from __future__ import unicode_literals

import io
import json
import traceback
import hashlib
import os
import subprocess
import sys
import platform
from zipimport import zipimporter

from .compat import compat_realpath
from .utils import encode_compat_str

from .version import __version__


def update_binary(ydl):
    LATEST_URL = 'https://api.github.com/repos/blackjack4494/yt-dlc/releases/latest'

    def sha256sum(path):
        h = hashlib.sha256()
        b = bytearray(128 * 1024)
        mv = memoryview(b)
        with open(os.path.realpath(path), 'rb', buffering=0) as f:
            for n in iter(lambda: f.readinto(mv), 0):
                h.update(mv[:n])
        return h.hexdigest()

    if isinstance(globals().get('__loader__'), zipimporter):
        pass
    elif hasattr(sys, 'frozen'):
        pass
    else:
        return ydl.to_screen('It looks like you installed youtube-dlc with a package manager, pip, setup.py or a tarball. Please use that to update')

    filename = compat_realpath(sys.executable if hasattr(sys, 'frozen') else sys.argv[0])
    build_hash = sha256sum(filename)
    ydl.to_screen('Current Build Hash %s' % build_hash)

    # Download and check versions info
    try:
        latest = ydl._opener.open(LATEST_URL).read().decode('utf-8')
        latest_json = json.loads(latest)
    except Exception:
        if ydl.verbose:
            ydl.to_screen(encode_compat_str(traceback.format_exc()))
        ydl.to_screen('ERROR: can\'t obtain versions info. Please try again later.')
        return ydl.to_screen('Visit https://github.com/blackjack4494/yt-dlc/releases/latest')

    latest_version = latest_json['tag_name']

    def download_sha256sums():
        download_url = ''
        for _ in latest_json['assets']:
            if 'SHA2-256SUMS' in _['name']:
                download_url = _['browser_download_url']
                break
        if download_url:
            return ydl._opener.open(download_url).read().decode('utf-8')
        else:
            ydl.to_screen('ERROR: can\'t obtain SHA256SUMS. Please try again later.')
            return None

    sha256sums = download_sha256sums()
    sha256sums_dict = dict(_.split(':') in sha256sums for _ in sha256sums.split('\n'))
    sha256sums_version = sha256sums_dict.get('version')
    if sha256sums_version:
        if build_hash in sha256sums_dict.values():
            ydl.to_screen('SHA256 checksum successfully validated.')
        if __version__.split('.') >= sha256sums_version.split('.') and __version__.split('.') >= latest_version.split('.'):
            ydl.to_screen('youtube-dlc is up to date (%s)' % __version__)
            return
        else:
            ydl.to_screen('Something is wrong here. Trying to update anyway.')
    else:
        if build_hash in sha256sums_dict.values():
            ydl.to_screen('SHA256 checksum successfully validated.')
        if __version__.split('.') >= latest_version.split('.'):
            ydl.to_screen('youtube-dlc is up to date (%s)' % __version__)
            return

    if not latest_version == sha256sums_version:
        ydl.to_screen('WARNING: available youtube-dlc versions differ. Trying to update anyway.')

    ydl.to_screen('Updating to version ' + latest_version + ' ...')

    version_labels = {
        'zip_3': '',
        'exe_64': '.exe',
        'exe_32': '_x86.exe',
    }

    def get_bin_info(bin_or_exe, version):
        label = version_labels['%s_%s' % (bin_or_exe, version)]
        return next((_ for _ in latest_json['assets'] if _['name'] == 'youtube-dlc%s' % label), {})

    if not os.access(filename, os.W_OK):
        return ydl.to_screen('no write permissions on %s' % filename)

    # PyInstaller
    if hasattr(sys, 'frozen'):
        exe = filename
        directory = os.path.dirname(exe)
        if not os.access(directory, os.W_OK):
            return ydl.to_screen('no write permissions on %s' % directory)
        try:
            if os.path.exists(filename + '.old'):
                os.remove(filename + '.old')
        except (IOError, OSError):
            return ydl.to_screen('unable to remove the old version')

        try:
            arch = platform.architecture()[0][:2]
            url = get_bin_info('exe', arch).get('browser_download_url')
            if not url:
                return ydl.to_screen('unable to fetch updates')
            urlh = ydl._opener.open(url)
            newcontent = urlh.read()
            urlh.close()
        except (IOError, OSError, StopIteration):
            return ydl.to_screen('unable to download latest version')

