#!/usr/bin/env python3

# Copyright (c) 2011 by Virtuous Flame
# Based BOOSTER 1.01 CSO Compressor
# Adapted for codestation's ZSO format
#
# GNU General Public Licence (GPL)
#
# 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
#

__author__ = "Virtuous Flame"
__license__ = "GPL"
__version__ = "2.0"

import sys
import os

import lz4.block
from struct import pack, unpack
from multiprocessing import Pool
from getopt import gnu_getopt, GetoptError

ZISO_MAGIC = 0x4F53495A
DEFAULT_ALIGN = 0
DEFAULT_BLOCK_SIZE = 0x800
COMPRESS_THREHOLD = 95
DEFAULT_PADDING = br'X'

MP = False
MP_NR = 1024 * 16


def hexdump(data):
    for i in data:
        print("0x%02X" % ((ord(i))))
    print("")


def lz4_compress(plain, level=12):
    mode = "high_compression" if level > 1 else "default"
    return lz4.block.compress(plain, mode=mode, compression=level, store_size=False)


def lz4_compress_mp(i):
    plain = i[0]
    level = i[1]
    mode = "high_compression" if level > 1 else "default"
    return lz4.block.compress(plain, mode=mode, compression=level, store_size=False)


def lz4_decompress(compressed, block_size):
    decompressed = None
    while True:
        try:
            decompressed = lz4.block.decompress(
                compressed, uncompressed_size=block_size)
            break
        except lz4.block.LZ4BlockError:
            compressed = compressed[:-1]
    return decompressed


def usage():
    print("Usage: ziso [-c level] [-m] [-t percent] [-h] infile outfile")
    print("  -c level: 1-12 compress ISO to ZSO, 1 for standard compression, >1 for high compression")
    print("              0 decompress ZSO to ISO (12 by default)")
    print("  -b size:  2048-8192, specify block size (2048 by default)")
    print("  -m Use multiprocessing acceleration for compressing")
    print("  -t percent Compression Threshold (1-100)")
    print("  -a align Padding alignment 0=small/slow 6=fast/large")
    print("  -p pad Padding byte")
    print("  -h this help")


def open_input_output(fname_in, fname_out):
    try:
        fin = open(fname_in, "rb")
    except IOError:
        print("Can't open %s" % (fname_in))
        sys.exit(-1)

    try:
        fout = open(fname_out, "wb")
    except IOError:
        print("Can't create %s" % (fname_out))
        sys.exit(-1)

    return fin, fout


def seek_and_read(fin, offset, size):
    fin.seek(offset)
    return fin.read(size)


def read_zso_header(fin):
    # ZSO header has 0x18 bytes
    data = seek_and_read(fin, 0, 0x18)
    magic, header_size, total_bytes, block_size, ver, align = unpack(
        'IIQIbbxx', data)
    return magic, header_size, total_bytes, block_size, ver, align


def generate_zso_header(magic, header_size, total_bytes, block_size, ver, align):
    data = pack('IIQIbbxx', magic, header_size,
                total_bytes, block_size, ver, align)
    return data


def show_zso_info(fname_in, fname_out, total_bytes, block_size, total_block, ver, align):
    print("Decompress '%s' to '%s'" % (fname_in, fname_out))
    print("Total File Size %ld bytes" % (total_bytes))
    print("block size      %d  bytes" % (block_size))
    print("total blocks    %d  blocks" % (total_block))
    print("index align     %d" % (align))
    print("version         %d" % (ver))


def decompress_zso(fname_in, fname_out):
    fin, fout = open_input_output(fname_in, fname_out)
    magic, header_size, total_bytes, block_size, ver, align = read_zso_header(
        fin)

    if magic != ZISO_MAGIC or block_size == 0 or total_bytes == 0 or header_size != 24 or ver > 1:
        print("ziso file format error")
        return -1

    total_block = total_bytes // block_size
    index_buf = []

    for _ in range(total_block + 1):
        index_buf.append(unpack('I', fin.read(4))[0])

    show_zso_info(fname_in, fname_out, total_bytes,
                  block_size, total_block, ver, align)

