###############################################################################
# This file holds the implementations for all the API clients.
#
# If you want to develop a new client, here are some suggestions: Get the fetch
# methods working first, then the push, then the liquidsoap notifier.  You will
# probably want to create a script on your server side to automatically
# schedule a playlist one minute from the current time.
###############################################################################
import sys
import time
import urllib
import urllib2
import logging
import json
import base64
import traceback
from configobj import ConfigObj

AIRTIME_VERSION = "2.5.0"


# TODO : Place these functions in some common module. Right now, media
# monitor uses the same functions and it would be better to reuse them
# instead of copy pasting them around

def to_unicode(obj, encoding='utf-8'):
    if isinstance(obj, basestring):
        if not isinstance(obj, unicode):
            obj = unicode(obj, encoding)
    return obj

def encode_to(obj, encoding='utf-8'):
    if isinstance(obj, unicode):
        obj = obj.encode(encoding)
    return obj

def convert_dict_value_to_utf8(md):
    #list comprehension to convert all values of md to utf-8
    return dict([(item[0], encode_to(item[1], "utf-8")) for item in md.items()])


api_config = {}

# URL to get the version number of the server API
api_config['version_url'] = 'version/api_key/%%api_key%%'
#URL to register a components IP Address with the central web server
api_config['register_component'] = 'register-component/format/json/api_key/%%api_key%%/component/%%component%%'

#media-monitor
api_config['media_setup_url'] = 'media-monitor-setup/format/json/api_key/%%api_key%%'
api_config['upload_recorded'] = 'upload-recorded/format/json/api_key/%%api_key%%/fileid/%%fileid%%/showinstanceid/%%showinstanceid%%'
api_config['update_media_url'] = 'reload-metadata/format/json/api_key/%%api_key%%/mode/%%mode%%'
api_config['list_all_db_files'] = 'list-all-files/format/json/api_key/%%api_key%%/dir_id/%%dir_id%%/all/%%all%%'
api_config['list_all_watched_dirs'] = 'list-all-watched-dirs/format/json/api_key/%%api_key%%'
api_config['add_watched_dir'] = 'add-watched-dir/format/json/api_key/%%api_key%%/path/%%path%%'
api_config['remove_watched_dir'] = 'remove-watched-dir/format/json/api_key/%%api_key%%/path/%%path%%'
api_config['set_storage_dir'] = 'set-storage-dir/format/json/api_key/%%api_key%%/path/%%path%%'
api_config['update_fs_mount'] = 'update-file-system-mount/format/json/api_key/%%api_key%%'
api_config['reload_metadata_group'] = 'reload-metadata-group/format/json/api_key/%%api_key%%'
api_config['handle_watched_dir_missing'] = 'handle-watched-dir-missing/format/json/api_key/%%api_key%%/dir/%%dir%%'
#show-recorder
api_config['show_schedule_url'] = 'recorded-shows/format/json/api_key/%%api_key%%'
api_config['upload_file_url'] = 'upload-file/format/json/api_key/%%api_key%%'
api_config['upload_retries'] = '3'
api_config['upload_wait'] = '60'
#pypo
api_config['export_url'] = 'schedule/api_key/%%api_key%%'
api_config['get_media_url'] = 'get-media/file/%%file%%/api_key/%%api_key%%'
api_config['update_item_url'] = 'notify-schedule-group-play/api_key/%%api_key%%/schedule_id/%%schedule_id%%'
api_config['update_start_playing_url'] = 'notify-media-item-start-play/api_key/%%api_key%%/media_id/%%media_id%%/'
api_config['get_stream_setting'] = 'get-stream-setting/format/json/api_key/%%api_key%%/'
api_config['update_liquidsoap_status'] = 'update-liquidsoap-status/format/json/api_key/%%api_key%%/msg/%%msg%%/stream_id/%%stream_id%%/boot_time/%%boot_time%%'
api_config['update_source_status'] = 'update-source-status/format/json/api_key/%%api_key%%/sourcename/%%sourcename%%/status/%%status%%'
api_config['check_live_stream_auth'] = 'check-live-stream-auth/format/json/api_key/%%api_key%%/username/%%username%%/password/%%password%%/djtype/%%djtype%%'
api_config['get_bootstrap_info'] = 'get-bootstrap-info/format/json/api_key/%%api_key%%'
api_config['get_files_without_replay_gain'] = 'get-files-without-replay-gain/api_key/%%api_key%%/dir_id/%%dir_id%%'
api_config['update_replay_gain_value'] = 'update-replay-gain-value/format/json/api_key/%%api_key%%'
api_config['notify_webstream_data'] = 'notify-webstream-data/api_key/%%api_key%%/media_id/%%media_id%%/format/json'
api_config['notify_liquidsoap_started'] = 'rabbitmq-do-push/api_key/%%api_key%%/format/json'
api_config['get_stream_parameters'] = 'get-stream-parameters/api_key/%%api_key%%/format/json'
api_config['push_stream_stats'] = 'push-stream-stats/api_key/%%api_key%%/format/json'
api_config['update_stream_setting_table'] = 'update-stream-setting-table/api_key/%%api_key%%/format/json'
api_config['get_files_without_silan_value'] = 'get-files-without-silan-value/api_key/%%api_key%%'
api_config['update_cue_values_by_silan'] = 'update-cue-values-by-silan/api_key/%%api_key%%'



