#!/usr/bin/python
# -*- coding: utf-8 -*-
"""
Playstreamproxy daemon (based on Livestream daemon)
Provides API to ContetSources + stream serving to play via m3u8 playlists
"""

import os, sys, time, re, json
import ConfigParser
import atexit
from signal import SIGTERM

from BaseHTTPServer import HTTPServer, BaseHTTPRequestHandler
from SocketServer import ThreadingMixIn
import time, threading, socket, SocketServer

from urllib import unquote, quote
import urllib,urlparse
import requests

#import cookielib,urllib2
from ContentSources import ContentSources
from sources.SourceBase import stream_type
import util
from util import streamproxy_decode3, streamproxy_encode3

try:
    from requests.packages.urllib3.exceptions import InsecureRequestWarning
    requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
except:
    pass

HOST_NAME = "0.0.0.0"
PORT_NUMBER = 8880
REDIRECT = True
MULTITHREAD = False
WORKERS = 10
KEY = ""
DEBUG = False
DEBUG2 = False

SPLIT_CHAR = "~"
SPLIT_CODE = "%7E"
EQ_CODE = "%3D"
COL_CODE = "%3A"

cunicode = lambda s: s.decode("utf8") if isinstance(s, str) else s
cstr = lambda s: s.encode("utf8") if isinstance(s, unicode) else s
headers2dict = lambda  h: dict([l.strip().split(": ") for l in h.strip().splitlines()])

headers0 = headers2dict("""
User-Agent: GStreamer souphttpsrc libsoup/2.52.2
icy-metadata: 1
""")
headers0_ = headers2dict("""
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36
""")

cur_directory = os.path.dirname(os.path.realpath(__file__))
slinks = {}
sessions = {}

cfg_file = "streams.cfg"
sources = ContentSources("", cfg_file)

config = ConfigParser.ConfigParser()
proxy_cfg_file = os.path.join(cur_directory, "playstreamproxy.cfg")
if not os.path.exists(proxy_cfg_file):
    config.add_section("playstreamproxy")
    config.set("playstreamproxy", "debug", DEBUG)
    config.set("playstreamproxy", "host", HOST_NAME)
    config.set("playstreamproxy", "port", PORT_NUMBER)
    config.set("playstreamproxy", "redirect", REDIRECT)
    config.set("playstreamproxy", "key", KEY)
    config.set("playstreamproxy", "multithread", MULTITHREAD)
    config.set("playstreamproxy", "workers", WORKERS)
    config.set("playstreamproxy", "wsgi", "wsgiref")
    config.write(open(proxy_cfg_file, "w"))
else:
    config.read(proxy_cfg_file)
    DEBUG = config.getboolean("playstreamproxy", "debug")
    HOST_NAME = config.get("playstreamproxy", "host")
    PORT_NUMBER = config.getint("playstreamproxy", "port")
    REDIRECT = config.getboolean("playstreamproxy", "redirect")
    KEY = config.get("playstreamproxy", "key")
    MULTITHREAD = config.getboolean("playstreamproxy", "multithread")
    WORKERS = config.getint("playstreamproxy", "workers")
    pass

class StreamHandler(BaseHTTPRequestHandler):

    def do_HEAD(self):
        print "**get_head"
        self.send_response(200)
        self.send_header("Server", "playstreamproxy")
        if ".m3u8" in self.path.lower():
            ct = "application/vnd.apple.mpegurl"
        elif ".ts" in self.path.lower():
            ct = "video/MP2T"
        elif ".mp4" in self.path.lower():
            ct = "video/mp4"
        else:
            ct = "text/html"
        self.send_header("Content-type", ct)
        self.end_headers()

