#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""Build a songbook, according to parameters found in a .sb file."""

from subprocess import call
import codecs
import glob
import json
import os.path
import re
import sys

from songbook.files import recursiveFind
from songbook.index import processSXD
from songbook.songs import Song, SongsList
from songbook import __SHAREDIR__


def parseTemplate(template):
    """Return the list of parameters defined in the template."""
    embeddedJsonPattern = re.compile(r"^%%:")
    with open(template) as template_file:
        code = [
                line[3:-1]
                for line
                in template_file
                if embeddedJsonPattern.match(line)
                ]

    data = json.loads(''.join(code))
    parameters = dict()
    for param in data:
        parameters[param["name"]] = param
    return parameters


def toValue(parameter, data):
    if "type" not in parameter:
        return data
    elif parameter["type"] == "stringlist":
        if "join" in parameter:
            joinText = parameter["join"]
        else:
            joinText = ''
        return joinText.join(data)
    elif parameter["type"] == "color":
        return data[1:]
    elif parameter["type"] == "font":
        return data + 'pt'
    elif parameter["type"] == "enum":
        return data
    elif parameter["type"] == "file":
        return data
    elif parameter["type"] == "flag":
        if "join" in parameter:
            joinText = parameter["join"]
        else:
            joinText = ''
        return joinText.join(data)


def formatDeclaration(name, parameter):
    value = ""
    if "default" in parameter:
        value = parameter["default"]
    return (
            '\\def\\set@{name}#1{{\\def\\get{name}{{#1}}}}\n'.format(name=name)
            + formatDefinition(name, toValue(parameter, value))
            )


def formatDefinition(name, value):
    return '\\set@{name}{{{value}}}\n'.format(name=name, value=value)


def clean(basename):
    """Clean (some) temporary files used during compilation.

    Depending of the LaTeX modules used in the template, there may be others
    that are note deleted by this function."""
    generated_extensions = [
            "_auth.sbx",
            "_auth.sxd",
            ".aux",
            ".log",
            ".out",
            ".sxc",
            ".tex",
            "_title.sbx",
            "_title.sxd",
            ]

    for ext in generated_extensions:
        os.unlink(basename + ext)

    return True


def makeTexFile(sb, output):
    """Create the LaTeX file corresponding to the .sb file given in argument."""
    datadir = sb['datadir']
    name = output[:-4]
    template_dir = os.path.join(datadir, 'templates')
    songs = []

    prefixes_tex = ""
    prefixes = []

    authwords_tex = ""
    authwords = {"after": ["by"], "ignore": ["unknown"], "sep": ["and"]}

    # parse the songbook data
    if "template" in sb:
        template = sb["template"]
        del sb["template"]
    else:
        template = os.path.join(__SHAREDIR__, "templates", "default.tmpl")
    if "songs" in sb:
        songs = sb["songs"]
        del sb["songs"]
    if "titleprefixwords" in sb:
        prefixes = sb["titleprefixwords"]
        for prefix in sb["titleprefixwords"]:
            prefixes_tex += "\\titleprefixword{%s}\n" % prefix
        sb["titleprefixwords"] = prefixes_tex
    if "authwords" in sb:
        # Populating default value
        for key in ["after", "sep", "ignore"]:
            if key not in sb["authwords"]:
                sb["authwords"][key] = authwords[key]
        # Processing authwords values
        authwords = sb["authwords"]
        for key in ["after", "sep", "ignore"]:
            for word in authwords[key]:
                if key == "after":
                    authwords_tex += "\\auth%sword{%s}\n" % ("by", word)
                else:
                    authwords_tex += "\\auth%sword{%s}\n" % (key, word)
        sb["authwords"] = authwords_tex
    if "after" in authwords:
        authwords["after"] = [re.compile(r"^.*%s\b(.*)" % after)
                              for after in authwords["after"]]
    if "sep" in authwords:
        authwords["sep"] = [" %s" % sep for sep in authwords["sep"]] + [","]
        authwords["sep"] = [re.compile(r"^(.*)%s (.*)$" % sep)
                            for sep in authwords["sep"]]

    if "lang" not in sb:
        sb["lang"] = "french"
    if "sort" in sb:
        sort = sb["sort"]
        del sb["sort"]
    else:
        sort = [u"by", u"album", u"@title"]
    Song.sort = sort
    Song.prefixes = prefixes
    Song.authwords = authwords

    parameters = parseTemplate(os.path.join(template_dir, template))

    # compute songslist
    if songs == "all":
        songs = [
                os.path.relpath(filename, os.path.join(datadir, 'songs'))
                for filename
                in recursiveFind(os.path.join(datadir, 'songs'), '*.sg')
                ]
    songslist = SongsList(datadir, sb["lang"])
    songslist.append_list(songs)

    sb["languages"] = ",".join(songslist.languages())

    # output relevant fields
    out = codecs.open(output, 'w', 'utf-8')
    out.write('%% This file has been automatically generated, do not edit!\n')
    out.write('\\makeatletter\n')
    # output automatic parameters
    out.write(formatDeclaration("name", {"default": name}))
    out.write(formatDeclaration("songslist", {"type": "stringlist"}))
    # output template parameter command
    for name, parameter in parameters.iteritems():
        out.write(formatDeclaration(name, parameter))
    # output template parameter values
    for name, value in sb.iteritems():
        if name in parameters:
            out.write(formatDefinition(name, toValue(parameters[name], value)))

    if len(songs) > 0:
        out.write(formatDefinition('songslist', songslist.latex()))
    out.write('\\makeatother\n')

    # output template
    commentPattern = re.compile(r"^\s*%")
    with codecs.open(
            os.path.join(template_dir, template), 'r', 'utf-8'
            ) as template_file:
        content = [
                line
                for line
                in template_file
                if not commentPattern.match(line)
                ]

        for index, line in enumerate(content):
            if re.compile("getDataImgDirectory").search(line):
                if os.path.abspath(os.path.join(datadir, "img")).startswith(
                        os.path.abspath(os.path.dirname(output))
                        ):
                    imgdir = os.path.relpath(
                            os.path.join(datadir, "img"),
                            os.path.dirname(output)
                            )
                else:
                    imgdir = os.path.abspath(os.path.join(datadir, "img"))
                line = line.replace("\\getDataImgDirectory", ' {%s/} ' % imgdir)
                content[index] = line

    out.write(u''.join(content))
    out.close()


def buildsongbook(sb, basename):
    """Build a songbook

    Arguments:
    - sb: Python representation of the .sb songbook configuration file.
    - basename: basename of the songbook to be built.
    """

    texFile = basename + ".tex"

    # Make TeX file
    makeTexFile(sb, texFile)

    if not 'TEXINPUTS' in os.environ.keys():
        os.environ['TEXINPUTS'] = ''
    os.environ['TEXINPUTS'] += os.pathsep + os.path.join(__SHAREDIR__, 'latex')
    os.environ['TEXINPUTS'] += os.pathsep + os.path.join(sb['datadir'], 'latex')

    # First pdflatex pass
    if call(["pdflatex", "--shell-escape", texFile]):
        sys.exit(1)

    # Make index
    sxdFiles = glob.glob("%s_*.sxd" % basename)
    for sxdFile in sxdFiles:
        print "processing " + sxdFile
        idx = processSXD(sxdFile)
        indexFile = open(sxdFile[:-3] + "sbx", "w")
        indexFile.write(idx.entriesToStr().encode('utf8'))
        indexFile.close()

    # Second pdflatex pass
    if call(["pdflatex", "--shell-escape", texFile]):
        sys.exit(1)

    # Cleaning
    if not clean(basename):
        sys.exit(1)