################################################################################
# Airtime API Client
################################################################################

class UrlException(Exception): pass

class IncompleteUrl(UrlException):
    def __init__(self, url): self.url = url
    def __str__(self): return "Incomplete url: '%s'" % self.url

class UrlBadParam(UrlException):
    def __init__(self, url, param):
        self.url = url
        self.param = param
    def __str__(self):
        return "Bad param '%s' passed into url: '%s'" % (self.param, self.url)

class ApcUrl(object):
    """ A safe abstraction and testable for filling in parameters in
    api_client.cfg"""
    def __init__(self, base_url): self.base_url = base_url

    def params(self, **params):
        temp_url = self.base_url
        for k, v in params.iteritems():
            wrapped_param = "%%" + k + "%%"
            if wrapped_param in temp_url:
                temp_url = temp_url.replace(wrapped_param, str(v))
            else: raise UrlBadParam(self.base_url, k)
        return ApcUrl(temp_url)

    def url(self):
        if '%%' in self.base_url: raise IncompleteUrl(self.base_url)
        else: return self.base_url

class ApiRequest(object):
    def __init__(self, name, url, logger=None):
        self.name = name
        self.url  = url
        self.__req = None
        if logger is None: self.logger = logging
        else: self.logger = logger

    def __call__(self,_post_data=None, **kwargs):
        final_url = self.url.params(**kwargs).url()
        if _post_data is not None: _post_data = urllib.urlencode(_post_data)
        self.logger.debug(final_url)
        try:
            req = urllib2.Request(final_url, _post_data)
            f = urllib2.urlopen(req)
            content_type = f.info().getheader('Content-Type')
            response = f.read()
        except Exception, e:
            #self.logger.error('Exception: %s', e)
            #self.logger.error("traceback: %s", traceback.format_exc())
            raise

        try:
            if content_type == 'application/json':
                data = json.loads(response)
                return data
            else:
                raise InvalidContentType()
        except Exception:
            #self.logger.error(response)
            #self.logger.error("traceback: %s", traceback.format_exc())
            raise

    def req(self, *args, **kwargs):
        self.__req = lambda : self(*args, **kwargs)
        return self

    def retry(self, n, delay=5):
        """Try to send request n times. If after n times it fails then
        we finally raise exception"""
        for i in range(0,n-1):
            try: return self.__req()
            except Exception: time.sleep(delay)
        return self.__req()

class RequestProvider(object):
    """ Creates the available ApiRequest instance that can be read from
    a config file """
    def __init__(self, cfg):
        self.config = cfg
        self.requests = {}
        if self.config["base_dir"].startswith("/"):
            self.config["base_dir"] = self.config["base_dir"][1:]
        self.url = ApcUrl("http://%s:%s/%s%s/%s" \
            % (self.config["host"], str(self.config["base_port"]),
               self.config["base_dir"], self.config["api_base"],
               '%%action%%'))
        # Now we must discover the possible actions
        actions = dict( (k,v) for k,v in cfg.iteritems() if '%%api_key%%' in v)
        for action_name, action_value in actions.iteritems():
            new_url = self.url.params(action=action_value).params(
                api_key=self.config['api_key'])
            self.requests[action_name] = ApiRequest(action_name, new_url)

    def available_requests(self)    : return self.requests.keys()
    def __contains__(self, request) : return request in self.requests

    def __getattr__(self, attr):
        if attr in self: return self.requests[attr]
        else: return super(RequestProvider, self).__getattribute__(attr)


class AirtimeApiClient(object):
    def __init__(self, logger=None,config_path='/etc/airtime/api_client.cfg'):
        if logger is None: self.logger = logging
        else: self.logger = logger

