from __future__ import unicode_literals

import os.path
import re
import subprocess
import sys
import time

from .common import FileDownloader
from ..compat import (
    compat_setenv,
    compat_str,
)
from ..postprocessor.ffmpeg import FFmpegPostProcessor, EXT_TO_OUT_FORMATS
from ..utils import (
    cli_option,
    cli_valueless_option,
    cli_bool_option,
    cli_configuration_args,
    encodeFilename,
    encodeArgument,
    handle_youtubedl_headers,
    check_executable,
    is_outdated_version,
    process_communicate_or_kill,
)


class ExternalFD(FileDownloader):
    def real_download(self, filename, info_dict):
        self.report_destination(filename)
        tmpfilename = self.temp_name(filename)

        try:
            started = time.time()
            retval = self._call_downloader(tmpfilename, info_dict)
        except KeyboardInterrupt:
            if not info_dict.get('is_live'):
                raise
            # Live stream downloading cancellation should be considered as
            # correct and expected termination thus all postprocessing
            # should take place
            retval = 0
            self.to_screen('[%s] Interrupted by user' % self.get_basename())

        if retval == 0:
            status = {
                'filename': filename,
                'status': 'finished',
                'elapsed': time.time() - started,
            }
            if filename != '-':
                fsize = os.path.getsize(encodeFilename(tmpfilename))
                self.to_screen('\r[%s] Downloaded %s bytes' % (self.get_basename(), fsize))
                self.try_rename(tmpfilename, filename)
                status.update({
                    'downloaded_bytes': fsize,
                    'total_bytes': fsize,
                })
            self._hook_progress(status)
            return True
        else:
            self.to_stderr('\n')
            self.report_error('%s exited with code %d' % (
                self.get_basename(), retval))
            return False

    @classmethod
    def get_basename(cls):
        return cls.__name__[:-2].lower()

    @property
    def exe(self):
        return self.params.get('external_downloader')

    @classmethod
    def available(cls):
        return check_executable(cls.get_basename(), [cls.AVAILABLE_OPT])

    @classmethod
    def supports(cls, info_dict):
        return info_dict['protocol'] in ('http', 'https', 'ftp', 'ftps')

    @classmethod
    def can_download(cls, info_dict):
        return cls.available() and cls.supports(info_dict)

    def _option(self, command_option, param):
        return cli_option(self.params, command_option, param)

    def _bool_option(self, command_option, param, true_value='true', false_value='false', separator=None):
        return cli_bool_option(self.params, command_option, param, true_value, false_value, separator)

    def _valueless_option(self, command_option, param, expected_value=True):
        return cli_valueless_option(self.params, command_option, param, expected_value)

    def _configuration_args(self, default=[]):
        return cli_configuration_args(self.params, 'external_downloader_args', default)

    def _call_downloader(self, tmpfilename, info_dict):
        """ Either overwrite this or implement _make_cmd """
        cmd = [encodeArgument(a) for a in self._make_cmd(tmpfilename, info_dict)]

        self._debug_cmd(cmd)

        p = subprocess.Popen(
            cmd, stderr=subprocess.PIPE)
        _, stderr = process_communicate_or_kill(p)
        if p.returncode != 0:
            self.to_stderr(stderr.decode('utf-8', 'replace'))
        return p.returncode


class CurlFD(ExternalFD):
    AVAILABLE_OPT = '-V'

