lyrics>
        [v1]
         List of words
         Another Line

        [v2]
         Some words for the 2nd verse
         etc...
        </lyrics>

    The 'v' in the verse specifiers above can be left out, it is implied.

    An example of line grouping::

        <lyrics>
        [V]
        1List of words
        2Some words for the 2nd Verse

        1Another Line
        2etc...
        </lyrics>

    Either or both forms can be used in one song. The number does not
    necessarily appear at the start of the line. Additionally, the [v1] labels
    can have either upper or lower case Vs.

    Other labels can be used also:

    C
        Chorus

    B
        Bridge

    All verses are imported and tagged appropriately.

    Guitar chords can be provided "above" the lyrics (the line is preceeded by
    a period "."), and one or more "_" can be used to signify long-drawn-out
    words. Chords and "_" are removed by this importer. For example::

        . A7        Bm
        1 Some____ Words

    The <presentation> tag is used to populate the OpenLP verse display order
    field. The Author and Copyright tags are also imported to the appropriate
    places.

    """
    def __init__(self, manager, **kwargs):
        """
        Initialise the class.
        """
        SongImport.__init__(self, manager, **kwargs)

    def doImport(self):
        self.importWizard.progressBar.setMaximum(len(self.importSource))
        for filename in self.importSource:
            if self.stopImportFlag:
                return
            song_file = open(filename)
            self.doImportFile(song_file)
            song_file.close()

    def doImportFile(self, file):
        """
        Process the OpenSong file - pass in a file-like object, not a file path.
        """
        self.setDefaults()
        try:
            tree = objectify.parse(file)
        except (Error, LxmlError):
            self.logError(file.name, SongStrings.XMLSyntaxError)
            log.exception(u'Error parsing XML')
            return
        root = tree.getroot()
        fields = dir(root)
        decode = {
            u'copyright': self.addCopyright,
            u'ccli': u'ccli_number',
            u'author': self.parseAuthor,
            u'title': u'title',
            u'aka': u'alternate_title',
            u'hymn_number': u'song_number'
        }
        for attr, fn_or_string in decode.items():
            if attr in fields:
                ustring = unicode(root.__getattr__(attr))
                if isinstance(fn_or_string, basestring):
                    setattr(self, fn_or_string, ustring)
                else:
                    fn_or_string(ustring)
        if u'theme' in fields and unicode(root.theme) not in self.topics:
            self.topics.append(unicode(root.theme))
        if u'alttheme' in fields and unicode(root.alttheme) not in self.topics:
            self.topics.append(unicode(root.alttheme))
        # data storage while importing
        verses = {}
        # keep track of verses appearance order
        our_verse_order = []
        # default verse
        verse_tag = VerseType.Tags[VerseType.Verse]
        verse_num = u'1'
        # for the case where song has several sections with same marker
        inst = 1
        if u'lyrics' in fields:
            lyrics = unicode(root.lyrics)
        else:
            lyrics = u''
        for this_line in lyrics.split(u'\n'):
            # remove comments
            semicolon = this_line.find(u';')
            if semicolon >= 0:
                this_line = this_line[:semicolon]
            this_line = this_line.strip()
            if not len(this_line):
                continue
            # skip guitar chords and page and column breaks
            if this_line.startswith(u'.') or this_line.startswith(u'---') \
                or this_line.startswith(u'-!!'):
                continue
            # verse/chorus/etc. marker
            if this_line.startswith(u'['):
                # drop the square brackets
                right_bracket = this_line.find(u']')
                content = this_line[1:right_bracket].lower()
                # have we got any digits?
                # If so, verse number is everything from the digits
                # to the end (even if there are some alpha chars on the end)
                match = re.match(u'(\D*)(\d+.*)', content)
                if match is not None:
                    verse_tag = match.group(1)
                    verse_num = match.group(2)
                else:
                    # otherwise we assume number 1 and take the whole prefix as
                    # the verse tag
                    verse_tag = content
                    verse_num = u'1'
                if len(verse_tag) == 0:
                    verse_index = 0
                else:
                    verse_index = VerseType.from_loose_input(verse_tag)
                verse_tag = VerseType.Tags[verse_index]
                inst = 1
                if [verse_tag, verse_num, inst] in our_verse_order \
                    and verses.has_key(verse_tag) \
                    and verses[verse_tag].has_key(verse_num):
                    inst = len(verses[verse_tag][verse_num]) + 1
                continue
            # number at start of line.. it's verse number
            if this_line[0].isdigit():
                verse_num = this_line[0]
                this_line = this_line[1:].strip()
                our_verse_order.append([verse_tag, verse_num, inst])
            if not verses.has_key(verse_tag):
                verses[verse_tag] = {}
            if not verses[verse_tag].has_key(verse_num):
                verses[verse_tag][verse_num] = {}
            if not verses[verse_tag][verse_num].has_key(inst):
                verses[verse_tag][verse_num][inst] = []
                our_verse_order.append([verse_tag, verse_num, inst])
            # Tidy text and remove the ____s from extended words
            this_line = self.tidyText(this_line)
            this_line = this_line.replace(u'_', u'')
            this_line = this_line.replace(u'|', u'\n')
            verses[verse_tag][verse_num][inst].append(this_line)
        # done parsing
        # add verses in original order
        for (verse_tag, verse_num, inst) in our_verse_order:
            verse_def = u'%s%s' % (verse_tag, verse_num)
            lines = u'\n'.join(verses[verse_tag][verse_num][inst])
            self.addVerse(lines, verse_def)
        if not self.verses:
            self.addVerse('')
        # figure out the presentation order, if present
        if u'presentation' in fields and root.presentation:
            order = unicode(root.presentation)
            # We make all the tags in the lyrics lower case, so match that here
            # and then split into a list on the whitespace
            order = order.lower().split()
            for verse_def in order:
                match = re.match(u'(\D*)(\d+.*)', verse_def)
                if match is not None:
                    verse_tag = match.group(1)
                    verse_num = match.group(2)
                    if not len(verse_tag):
                        verse_tag =  VerseType.Tags[VerseType.Verse]
                else:
                    # Assume it's no.1 if there are no digits
                    verse_tag = verse_def
                    verse_num = u'1'
                verse_def = u'%s%s' % (verse_tag, verse_num)
                if verses.has_key(verse_tag) and \
                    verses[verse_tag].has_key(verse_num):
                    self.verseOrderList.append(verse_def)
                else:
                    log.info(u'Got order %s but not in verse tags, dropping'
                        u'this item from presentation order', verse_def)
        if not self.finish():
            self.logError(file.name)
