#!/usr/bin/env python3

import argparse
import binascii
import datetime
import hashlib
import io
import json
import logging
import moth
import os
import platform
import shutil
import tempfile
import zipfile
import random

SEEDFN = "SEED"


def write_kv_pairs(ziphandle, filename, kv):
    """ Write out a sorted map to file
    :param ziphandle: a zipfile object
    :param filename: The filename to write within the zipfile object
    :param kv:  the map to write out
    :return:
    """
    filehandle = io.StringIO()
    for key in sorted(kv.keys()):
        if isinstance(kv[key], list):
            for val in kv[key]:
                filehandle.write("%s %s\n" % (key, val))
        else:
            filehandle.write("%s %s\n" % (key, kv[key]))
    filehandle.seek(0)
    ziphandle.writestr(filename, filehandle.read())


def escape(s):
    return s.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')


def build_category(categorydir, outdir):
    category_seed = random.getrandbits(32)

    categoryname = os.path.basename(categorydir.strip(os.sep))
    zipfilename = os.path.join(outdir, "%s.mb" % categoryname)
    logging.info("Building {} from {}".format(zipfilename, categorydir))

    if os.path.exists(zipfilename):
        # open and gather some state
        existing = zipfile.ZipFile(zipfilename, 'r')
        try:
            category_seed = int(existing.open(SEEDFN).read().strip())
        except Exception:
            pass
        existing.close()
    logging.debug("Using PRNG seed {}".format(category_seed))

    zipfileraw = tempfile.NamedTemporaryFile(delete=False)
    mothball = package(categoryname, categorydir, category_seed)
    shutil.copyfileobj(mothball, zipfileraw)
    zipfileraw.close()
    shutil.move(zipfileraw.name, zipfilename)

def write_metadata(ziphandle, category):
    metadata = {"platform": {}, "moth": {}, "category": {}}
    
    try:
        with open("../VERSION", "r") as infile:
            version = infile.read().strip()
            metadata["moth"]["version"] = version
    except IOError:
        pass

    metadata["category"]["build_time"] = datetime.datetime.now().strftime("%c")
    metadata["category"]["type"] = "catmod" if category.catmod is not None else "traditional"
    metadata["platform"]["arch"] = platform.machine()
    metadata["platform"]["os"] = platform.system()
    metadata["platform"]["version"] = platform.platform()
    metadata["platform"]["python_version"] = platform.python_version()

    ziphandle.writestr("meta.json", json.dumps(metadata))

# Returns a file-like object containing the contents of the new zip file
def package(categoryname, categorydir, seed):
    zfraw = io.BytesIO()
    zf = zipfile.ZipFile(zfraw, 'x')
    zf.writestr("category_seed.txt", str(seed))

    cat = moth.Category(categorydir, seed)
    mapping = {}
    answers = {}
    summary = {}
    for puzzle in cat:
        logging.info("Processing point value {}".format(puzzle.points))

        hashmap = hashlib.sha1(str(seed).encode('utf-8'))
        hashmap.update(str(puzzle.points).encode('utf-8'))
        puzzlehash = hashmap.hexdigest()

        mapping[puzzle.points] = puzzlehash
        answers[puzzle.points] = puzzle.answers
        summary[puzzle.points] = puzzle.summary

        puzzledir = os.path.join("content", puzzlehash)
        for fn, f in puzzle.files.items():
            payload = f.stream.read()
            zf.writestr(os.path.join(puzzledir, fn), payload)

        obj = puzzle.package()
        zf.writestr(os.path.join(puzzledir, 'puzzle.json'), json.dumps(obj))

    write_kv_pairs(zf, 'map.txt', mapping)
    write_kv_pairs(zf, 'answers.txt', answers)
    write_kv_pairs(zf, 'summaries.txt', summary)
    write_metadata(zf, cat)

    # clean up
    zf.close()
    zfraw.seek(0)
    return zfraw


if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Build a category package')
    parser.add_argument('outdir', help='Output directory')
    parser.add_argument('categorydirs', nargs='+', help='Directory of category source')
    args = parser.parse_args()

    logging.basicConfig(level=logging.DEBUG)

    outdir = os.path.abspath(args.outdir)
    for categorydir in args.categorydirs:
        categorydir = os.path.abspath(categorydir)
        build_category(categorydir, outdir)