        # loading config file
        try:
            self.config = ConfigObj(config_path)
            self.config.update(api_config)
            self.services = RequestProvider(self.config)
        except Exception, e:
            self.logger.error('Error loading config file: %s', config_path)
            self.logger.error("traceback: %s", traceback.format_exc())
            sys.exit(1)

    def __get_airtime_version(self):
        try: return self.services.version_url()[u'version']
        except Exception: return -1

    def is_server_compatible(self, verbose=True):
        logger = self.logger
        version = self.__get_airtime_version()
        # logger.info('Airtime version found: ' + str(version))
        if version == -1:
            if (verbose):
                logger.info('Unable to get Airtime version number.\n')
            return False
        elif version[0:3] != AIRTIME_VERSION[0:3]:
            if verbose:
                logger.info('Airtime version found: ' + str(version))
                logger.info('pypo is at version ' + AIRTIME_VERSION +
                    ' and is not compatible with this version of Airtime.\n')
            return False
        else:
            if verbose:
                logger.info('Airtime version: ' + str(version))
                logger.info('pypo is at version ' + AIRTIME_VERSION + ' and is compatible with this version of Airtime.')
            return True


    def get_schedule(self):
        # TODO : properly refactor this routine
        # For now the return type is a little messed up for compatibility reasons
        try: return (True, self.services.export_url())
        except: return (False, None)

    def notify_liquidsoap_started(self):
        try:
            self.services.notify_liquidsoap_started()
        except Exception, e:
            self.logger.error(str(e))

    def notify_media_item_start_playing(self, media_id):
        """ This is a callback from liquidsoap, we use this to notify
        about the currently playing *song*. We get passed a JSON string
        which we handed to liquidsoap in get_liquidsoap_data(). """
        try:
            return self.services.update_start_playing_url(media_id=media_id)
        except Exception, e:
            self.logger.error(str(e))
            return None

    def get_shows_to_record(self):
        try:
            return self.services.show_schedule_url()
        except Exception, e:
            self.logger.error(str(e))
            return None

    def upload_recorded_show(self, data, headers):
        logger = self.logger
        response = ''

        retries = int(self.config["upload_retries"])
        retries_wait = int(self.config["upload_wait"])

        url = self.construct_url("upload_file_url")

        logger.debug(url)

        for i in range(0, retries):
            logger.debug("Upload attempt: %s", i + 1)

            try:
                request = urllib2.Request(url, data, headers)
                response = urllib2.urlopen(request).read().strip()

                logger.info("uploaded show result %s", response)
                break

            except urllib2.HTTPError, e:
                logger.error("Http error code: %s", e.code)
            except urllib2.URLError, e:
                logger.error("Server is down: %s", e.args)
            except Exception, e:
                logger.error("Exception: %s", e)

            #wait some time before next retry
            time.sleep(retries_wait)

        return response

    def check_live_stream_auth(self, username, password, dj_type):
        try:
            return self.services.check_live_stream_auth(
                username=username, password=password, djtype=dj_type)
        except Exception, e:
            self.logger.error(str(e))
            return {}

    def construct_url(self,config_action_key):
        """Constructs the base url for every request"""
        # TODO : Make other methods in this class use this this method.
        if self.config["base_dir"].startswith("/"):
            self.config["base_dir"] = self.config["base_dir"][1:]
        url = "http://%s:%s/%s%s/%s" %  \
            (self.config["host"], str(self.config["base_port"]),
             self.config["base_dir"], self.config["api_base"],
             self.config[config_action_key])
        url = url.replace("%%api_key%%", self.config["api_key"])
        return url

    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def setup_media_monitor(self):
        return self.services.media_setup_url()

    def send_media_monitor_requests(self, action_list, dry=False):
        """
        Send a gang of media monitor events at a time. actions_list is a
        list of dictionaries where every dictionary is representing an
        action. Every action dict must contain a 'mode' key that says
        what kind of action it is and an optional 'is_record' key that
        says whether the show was recorded or not. The value of this key
        does not matter, only if it's present or not.
        """
        # We are assuming that action_list is a list of dictionaries such
        # that every dictionary represents the metadata of a file along
        # with a special mode key that is the action to be executed by the
        # controller.
        valid_actions = []
        # We could get a list of valid_actions in a much shorter way using
        # filter but here we prefer a little more verbosity to help
        # debugging
        for action in action_list:
            if not 'mode' in action:
                self.logger.debug("Warning: Trying to send a request element without a 'mode'")
                self.logger.debug("Here is the the request: '%s'" % str(action) )
            else:
                # We alias the value of is_record to true or false no
                # matter what it is based on if it's absent in the action
                if 'is_record' not in action:
                    action['is_record'] = 0
                valid_actions.append(action)
        # Note that we must prefix every key with: mdX where x is a number
        # Is there a way to format the next line a little better? The
        # parenthesis make the code almost unreadable
        md_list = dict((("md%d" % i), json.dumps(convert_dict_value_to_utf8(md))) \
                for i,md in enumerate(valid_actions))
        # For testing we add the following "dry" parameter to tell the
        # controller not to actually do any changes
        if dry: md_list['dry'] = 1
        self.logger.info("Pumping out %d requests..." % len(valid_actions))
        return self.services.reload_metadata_group(_post_data=md_list)