    def _make_cmd(self, tmpfilename, info_dict):
        cmd = [self.exe, '--location', '-o', tmpfilename]
        for key, val in info_dict['http_headers'].items():
            cmd += ['--header', '%s: %s' % (key, val)]
        cmd += self._bool_option('--continue-at', 'continuedl', '-', '0')
        cmd += self._valueless_option('--silent', 'noprogress')
        cmd += self._valueless_option('--verbose', 'verbose')
        cmd += self._option('--limit-rate', 'ratelimit')
        retry = self._option('--retry', 'retries')
        if len(retry) == 2:
            if retry[1] in ('inf', 'infinite'):
                retry[1] = '2147483647'
            cmd += retry
        cmd += self._option('--max-filesize', 'max_filesize')
        cmd += self._option('--interface', 'source_address')
        cmd += self._option('--proxy', 'proxy')
        cmd += self._valueless_option('--insecure', 'nocheckcertificate')
        cmd += self._configuration_args()
        cmd += ['--', info_dict['url']]
        return cmd

    def _call_downloader(self, tmpfilename, info_dict):
        cmd = [encodeArgument(a) for a in self._make_cmd(tmpfilename, info_dict)]

        self._debug_cmd(cmd)

        # curl writes the progress to stderr so don't capture it.
        p = subprocess.Popen(cmd)
        process_communicate_or_kill(p)
        return p.returncode


class AxelFD(ExternalFD):
    AVAILABLE_OPT = '-V'

    def _make_cmd(self, tmpfilename, info_dict):
        cmd = [self.exe, '-o', tmpfilename]
        for key, val in info_dict['http_headers'].items():
            cmd += ['-H', '%s: %s' % (key, val)]
        cmd += self._configuration_args()
        cmd += ['--', info_dict['url']]
        return cmd


class WgetFD(ExternalFD):
    AVAILABLE_OPT = '--version'

    def _make_cmd(self, tmpfilename, info_dict):
        cmd = [self.exe, '-O', tmpfilename, '-nv', '--no-cookies']
        for key, val in info_dict['http_headers'].items():
            cmd += ['--header', '%s: %s' % (key, val)]
        cmd += self._option('--limit-rate', 'ratelimit')
        retry = self._option('--tries', 'retries')
        if len(retry) == 2:
            if retry[1] in ('inf', 'infinite'):
                retry[1] = '0'
            cmd += retry
        cmd += self._option('--bind-address', 'source_address')
        cmd += self._option('--proxy', 'proxy')
        cmd += self._valueless_option('--no-check-certificate', 'nocheckcertificate')
        cmd += self._configuration_args()
        cmd += ['--', info_dict['url']]
        return cmd


class Aria2cFD(ExternalFD):
    AVAILABLE_OPT = '-v'

    def _make_cmd(self, tmpfilename, info_dict):
        cmd = [self.exe, '-c']
        cmd += self._configuration_args([
            '--min-split-size', '1M', '--max-connection-per-server', '4'])
        dn = os.path.dirname(tmpfilename)
        if dn:
            cmd += ['--dir', dn]
        cmd += ['--out', os.path.basename(tmpfilename)]
        for key, val in info_dict['http_headers'].items():
            cmd += ['--header', '%s: %s' % (key, val)]
        cmd += self._option('--interface', 'source_address')
        cmd += self._option('--all-proxy', 'proxy')
        cmd += self._bool_option('--check-certificate', 'nocheckcertificate', 'false', 'true', '=')
        cmd += self._bool_option('--remote-time', 'updatetime', 'true', 'false', '=')
        cmd += ['--', info_dict['url']]
        return cmd


class Aria2pFD(ExternalFD):
    ''' Aria2pFD class
    This class support to use aria2p as downloader.
    (Aria2p, a command-line tool and Python library to interact with an aria2c daemon process
    through JSON-RPC.)
    It can help you to get download progress more easily.
    To use aria2p as downloader, you need to install aria2c and aria2p, aria2p can download with pip.
    Then run aria2c in the background and enable with the --enable-rpc option.
    '''
    try:
        import aria2p
        __avail = True
    except ImportError:
        __avail = False