        try:
            with open(exe + '.new', 'wb') as outf:
                outf.write(newcontent)
        except (IOError, OSError):
            return ydl.to_screen('unable to write the new version')

        expected_sum = sha256sums_dict.get('youtube-dlc%s' % version_labels['%s_%s' % ('exe', arch)])
        if not expected_sum:
            ydl.report_warning('no hash information found for the release')
        elif sha256sum(exe + '.new') != expected_sum:
            ydl.to_screen('unable to verify the new executable')
            try:
                os.remove(exe + '.new')
            except OSError:
                return ydl.to_screen('unable to remove corrupt download')

        try:
            os.rename(exe, exe + '.old')
        except (IOError, OSError):
            return ydl.to_screen('unable to move current version')
        try:
            os.rename(exe + '.new', exe)
        except (IOError, OSError):
            ydl.to_screen('unable to overwrite current version')
            os.rename(exe + '.old', exe)
            return
        try:
            # Continues to run in the background
            subprocess.Popen(
                'ping 127.0.0.1 -n 5 -w 1000 & del /F "%s.old"' % exe,
                shell=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
            ydl.to_screen('Updated youtube-dlc to version %s' % latest_version)
            return True  # Exit app
        except OSError:
            ydl.to_screen('unable to delete old version')

    # Zip unix package
    elif isinstance(globals().get('__loader__'), zipimporter):
        try:
            url = get_bin_info('zip', '3').get('browser_download_url')
            if not url:
                return ydl.to_screen('unable to fetch updates')
            urlh = ydl._opener.open(url)
            newcontent = urlh.read()
            urlh.close()
        except (IOError, OSError, StopIteration):
            return ydl.to_screen('unable to download latest version')

        expected_sum = sha256sums_dict.get('youtube-dlc%s' % version_labels['%s_%s' % ('zip', '3')])
        if not expected_sum:
            ydl.report_warning('no hash information found for the release')
        elif hashlib.sha256(newcontent).hexdigest() != expected_sum:
            return ydl.to_screen('unable to verify the new zip')

        try:
            with open(filename, 'wb') as outf:
                outf.write(newcontent)
        except (IOError, OSError):
            return ydl.to_screen('unable to overwrite current version')

    ydl.to_screen('Updated youtube-dlc to version %s; Restart youtube-dlc to use the new version' % latest_version)


def update_self(to_screen, verbose, opener):
    """Update the program file with the latest version from the repository"""

    UPDATE_URL = 'https://blackjack4494.github.io//update/'
    VERSION_URL = UPDATE_URL + 'LATEST_VERSION'
    JSON_URL = UPDATE_URL + 'versions.json'
    # UPDATES_RSA_KEY = (0x9d60ee4d8f805312fdb15a62f87b95bd66177b91df176765d13514a0f1754bcd2057295c5b6f1d35daa6742c3ffc9a82d3e118861c207995a8031e151d863c9927e304576bc80692bc8e094896fcf11b66f3e29e04e3a71e9a11558558acea1840aec37fc396fb6b65dc81a1c4144e03bd1c011de62e3f1357b327d08426fe93, 65537)

    def sha256sum():
        h = hashlib.sha256()
        b = bytearray(128 * 1024)
        mv = memoryview(b)
        with open(os.path.realpath(sys.executable), 'rb', buffering=0) as f:
            for n in iter(lambda: f.readinto(mv), 0):
                h.update(mv[:n])
        return h.hexdigest()

    to_screen('Current Build Hash %s' % sha256sum())

    if not isinstance(globals().get('__loader__'), zipimporter) and not hasattr(sys, 'frozen'):
        to_screen('It looks like you installed youtube-dlc with a package manager, pip, setup.py or a tarball. Please use that to update.')
        return

    # compiled file.exe can find itself by
    # to_screen(os.path.basename(sys.executable))
    # and path to py or exe
    # to_screen(os.path.realpath(sys.executable))

    # Check if there is a new version
    try:
        newversion = opener.open(VERSION_URL).read().decode('utf-8').strip()
    except Exception:
        if verbose:
            to_screen(encode_compat_str(traceback.format_exc()))
        to_screen('ERROR: can\'t find the current version. Please try again later.')
        to_screen('Visit https://github.com/blackjack4494/yt-dlc/releases/latest')
        return
    if newversion == __version__:
        to_screen('youtube-dlc is up-to-date (' + __version__ + ')')
        return