    block = 0
    percent_period = total_block/100
    percent_cnt = 0

    while block < total_block:
        percent_cnt += 1
        if percent_cnt >= percent_period and percent_period != 0:
            percent_cnt = 0
            print("decompress %d%%\r" %
                  (block / percent_period), file=sys.stderr, end='\r')

        index = index_buf[block]
        plain = index & 0x80000000
        index &= 0x7fffffff
        read_pos = index << (align)

        if plain:
            read_size = block_size
        else:
            index2 = index_buf[block+1] & 0x7fffffff
            # Have to read more bytes if align was set
            read_size = (index2-index) << (align)
            if block == total_block - 1:
                read_size = total_bytes - read_pos

        zso_data = seek_and_read(fin, read_pos, read_size)

        if plain:
            dec_data = zso_data
        else:
            try:
                dec_data = lz4_decompress(zso_data, block_size)

            except Exception as e:
                print("%d block: 0x%08X %d %s" %
                      (block, read_pos, read_size, e))
                sys.exit(-1)

        if (len(dec_data) != block_size):
            print("%d block: 0x%08X %d" %
                  (block, read_pos, read_size))
            sys.exit(-1)

        fout.write(dec_data)
        block += 1

    fin.close()
    fout.close()
    print("ziso decompress completed")


def show_comp_info(fname_in, fname_out, total_bytes, block_size, ver, align, level):
    print("Compress '%s' to '%s'" % (fname_in, fname_out))
    print("Total File Size %ld bytes" % (total_bytes))
    print("block size      %d  bytes" % (block_size))
    print("index align     %d" % (1 << align))
    print("compress level  %d" % (level))
    print("version         %d" % (ver))
    if MP:
        print("multiprocessing %s" % (MP))


def set_align(fout, write_pos, align):
    if write_pos % (1 << align):
        align_len = (1 << align) - write_pos % (1 << align)
        fout.write(DEFAULT_PADDING * align_len)
        write_pos += align_len

    return write_pos


def compress_zso(fname_in, fname_out, level, bsize):
    fin, fout = open_input_output(fname_in, fname_out)
    fin.seek(0, os.SEEK_END)
    total_bytes = fin.tell()
    fin.seek(0)

    magic, header_size, block_size, ver, align = ZISO_MAGIC, 0x18, bsize, 1, DEFAULT_ALIGN

    # We have to use alignment on any ZSO files which > 2GB, for MSB bit of index as the plain indicator
    # If we don't then the index can be larger than 2GB, which its plain indicator was improperly set
    align = total_bytes // 2 ** 31

    header = generate_zso_header(
        magic, header_size, total_bytes, block_size, ver, align)
    fout.write(header)

    total_block = total_bytes // block_size
    index_buf = [0 for i in range(total_block + 1)]

    fout.write(b"\x00\x00\x00\x00" * len(index_buf))
    show_comp_info(fname_in, fname_out, total_bytes, block_size, ver, align, level)

    write_pos = fout.tell()
    percent_period = total_block/100
    percent_cnt = 0

    if MP:
        pool = Pool()

    block = 0
    while block < total_block:
        if MP:
            percent_cnt += min(total_block - block, MP_NR)
        else:
            percent_cnt += 1

        if percent_cnt >= percent_period and percent_period != 0:
            percent_cnt = 0

            if block == 0:
                print("compress %3d%% avarage rate %3d%%\r" % (
                    block / percent_period, 0), file=sys.stderr, end='\r')
            else:
                print("compress %3d%% avarage rate %3d%%\r" % (
                    block / percent_period, 100*write_pos/(block*block_size)), file=sys.stderr, end='\r')

        if MP:
            iso_data = [(fin.read(block_size), level)
                        for i in range(min(total_block - block, MP_NR))]
            zso_data_all = pool.map_async(
                lz4_compress_mp, iso_data).get(9999999)

            for i, zso_data in enumerate(zso_data_all):
                write_pos = set_align(fout, write_pos, align)
                index_buf[block] = write_pos >> align