    @classmethod
    def available(cls):
        return cls.__avail

    def _call_downloader(self, tmpfilename, info_dict):
        aria2 = self.aria2p.API(
            self.aria2p.Client(
                host='http://localhost',
                port=6800,
                secret=''
            )
        )

        options = {
            'min-split-size': '1M',
            'max-connection-per-server': 4,
            'auto-file-renaming': 'false',
        }
        options['dir'] = os.path.dirname(tmpfilename) or os.path.abspath('.')
        options['out'] = os.path.basename(tmpfilename)
        options['header'] = []
        for key, val in info_dict['http_headers'].items():
            options['header'].append('{0}: {1}'.format(key, val))
        download = aria2.add_uris([info_dict['url']], options)
        status = {
            'status': 'downloading',
            'tmpfilename': tmpfilename,
        }
        started = time.time()
        while download.status in ['active', 'waiting']:
            download = aria2.get_download(download.gid)
            status.update({
                'downloaded_bytes': download.completed_length,
                'total_bytes': download.total_length,
                'elapsed': time.time() - started,
                'eta': download.eta.total_seconds(),
                'speed': download.download_speed,
            })
            self._hook_progress(status)
            time.sleep(.5)
        return download.status != 'complete'


class HttpieFD(ExternalFD):
    @classmethod
    def available(cls):
        return check_executable('http', ['--version'])

    def _make_cmd(self, tmpfilename, info_dict):
        cmd = ['http', '--download', '--output', tmpfilename, info_dict['url']]
        for key, val in info_dict['http_headers'].items():
            cmd += ['%s:%s' % (key, val)]
        return cmd


class FFmpegFD(ExternalFD):
    @classmethod
    def supports(cls, info_dict):
        return info_dict['protocol'] in ('http', 'https', 'ftp', 'ftps', 'm3u8', 'rtsp', 'rtmp', 'mms', 'http_dash_segments')

    @classmethod
    def available(cls):
        return FFmpegPostProcessor().available

    def _call_downloader(self, tmpfilename, info_dict):
        url = info_dict['url']
        ffpp = FFmpegPostProcessor(downloader=self)
        if not ffpp.available:
            self.report_error('m3u8 download detected but ffmpeg or avconv could not be found. Please install one.')
            return False
        ffpp.check_version()

        args = [ffpp.executable, '-y']

        for log_level in ('quiet', 'verbose'):
            if self.params.get(log_level, False):
                args += ['-loglevel', log_level]
                break

        seekable = info_dict.get('_seekable')
        if seekable is not None:
            # setting -seekable prevents ffmpeg from guessing if the server
            # supports seeking(by adding the header `Range: bytes=0-`), which
            # can cause problems in some cases
            # https://github.com/ytdl-org/youtube-dl/issues/11800#issuecomment-275037127
            # http://trac.ffmpeg.org/ticket/6125#comment:10
            args += ['-seekable', '1' if seekable else '0']

        args += self._configuration_args()

        # start_time = info_dict.get('start_time') or 0
        # if start_time:
        #     args += ['-ss', compat_str(start_time)]
        # end_time = info_dict.get('end_time')
        # if end_time:
        #     args += ['-t', compat_str(end_time - start_time)]

        if info_dict['http_headers'] and re.match(r'^https?://', url):
            # Trailing \r\n after each HTTP header is important to prevent warning from ffmpeg/avconv:
            # [http @ 00000000003d2fa0] No trailing CRLF found in HTTP header.
            headers = handle_youtubedl_headers(info_dict['http_headers'])
            args += [
                '-headers',
                ''.join('%s: %s\r\n' % (key, val) for key, val in headers.items())]

        env = None
        proxy = self.params.get('proxy')
        if proxy:
            if not re.match(r'^[\da-zA-Z]+://', proxy):
                proxy = 'http://%s' % proxy

            if proxy.startswith('socks'):
                self.report_warning(
                    '%s does not support SOCKS proxies. Downloading is likely to fail. '
                    'Consider adding --hls-prefer-native to your command.' % self.get_basename())