    def do_GET(self):
        """Respond to a GET request"""
        #
        print "\n\n"+40*"#"+"\nget_url: \n%s" % self.path
        cmd, data, headers, qs = streamproxy_decode3(self.path)
        if KEY:
            key = qs["key"] if "key" in qs else ""
            if key <> KEY:
                print "No key provided"
                #self.send_response(404)
                self.write_error(404)
                return
        if DEBUG:
            print "cmd=%s"%cmd
            print "Original request headers + url headers:"
            print_headers(self.headers.dict)
        self.protocol_version = 'HTTP/1.1'
        try:
            if cmd == "playstream":
                self.fetch_source( self.path)
            elif cmd in ["get_content", "get_streams", "get_info", "is_video", "options_read", "options_write"]:
                if cmd == "get_content":
                    content = sources.get_content(data)
                elif cmd == "get_streams":
                    content = sources.get_streams(data)
                elif cmd == "get_info":
                    content = sources.get_info(data)
                elif cmd == "is_video":
                    content = sources.is_video(data)
                elif cmd == "options_read":
                    content = sources.options_read(data)
                else:
                    content = []
                txt = json.dumps(content)
                self.send_response(200)
                self.send_header("Server", "playstreamproxy")
                self.send_header("Content-type", "application/json")
                self.end_headers()
                self.wfile.write(txt)
                self.wfile.close()
            else:
                self.write_error(404)

        except Exception as e:
            print "Got Exception: ", str(e)
            import traceback
            traceback.print_exc()


    ### Remote server request procedures ###

    def fetch_offline(self):
        print "** Fetch offline"
        self.send_response(200)
        self.send_header("Server", "playstreamproxy")
        self.send_header("Content-type", "video/mp4")
        self.end_headers()
        self.wfile.write(open("offline.mp4", "rb").read())
        #self.wfile.close()

    def redirect_source(self, urlp):
        cmd, data, headers, qs = streamproxy_decode3(urlp)
        streams = sources.get_streams(data)
        if not streams:
            self.write_error(500)  # TODO
            return
        stream = streams[0]
        url = stream["url"]
        headers = stream["headers"] if "headers" in stream else headers0
        self.send_response(307)
        self.send_header("Location", url)
        self.end_headers()


    def fetch_source(self, urlp):
        cmd, data, headers, qs = streamproxy_decode3(urlp)
        if DEBUG:
            print "\n***********************************************************"
            print "fetch_source: \n%s"%urlp
        base_data = hls_base(urlp)
        if DEBUG:
            print "base_data=", base_data
            print "data=", data
        if not base_data in slinks:
            streams = sources.get_streams(data)
            if not streams:
                self.write_error(500)  # TODO
                return
            stream = streams[0]
            url = stream["url"]
            headers = stream["headers"] if "headers" in stream else headers0
            base_url = hls_base2(url)
            if DEBUG: print "New link, base_url=",base_url
            ses = requests.Session()
            ses.trust_env = False
            slinks[base_data] = {"data": data, "urlp":urlp,"url": url, "base_url": base_url,"session":ses}
        else:
            ses = slinks[base_data]["session"]
            if urlp == slinks[base_data]["urlp"]:
                url = slinks[base_data]["url"]
                if DEBUG: print "Existing base link", url
            else:
                url = urlp.replace(base_data, slinks[base_data]["base_url"])
                if DEBUG: print "Existing new link", url
        if REDIRECT:
            print "-->redirect to: " + url
            self.send_response(307)
            self.send_header("Location", url)
            self.end_headers()
            #self.wfile.close()
            return

        headers2 = headers if headers else self.headers.dict
        headers2 = del_headers(headers2, ["host"])
        r = self.get_page_ses(url,ses,True,headers = headers2)
        code = r.status_code
        if not code in (200,206): # TODO 206 apstrāde!
            self.write_error(code)
            return
        if code == 206:
            print "Code=206"
        self.send_response(code)
        #headers2 = del_headers(r.headers, ["Content-Encoding"])
        self.send_headers(r.headers)
        CHUNK_SIZE = 1024 *4
        while True:
            chunk = r.raw.read(CHUNK_SIZE, decode_content=False)
            if not chunk:
                break
            try:
                self.wfile.write(chunk)
            except Exception as e:
                print "Exception: ", str(e)
                self.wfile.close()
                return
        if DEBUG: print "**File downloaded"
        #if "connection" in r.headers and r.headers["connection"] <> "keep-alive":
        self.wfile.close()
        return