    #returns a list of all db files for a given directory in JSON format:
    #{"files":["path/to/file1", "path/to/file2"]}
    #Note that these are relative paths to the given directory. The full
    #path is not returned.
    def list_all_db_files(self, dir_id, all_files=True):
        logger = self.logger
        try:
            all_files = u"1" if all_files else u"0"
            response = self.services.list_all_db_files(dir_id=dir_id,
                                                       all=all_files)
        except Exception, e:
            response = {}
            logger.error("Exception: %s", e)
        try:
            return response["files"]
        except KeyError:
            self.logger.error("Could not find index 'files' in dictionary: %s",
                    str(response))
            return []
    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def list_all_watched_dirs(self):
        return self.services.list_all_watched_dirs()

    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def add_watched_dir(self, path):
        return self.services.add_watched_dir(path=base64.b64encode(path))

    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def remove_watched_dir(self, path):
        return self.services.remove_watched_dir(path=base64.b64encode(path))

    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def set_storage_dir(self, path):
        return self.services.set_storage_dir(path=base64.b64encode(path))

    """
    Caller of this method needs to catch any exceptions such as
    ValueError thrown by json.loads or URLError by urllib2.urlopen
    """
    def get_stream_setting(self):
        return self.services.get_stream_setting()

    def register_component(self, component):
        """ Purpose of this method is to contact the server with a "Hey its
        me!" message. This will allow the server to register the component's
        (component = media-monitor, pypo etc.) ip address, and later use it
        to query monit via monit's http service, or download log files via a
        http server. """
        return self.services.register_component(component=component)

    def notify_liquidsoap_status(self, msg, stream_id, time):
        logger = self.logger
        try:
            post_data = {"msg_post": msg}

            #encoded_msg is no longer used server_side!!
            encoded_msg = urllib.quote('dummy')
            self.services.update_liquidsoap_status.req(post_data,
                                            msg=encoded_msg,
                                            stream_id=stream_id,
                                            boot_time=time).retry(5)
        except Exception, e:
            #TODO
            logger.error("Exception: %s", e)

    def notify_source_status(self, sourcename, status):
        try:
            logger = self.logger
            return self.services.update_source_status.req(sourcename=sourcename,
                                                      status=status).retry(5)
        except Exception, e:
            #TODO
            logger.error("Exception: %s", e)

    def get_bootstrap_info(self):
        """ Retrieve infomations needed on bootstrap time """
        return self.services.get_bootstrap_info()

    def get_files_without_replay_gain_value(self, dir_id):
        """
        Download a list of files that need to have their ReplayGain value
        calculated. This list of files is downloaded into a file and the path
        to this file is the return value.
        """
        #http://localhost/api/get-files-without-replay-gain/dir_id/1
        try:
            return self.services.get_files_without_replay_gain(dir_id=dir_id)
        except Exception, e:
            self.logger.error(str(e))
            return []

    def get_files_without_silan_value(self):
        """
        Download a list of files that need to have their cue in/out value
        calculated. This list of files is downloaded into a file and the path
        to this file is the return value.
        """
        try:
            return self.services.get_files_without_silan_value()
        except Exception, e:
            self.logger.error(str(e))
            return []

    def update_replay_gain_values(self, pairs):
        """
        'pairs' is a list of pairs in (x, y), where x is the file's database
        row id and y is the file's replay_gain value in dB
        """
        self.logger.debug(self.services.update_replay_gain_value(
            _post_data={'data': json.dumps(pairs)}))


    def update_cue_values_by_silan(self, pairs):
        """
        'pairs' is a list of pairs in (x, y), where x is the file's database
        row id and y is the file's cue values in dB
        """
        return self.services.update_cue_values_by_silan(_post_data={'data': json.dumps(pairs)})


    def notify_webstream_data(self, data, media_id):
        """
        Update the server with the latest metadata we've received from the
        external webstream
        """
        self.logger.info( self.services.notify_webstream_data.req(
            _post_data={'data':data}, media_id=str(media_id)).retry(5))

    def get_stream_parameters(self):
        response = self.services.get_stream_parameters()
        self.logger.debug(response)
        return response

    def push_stream_stats(self, data):
        # TODO : users of this method should do their own error handling
        response = self.services.push_stream_stats(_post_data={'data': json.dumps(data)})
        return response

    def update_stream_setting_table(self, data):
        try:
            response = self.services.update_stream_setting_table(_post_data={'data': json.dumps(data)})
            return response
        except Exception, e:
            #TODO
            self.logger.error(str(e))


class InvalidContentType(Exception):
    pass