            # Since December 2015 ffmpeg supports -http_proxy option (see
            # http://git.videolan.org/?p=ffmpeg.git;a=commit;h=b4eb1f29ebddd60c41a2eb39f5af701e38e0d3fd)
            # We could switch to the following code if we are able to detect version properly
            # args += ['-http_proxy', proxy]
            env = os.environ.copy()
            compat_setenv('HTTP_PROXY', proxy, env=env)
            compat_setenv('http_proxy', proxy, env=env)

        protocol = info_dict.get('protocol')

        if protocol == 'rtmp':
            player_url = info_dict.get('player_url')
            page_url = info_dict.get('page_url')
            app = info_dict.get('app')
            play_path = info_dict.get('play_path')
            tc_url = info_dict.get('tc_url')
            flash_version = info_dict.get('flash_version')
            live = info_dict.get('rtmp_live', False)
            conn = info_dict.get('rtmp_conn')
            if player_url is not None:
                args += ['-rtmp_swfverify', player_url]
            if page_url is not None:
                args += ['-rtmp_pageurl', page_url]
            if app is not None:
                args += ['-rtmp_app', app]
            if play_path is not None:
                args += ['-rtmp_playpath', play_path]
            if tc_url is not None:
                args += ['-rtmp_tcurl', tc_url]
            if flash_version is not None:
                args += ['-rtmp_flashver', flash_version]
            if live:
                args += ['-rtmp_live', 'live']
            if isinstance(conn, list):
                for entry in conn:
                    args += ['-rtmp_conn', entry]
            elif isinstance(conn, compat_str):
                args += ['-rtmp_conn', conn]

        args += ['-i', url, '-c', 'copy']

        if self.params.get('test', False):
            args += ['-fs', compat_str(self._TEST_FILE_SIZE)]

        if protocol in ('m3u8', 'm3u8_native'):
            if self.params.get('hls_use_mpegts', False) or tmpfilename == '-':
                args += ['-f', 'mpegts']
            else:
                args += ['-f', 'mp4']
                if (ffpp.basename == 'ffmpeg' and is_outdated_version(ffpp._versions['ffmpeg'], '3.2', False)) and (not info_dict.get('acodec') or info_dict['acodec'].split('.')[0] in ('aac', 'mp4a')):
                    args += ['-bsf:a', 'aac_adtstoasc']
        elif protocol == 'rtmp':
            args += ['-f', 'flv']
        else:
            args += ['-f', EXT_TO_OUT_FORMATS.get(info_dict['ext'], info_dict['ext'])]

        args = [encodeArgument(opt) for opt in args]
        args.append(encodeFilename(ffpp._ffmpeg_filename_argument(tmpfilename), True))

        self._debug_cmd(args)

        proc = subprocess.Popen(args, stdin=subprocess.PIPE, env=env)
        try:
            retval = proc.wait()
        except BaseException as e:
            # subprocess.run would send the SIGKILL signal to ffmpeg and the
            # mp4 file couldn't be played, but if we ask ffmpeg to quit it
            # produces a file that is playable (this is mostly useful for live
            # streams). Note that Windows is not affected and produces playable
            # files (see https://github.com/ytdl-org/youtube-dl/issues/8300).
            if isinstance(e, KeyboardInterrupt) and sys.platform != 'win32':
                process_communicate_or_kill(proc, b'q')
            else:
                proc.kill()
                proc.wait()
            raise
        return retval


class AVconvFD(FFmpegFD):
    pass


_BY_NAME = dict(
    (klass.get_basename(), klass)
    for name, klass in globals().items()
    if name.endswith('FD') and name != 'ExternalFD'
)


def list_external_downloaders():
    return sorted(_BY_NAME.keys())


def get_external_downloader(external_downloader):
    """ Given the name of the executable, see whether we support the given
        downloader . """
    # Drop .exe extension on Windows
    bn = os.path.splitext(os.path.basename(external_downloader))[0]
    return _BY_NAME[bn]