    def send_headers(self,headers):
        #if DEBUG:
            #print "**Return headers: "
            #print_headers(headers)
        for h in headers:
            self.send_header(h, headers[h])
        self.end_headers()

    def write_error(self,code):
        print "***Error, code=%s" % code
        self.send_response(code)
        #self.send_headers(r.headers)
        self.wfile.close() # TODO?
        # self.fetch_offline()

    def get_page_ses(self,url,ses,stream=True, headers=None):
        headers= headers if headers else headers0
        ses.headers.update(headers)
        if DEBUG:
            print "\n\n====================================================\n**get_page_ses\n%s"%url
            print "**Server request headers: "
            print_headers(ses.headers)
        r = ses.get(url, stream=stream, verify=False)
        if DEBUG:
            print "**Server response:", r.status_code
            print "**Server response headers: "
            print_headers(r.headers)
        return r

    def get_page(self,url,headers=None):
        if not headers:
            headers = headers0
        if DEBUG:
            print "\n\n====================================================\n**get_page\n%s"%url
            print "**Server request headers: "
            print_headers(headers)
        r = requests.get(url, headers=headers,stream=True)
        if DEBUG:
            print "**Server response:", r.status_code
            print "**Server response headers: "
            print_headers(r.headers)
        return r

    def address_string(self):
        host, port = self.client_address[:2]
        #return socket.getfqdn(host)
        return host

class ThreadedHTTPServer(ThreadingMixIn, HTTPServer):
    """Handle requests in a separate thread."""

def start(host = HOST_NAME, port = PORT_NUMBER, redirect=REDIRECT):
    global REDIRECT
    if redirect:
        REDIRECT = redirect
    httpd = ThreadedHTTPServer((host, port), StreamHandler)
    print time.asctime(), "Server Starts - %s:%s" % (HOST_NAME, PORT_NUMBER)
    try:
        httpd.serve_forever()
    except KeyboardInterrupt:
        pass
    httpd.server_close()
    print time.asctime(), "Server Stops - %s:%s" % (HOST_NAME, PORT_NUMBER)

def start2(host = HOST_NAME, port = PORT_NUMBER, redirect=REDIRECT,workers=WORKERS):
    global REDIRECT
    if redirect:
        REDIRECT = redirect

    print time.asctime(), "Server Starts - %s:%s" % (host, port)
    addr = ('', port)
    sock = socket.socket (socket.AF_INET, socket.SOCK_STREAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    sock.bind(addr)
    sock.listen(5)

    # Launch  listener threads.
    class Thread(threading.Thread):
        def __init__(self, i):
            threading.Thread.__init__(self)
            self.i = i
            self.daemon = True
            self.start()
        def run(self):
            httpd = HTTPServer(addr, StreamHandler, False)

            # Prevent the HTTP server from re-binding every handler.
            # https://stackoverflow.com/questions/46210672/
            httpd.socket = sock
            httpd.server_bind = self.server_close = lambda self: None

            httpd.serve_forever()
    [Thread(i) for i in range(workers)]
    time.sleep(9e5)
    print time.asctime(), "Server Stops - %s:%s" % (HOST_NAME, PORT_NUMBER)

class Daemon:
    """
    A generic daemon class.
    Usage: subclass the Daemon class and override the run() method
    """
    def __init__(self, pidfile, stdin="/dev/null", stdout="/dev/null", stderr="/dev/null"):
        self.stdin = stdin
        self.stdout = stdout
        self.stderr = stderr
        self.pidfile = pidfile

    def daemonize(self):
        """
        do the UNIX double-fork magic, see Stevens' "Advanced
        Programming in the UNIX Environment" for details (ISBN 0201563177)
        http://www.erlenstar.demon.co.uk/unix/faq_2.html#SEC16
        """
        try:
            pid = os.fork()
            if pid > 0:
                # exit first parent
                sys.exit(0)
        except OSError, e:
            sys.stderr.write("fork #1 failed: %d (%s)\n" % (e.errno, e.strerror))
            sys.exit(1)