    # Download and check versions info
    try:
        versions_info = opener.open(JSON_URL).read().decode('utf-8')
        versions_info = json.loads(versions_info)
    except Exception:
        if verbose:
            to_screen(encode_compat_str(traceback.format_exc()))
        to_screen('ERROR: can\'t obtain versions info. Please try again later.')
        to_screen('Visit https://github.com/blackjack4494/yt-dlc/releases/latest')
        return
    if 'signature' not in versions_info:
        to_screen('ERROR: the versions file is not signed or corrupted. Aborting.')
        return
    # signature = versions_info['signature']
    del versions_info['signature']

    version_id = versions_info['latest']

    def version_tuple(version_str):
        return tuple(map(int, version_str.split('.')))
    if version_tuple(__version__) >= version_tuple(version_id):
        to_screen('youtube-dlc is up to date (%s)' % __version__)
        return

    to_screen('Updating to version ' + version_id + ' ...')
    version = versions_info['versions'][version_id]

    print_notes(to_screen, versions_info['versions'])

    # sys.executable is set to the full pathname of the exe-file for py2exe
    # though symlinks are not followed so that we need to do this manually
    # with help of realpath
    filename = compat_realpath(sys.executable if hasattr(sys, 'frozen') else sys.argv[0])

    if not os.access(filename, os.W_OK):
        to_screen('ERROR: no write permissions on %s' % filename)
        return

    # Py2EXE
    if hasattr(sys, 'frozen'):
        exe = filename
        directory = os.path.dirname(exe)
        if not os.access(directory, os.W_OK):
            to_screen('ERROR: no write permissions on %s' % directory)
            return

        try:
            urlh = opener.open(version['exe'][0])
            newcontent = urlh.read()
            urlh.close()
        except (IOError, OSError):
            if verbose:
                to_screen(encode_compat_str(traceback.format_exc()))
            to_screen('ERROR: unable to download latest version')
            to_screen('Visit https://github.com/blackjack4494/yt-dlc/releases/latest')
            return

        newcontent_hash = hashlib.sha256(newcontent).hexdigest()
        if newcontent_hash != version['exe'][1]:
            to_screen('ERROR: the downloaded file hash does not match. Aborting.')
            return

        try:
            with open(exe + '.new', 'wb') as outf:
                outf.write(newcontent)
        except (IOError, OSError):
            if verbose:
                to_screen(encode_compat_str(traceback.format_exc()))
            to_screen('ERROR: unable to write the new version')
            return

        try:
            bat = os.path.join(directory, 'youtube-dlc-updater.bat')
            with io.open(bat, 'w') as batfile:
                batfile.write('''
@echo off
echo Waiting for file handle to be closed ...
ping 127.0.0.1 -n 5 -w 1000 > NUL
move /Y "%s.new" "%s" > NUL
echo Updated youtube-dlc to version %s.
start /b "" cmd /c del "%%~f0"&exit /b"
                \n''' % (exe, exe, version_id))

            subprocess.Popen([bat])  # Continues to run in the background
            return  # Do not show premature success messages
        except (IOError, OSError):
            if verbose:
                to_screen(encode_compat_str(traceback.format_exc()))
            to_screen('ERROR: unable to overwrite current version')
            return

    # Zip unix package
    elif isinstance(globals().get('__loader__'), zipimporter):
        try:
            urlh = opener.open(version['bin'][0])
            newcontent = urlh.read()
            urlh.close()
        except (IOError, OSError):
            if verbose:
                to_screen(encode_compat_str(traceback.format_exc()))
            to_screen('ERROR: unable to download latest version')
            to_screen('Visit https://github.com/blackjack4494/yt-dlc/releases/latest')
            return

        newcontent_hash = hashlib.sha256(newcontent).hexdigest()
        if newcontent_hash != version['bin'][1]:
            to_screen('ERROR: the downloaded file hash does not match. Aborting.')
            return

        try:
            with open(filename, 'wb') as outf:
                outf.write(newcontent)
        except (IOError, OSError):
            if verbose:
                to_screen(encode_compat_str(traceback.format_exc()))
            to_screen('ERROR: unable to overwrite current version')
            return

    to_screen('Updated youtube-dlc. Restart youtube-dlc to use the new version.')


def get_notes(versions, fromVersion):
    notes = []
    for v, vdata in sorted(versions.items()):
        if v > fromVersion:
            notes.extend(vdata.get('notes', []))
    return notes


def print_notes(to_screen, versions, fromVersion=__version__):
    notes = get_notes(versions, fromVersion)
    if notes:
        to_screen('PLEASE NOTE:')
        for note in notes:
            to_screen(note)
