# This file is part of lyx2lyx
# -*- coding: iso-8859-1 -*-
# Copyright (C) 2002-2004 Dekel Tsur <dekel@lyx.org>, José Matos <jamatos@lyx.org>
#
# 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

from parser_tools import get_value, check_token, find_token
import os.path
import gzip
import sys
import re
import string

##
# file format version
#
version = "1.4.0cvs"
default_debug_level = 2
format_re = re.compile(r"(\d)[\.,]?(\d\d)")
fileformat = re.compile(r"\\lyxformat\s*(\S*)")
original_version = re.compile(r"\#LyX (\S*)")

format_relation = [("0_10",  [210], ["0.10.7","0.10"]),
                   ("0_12",  [215], ["0.12","0.12.1","0.12"]),
                   ("1_0_0", [215], ["1.0.0","1.0"]),
                   ("1_0_1", [215], ["1.0.1","1.0.2","1.0.3","1.0.4", "1.1.2","1.1"]),
                   ("1_1_4", [215], ["1.1.4","1.1"]),
                   ("1_1_5", [216], ["1.1.5","1.1.5fix1","1.1.5fix2","1.1"]),
                   ("1_1_6", [217], ["1.1.6","1.1.6fix1","1.1.6fix2","1.1"]),
                   ("1_1_6fix3", [218], ["1.1.6fix3","1.1.6fix4","1.1"]),
                   ("1_2", [220], ["1.2.0","1.2.1","1.2.3","1.2.4","1.2"]),
                   ("1_3", [221], ["1.3.0","1.3.1","1.3.2","1.3.3","1.3.4","1.3.5","1.3"]),
                   ("1_4", range(223,238), ["1.4.0cvs","1.4"])]


def formats_list():
    formats = []
    for version in format_relation:
        for format in version[1]:
            if format not in formats:
                formats.append(format)
    return formats


def get_end_format():
    return format_relation[-1][1][-1]


def get_backend(textclass):
    if textclass == "linuxdoc" or textclass == "manpage":
        return "linuxdoc"
    if textclass[:7] == "docbook":
        return "docbook"
    return "latex"


##
# Class
#
class FileInfo:
    """This class carries all the information of the LyX file."""
    def __init__(self, end_format = 0, input = "", output = "", error = "", debug = default_debug_level):
        if input and input != '-':
            self.input = self.open(input)
        else:
            self.input = sys.stdin
        if output:
            self.output = open(output, "w")
        else:
            self.output = sys.stdout

        if error:
            self.err = open(error, "w")
        else:
            self.err = sys.stderr

        self.debug = debug

        if end_format:
            self.end_format = self.lyxformat(end_format)
        else:
            self.end_format = get_end_format()

        self.backend = "latex"
        self.textclass = "article"
        self.header = []
        self.body = []
        self.read()

    def warning(self, message, debug_level= default_debug_level):
        if debug_level <= self.debug:
            self.err.write(message + "\n")

    def error(self, message):
        self.warning(message)
        self.warning("Quiting.")
        sys.exit(1)

    def read(self):
        """Reads a file into the self.header and self.body parts"""
        preamble = 0

        while 1:
            line = self.input.readline()
            if not line:
                self.error("Invalid LyX file.")

            line = line[:-1]
            # remove '\r' from line's end, if present
            if line[-1:] == '\r':
                line = line[:-1]

            if check_token(line, '\\begin_preamble'):
                preamble = 1
            if check_token(line, '\\end_preamble'):
                preamble = 0

            if not preamble:
                line = string.strip(line)

            if not line and not preamble:
                break

            self.header.append(line)

        while 1:
            line = self.input.readline()
            if not line:
                break
            # remove '\r' from line's end, if present
            if line[-2:-1] == '\r':
                self.body.append(line[:-2])
            else:
                self.body.append(line[:-1])

        self.textclass = get_value(self.header, "\\textclass", 0)
        self.backend = get_backend(self.textclass)
        self.format  = self.read_format()
        self.language = get_value(self.header, "\\language", 0)
        if self.language == "":
            self.language = "english"
        self.initial_version = self.read_version()

    def write(self):
        self.set_version()
        self.set_format()

        for line in self.header:
            self.output.write(line+"\n")
        self.output.write("\n")
        for line in self.body:
            self.output.write(line+"\n")


    def open(self, file):
        """Transparently deals with compressed files."""

        self.dir = os.path.dirname(os.path.abspath(file))
        try:
            gzip.open(file).readline()
            self.output = gzip.GzipFile("","wb",6,self.output)
            return gzip.open(file)
        except:
            return open(file)

    def lyxformat(self, format):
        result = format_re.match(format)
        if result:
            format = int(result.group(1) + result.group(2))
        else:
            self.error(str(format) + ": " + "Invalid LyX file.")

        if format in formats_list():
            return format

        self.error(str(format) + ": " + "Format not supported.")
        return None

    def read_version(self):
        for line in self.header:
            if line[0] != "#":
                return None

            result = original_version.match(line)
            if result:
                return result.group(1)
        return None

    def set_version(self):
        self.header[0] = "#LyX %s created this file. For more info see http://www.lyx.org/" % version
        if self.header[1][0] == '#':
            del self.header[1]

    def read_format(self):
        for line in self.header:
            result = fileformat.match(line)
            if result:
                return self.lyxformat(result.group(1))
        else:
            self.error("Invalid LyX File.")
        return None


    def set_format(self):
        if self.format <= 217:
            format = str(float(format)/100)
        else:
            format = str(self.format)
        i = find_token(self.header, "\\lyxformat", 0)
        self.header[i] = "\\lyxformat %s" % format


    def chain(self):
        """ This is where all the decisions related with the convertion are taken"""

        self.start =  self.format
        format = self.format
        correct_version = 0

        for rel in format_relation:
            if self.initial_version in rel[2]:
                if format in rel[1]:
                    initial_step = rel[0]
                    correct_version = 1
                    break

        if not correct_version:
            if format <= 215:
                self.warning("Version does not match file format, discarding it.")
            for rel in format_relation:
                if format in rel[1]:
                    initial_step = rel[0]
                    break
            else:
                # This should not happen, really.
                self.error("Format not supported.")

        # Find the final step
        for rel in format_relation:
            if self.end_format in rel[1]:
                final_step = rel[0]
                break
        else:
            self.error("Format not supported.")

        # Convertion mode, back or forth
        steps = []
        if (initial_step, self.start) < (final_step, self.end_format):
            mode = "convert"
            first_step = 1
            for step in format_relation:
                if  initial_step <= step[0] <= final_step:
                    if first_step and len(step[1]) == 1:
                        first_step = 0
                        continue
                    steps.append(step[0])
        else:
            mode = "revert"
            relation_format = format_relation
            relation_format.reverse()
            last_step = None

            for step in relation_format:
                if  final_step <= step[0] <= initial_step:
                    steps.append(step[0])
                    last_step = step

            if last_step[1][-1] == self.end_format:
                steps.pop()

        return mode, steps