        # decouple from parent environment
        os.chdir("/")
        os.setsid()
        os.umask(0)

        # do second fork
        try:
            pid = os.fork()
            if pid > 0:
                # exit from second parent
                sys.exit(0)
        except OSError, e:
            sys.stderr.write("fork #2 failed: %d (%s)\n" % (e.errno, e.strerror))
            sys.exit(1)

        # redirect standard file descriptors
        sys.stdout.flush()
        sys.stderr.flush()
        si = file(self.stdin, "r")
        so = file(self.stdout, "a+")
        se = file(self.stderr, "a+", 0)
        os.dup2(si.fileno(), sys.stdin.fileno())
        os.dup2(so.fileno(), sys.stdout.fileno())
        os.dup2(se.fileno(), sys.stderr.fileno())

        # write pidfile
        atexit.register(self.delpid)
        pid = str(os.getpid())
        file(self.pidfile,"w+").write("%s\n" % pid)

    def delpid(self):
        os.remove(self.pidfile)

    def start(self):
        """
        Start the daemon
        """
        # Check for a pidfile to see if the daemon already runs
        try:
            pf = file(self.pidfile,"r")
            pid = int(pf.read().strip())
            pf.close()
        except IOError:
            pid = None

        if pid:
            message = "pidfile %s already exist. Daemon already running?\n"
            sys.stderr.write(message % self.pidfile)
            sys.exit(1)

        # Start the daemon
        self.daemonize()
        self.run()

    def stop(self):
        """
        Stop the daemon
        """
        # Get the pid from the pidfile
        try:
            pf = file(self.pidfile,"r")
            pid = int(pf.read().strip())
            pf.close()
        except IOError:
            pid = None

        if not pid:
            message = "pidfile %s does not exist. Daemon not running?\n"
            sys.stderr.write(message % self.pidfile)
            return # not an error in a restart

        # Try killing the daemon process
        try:
            while 1:
                os.kill(pid, SIGTERM)
                time.sleep(0.1)
        except OSError, err:
            err = str(err)
            if err.find("No such process") > 0:
                if os.path.exists(self.pidfile):
                    os.remove(self.pidfile)
            else:
                print str(err)
                sys.exit(1)

    def restart(self):
        """
        Restart the daemon
        """
        self.stop()
        self.start()

    def run(self):
        """
        You should override this method when you subclass Daemon. It will be called after the process has been
        daemonized by start() or restart().
        """

class ProxyDaemon(Daemon):
    def run(self):
        if MULTITHREAD:
            start2()
        else:
            start()

def print_headers(headers):
    for h in headers:
        print "%s: %s"%(h,headers[h])

def del_headers(headers0,tags):
    headers = headers0.copy()
    for t in tags:
        if t in headers:
            del headers[t]
        if t.lower() in headers:
            del headers[t.lower()]
    return headers

def hls_base(url):
    base = url.split("?")[0]
    base = "/".join(base.split("/")[0:3])+ "/"
    rest = url.replace(base, "")
    return base

def hls_base2(url):
    base = url.split("?")[0]
    base = "/".join(base.split("/")[0:-1])+ "/"
    rest = url.replace(base, "")
    return base


if __name__ == "__main__":
    daemon = ProxyDaemon("/var/run/playstreamproxy.pid")
    if len(sys.argv) == 2:
        if "start" == sys.argv[1]:
            daemon.start()
        elif "stop" == sys.argv[1]:
            daemon.stop()
        elif "restart" == sys.argv[1]:
            daemon.restart()
        elif "manualstart" == sys.argv[1]:
            daemon.run()
        elif "multithread" == sys.argv[1]:
            start2()
        else:
            print "Unknown command"
            sys.exit(2)
        sys.exit(0)
    else:
        print "usage: %s start|stop|restart|manualstart" % sys.argv[0]
        sys.exit(2)