#!/usr/bin/env python

import os, re, struct
import cksum, arclib, fsutil, ndscodes
from ndsheader import NdsHeader

"""The parse_* filenames are ugly hacks and should never be used.  I am
seriously thinking of removing them and using CRC only w/ fallback on
header information (both nds and gba have somewhat wellknown UID's in
the headers."""

def parse_clean_name(filename, extension='',
        group='', region='', number=''):
    filename = filename.replace(extension, '')
    filename = filename.strip('.').strip()
    if number:
        if isinstance(number, int): filename = filename.replace('%04d' % number, '')
        else: filename = filename.replace(number, '')
        filename = filename.strip().strip('-').strip()
    filename = filename.replace('(%s)' % group, '')
    filename = filename.replace('(%s)' % region, '')
    filename = filename.strip()
    return filename

def parse_region(filename):
    """Parse the region out of a meta/file name."""
    rre = re.compile('\((?P<region>('+ndscodes.region_keys+'))\).*?(\((?P<group>[^\)]+)\))?')
    m = rre.search(filename)
    if m and m.groupdict().has_key('region'):
        return m.group('region')
    return ''

def parse_num(filename):
    """Parse the number out of a meta/file name."""
    nre = re.compile(r'^(?P<num>(\d+)|x{4})')
    m = nre.search(filename)
    if m and m.groupdict().has_key('num'):
        try: return int(m.group('num'))
        except: return m.group('num')
    return ''

def parse_group(filename):
    """Parse the release group out of a meta/file name."""
    gre = re.compile('\((?P<region>('+ndscodes.region_keys+'))\).*?(\((?P<group>[^\)]+)\))?')
    m = gre.search(filename)
    if m and m.groupdict().has_key('group'):
        return m.group('group')
    return ''

class Rom:
    def __init__(self, path):
        self.path = fsutil.normalize_path(path)
        self.dirpath = os.path.dirname(path)
        self.filename = os.path.basename(self.path)
        self.number = parse_num(self.filename)
        self.region = parse_region(self.filename)
        self.group = parse_group(self.filename)
        self.extension = fsutil.extension_of(self.filename)
        self.clean_name = parse_clean_name(self.filename, self.extension,
                group=self.group, region=self.region, number=self.number)
        self.name = self.clean_name
        self.crc = None
        self.header = None

    def get_crc_from_header(self):
        # if the file type was 'zip' or 'rar', we can get the
        # crc32 of the file from the header of the zip/rar file
        info = arclib.get_info(self.path, '*.nds')
        if not info: return ''
        return arclib.crc(info[0])

    def get_crc_and_header(self):
        f = self.get_file()
        if f:
            self.crc = cksum.CheckSum(f).getfilecrc()
            f.seek(0)
            self.header = NdsHeader(f)
            f.close()
            del f

    def get_crc(self):
        if self.crc: return self.crc
        if self.extension.lower() in ['zip', 'rar']:
            self.crc = self.get_crc_from_header()
            return self.crc
        f = self.get_file()
        if f:
            self.crc = cksum.CheckSum(f).getfilecrc()
            f.close()
            del f
        return self.crc

    def get_header(self):
        if self.header: return self.header
        f = self.get_file()
        if f:
            self.header = NdsHeader(f)
            f.close()
            del f
        return self.header

    def get_file(self, mode='rb'):
        # NOTE: mode of os.tmpfile() is *always* 'wb'
        if self.extension in ('gba', 'nds'):
            return file(self.path, mode)
        elif self.extension in arclib.supported_extensions:
            return arclib.extract(self.path, '*.nds')[0]
        else:
            print 'unrecognized filetype: %s (%s)' % (self.path, self.extension)
            return False

    def __str__(self):
        s = "rom file \"%s\"\n\tname: %s\n\trelease no.: %s\n\tclean: %s\n\tformat: %s" % (self.filename, self.clean_name, self.number, self.clean_name, self.extension)
        if self.crc: s += "\n\tcrc: %s" % (self.crc)
        return s

    def __repr__(self):
        return "<Rom instance: [%s]>" % self.filename