                if 100 * len(zso_data) / len(iso_data[i][0]) >= min(COMPRESS_THREHOLD, 100):
                    zso_data = iso_data[i][0]
                    index_buf[block] |= 0x80000000  # Mark as plain
                elif index_buf[block] & 0x80000000:
                    print(
                        "Align error, you have to increase align by 1 or OPL won't be able to read offset above 2 ** 31 bytes")
                    sys.exit(1)

                fout.write(zso_data)
                write_pos += len(zso_data)
                block += 1
        else:
            iso_data = fin.read(block_size)

            try:
                zso_data = lz4_compress(iso_data, level)
            except Exception as e:
                print("%d block: %s" % (block, e))
                sys.exit(-1)

            write_pos = set_align(fout, write_pos, align)
            index_buf[block] = write_pos >> align

            if 100 * len(zso_data) / len(iso_data) >= COMPRESS_THREHOLD:
                zso_data = iso_data
                index_buf[block] |= 0x80000000  # Mark as plain
            elif index_buf[block] & 0x80000000:
                print(
                    "Align error, you have to increase align by 1 or CFW won't be able to read offset above 2 ** 31 bytes")
                sys.exit(1)

            fout.write(zso_data)
            write_pos += len(zso_data)
            block += 1

    # Last position (total size)
    index_buf[block] = write_pos >> align

    # Update index block
    fout.seek(len(header))
    for i in index_buf:
        idx = pack('I', i)
        fout.write(idx)

    print("ziso compress completed , total size = %8d bytes , rate %d%%" %
          (write_pos, (write_pos*100/total_bytes)))

    fin.close()
    fout.close()


def parse_args():
    global MP, COMPRESS_THREHOLD, DEFAULT_PADDING, DEFAULT_ALIGN

    if len(sys.argv) < 2:
        usage()
        sys.exit(-1)

    try:
        optlist, args = gnu_getopt(sys.argv, "c:b:mt:a:p:h")
    except GetoptError as err:
        print(str(err))
        usage()
        sys.exit(-1)

    level = 12
    bsize = DEFAULT_BLOCK_SIZE
    MP = True

    for o, a in optlist:
        if o == '-c':
            level = int(a)
        elif o == '-b':
            bsize = int(a)
        elif o == '-m':
            MP = True
        elif o == '-t':
            COMPRESS_THREHOLD = min(int(a), 100)
        elif o == '-a':
            DEFAULT_ALIGN = int(a)
        elif o == '-p':
            DEFAULT_PADDING = bytes(a[0], encoding='utf8')
        elif o == '-h':
            usage()
            sys.exit(0)

    try:
        fname_in, fname_out = args[1:3]
    except ValueError as err:
        print("You have to specify input/output filename: %s", err)
        sys.exit(-1)

    if bsize%2048 != 0:
        print("Error, invalid block size. Must be multiple of 2048.")
        sys.exit(-1)

    return level, bsize, fname_in, fname_out


def load_sector_table(sector_table_fn, total_block, default_level=9):
    # In future we will support NC
    sectors = [default_level for i in range(total_block)]

    with open(sector_table_fn) as f:
        for line in f:
            line = line.strip()
            a = line.split(":")

            if len(a) < 2:
                raise ValueError("Invalid line founded: %s" % (line))

            if -1 == a[0].find("-"):
                try:
                    sector, level = int(a[0]), int(a[1])
                except ValueError:
                    raise ValueError("Invalid line founded: %s" % (line))
                if level < 1 or level > 9:
                    raise ValueError("Invalid line founded: %s" % (line))
                sectors[sector] = level
            else:
                b = a[0].split("-")
                try:
                    start, end, level = int(b[0]), int(b[1]), int(a[1])
                except ValueError:
                    raise ValueError("Invalid line founded: %s" % (line))
                i = start
                while i < end:
                    sectors[i] = level
                    i += 1

    return sectors


def main():
    print("ziso-python %s by %s" % (__version__, __author__))
    level, bsize, fname_in, fname_out = parse_args()

    if level == 0:
        decompress_zso(fname_in, fname_out)
    else:
        compress_zso(fname_in, fname_out, level, bsize)


PROFILE = False

if __name__ == "__main__":
    if PROFILE:
        import cProfile
        cProfile.run("main()")
    else:
        main()