# coding: utf-8

import requests
import os
import os.path

class Mastodon:
    """ 
    Super basic but thorough and easy to use mastodon.social 
    api wrapper in python.
        
    If anything is unclear, check the official API docs at
    https://github.com/Gargron/mastodon/wiki/API
        
    Presently, only username-password login is supported, somebody please
    patch in Real Proper OAuth if desired.
        
    KNOWN BUGS: Media api does not work, reason unclear.
    """
    __DEFAULT_BASE_URL = 'https://mastodon.social'
    
    ###
    # Registering apps
    ###
    @staticmethod    
    def create_app(client_name, scopes = ['read', 'write', 'follow'], redirect_uris = None, to_file = None, api_base_url = __DEFAULT_BASE_URL):                 
        """
        Creates a new app with given client_name and scopes (read, write, follow)
        
        Specify redirect_uris if you want users to be redirected to a certain page after authenticating.
        Specify to_file to persist your apps info to a file so you can use them in the constructor.
        Specify api_base_url if you want to register an app on an instance different from the flagship one.
           
        Returns client_id and client_secret.
        """
        request_data = {
            'client_name': client_name,
            'scopes': " ".join(scopes)
        }
        
        if redirect_uris != None:
            request_data['redirect_uris'] = redirect_uris;
        else:
            request_data['redirect_uris'] = 'urn:ietf:wg:oauth:2.0:oob';
        
        response = requests.post(api_base_url + '/api/v1/apps', data = request_data).json()
        
        if to_file != None:
            with open(to_file, 'w') as secret_file:
                secret_file.write(response['client_id'] + '\n')
                secret_file.write(response['client_secret'] + '\n')
        
        return (response['client_id'], response['client_secret'])
    
    ###
    # Authentication, including constructor
    ###
    def __init__(self, client_id, client_secret = None, access_token = None, api_base_url = __DEFAULT_BASE_URL):
        """
        Creates a new API wrapper instance based on the given client_secret and client_id. If you
        give a client_id and it is not a file, you must also give a secret.
           
        You can also directly specify an access_token, directly or as a file.
            
        Specify api_base_url if you wish to talk to an instance other than the flagship one.
        If a file is given as client_id, read client ID and secret from that file
        """
        self.api_base_url = api_base_url
        self.client_id = client_id                      
        self.client_secret = client_secret
        self.access_token = access_token
        
        if os.path.isfile(self.client_id):
            with open(self.client_id, 'r') as secret_file:
                self.client_id = secret_file.readline().rstrip()
                self.client_secret = secret_file.readline().rstrip()
        else:
            if self.client_secret == None:
                raise ValueError('Specified client id directly, but did not supply secret')
                
        if self.access_token != None and os.path.isfile(self.access_token):
            with open(self.access_token, 'r') as token_file:
                self.access_token = token_file.readline().rstrip()
                
    def log_in(self, username, password, scopes = ['read', 'write', 'follow'], to_file = None):
        """
        Logs in and sets access_token to what was returned.
        Can persist access token to file.
        
        Returns the access_token, as well.
        """
        params = self.__generate_params(locals())
        params['client_id'] = self.client_id
        params['client_secret'] = self.client_secret
        params['grant_type'] = 'password'
        params['scope'] = " ".join(scopes)
        
        response = self.__api_request('POST', '/oauth/token', params)      
        self.access_token = response['access_token']
        
        if to_file != None:
            with open(to_file, 'w') as token_file:
                token_file.write(response['access_token'] + '\n')
        
        return response['access_token']
    
    ###
    # Reading data: Timelines
    ##
    def timeline(self, timeline = 'home', max_id = None, since_id = None, limit = None):
        """
        Returns statuses, most recent ones first. Timeline can be home, mentions, public
        or tag/:hashtag
        """
        params = self.__generate_params(locals(), ['timeline'])
        return self.__api_request('GET', '/api/v1/timelines/' + timeline, params)
    
    ###
    # Reading data: Statuses
    ###
    def status(self, id):
        """
        Returns a status.
        """
        return self.__api_request('GET', '/api/v1/statuses/' + str(id))

    def status_context(self, id):
        """
        Returns ancestors and descendants of the status.
        """
        return self.__api_request('GET', '/api/v1/statuses/' + str(id) + '/context')
    
    def status_reblogged_by(self, id):
        """
        Returns a list of users that have reblogged a status.
        """
        return self.__api_request('GET', '/api/v1/statuses/' + str(id) + '/reblogged_by')
    
    def status_favourited_by(self, id):
        """
        Returns a list of users that have favourited a status.
        """
        return self.__api_request('GET', '/api/v1/statuses/' + str(id) + '/favourited_by')
    
    ###
    # Reading data: Accounts
    ###
    def account(self, id):
        """
        Returns account.
        """
        return self.__api_request('GET', '/api/v1/accounts/' + str(id))

    def account_verify_credentials(self):
        """
        Returns authenticated user's account.
        """
        return self.__api_request('GET', '/api/v1/accounts/verify_credentials')
    
    def account_statuses(self, id, max_id = None, since_id = None, limit = None):
        """
        Returns statuses by user. Same options as timeline are permitted.
        """
        params = self.__generate_params(locals(), ['id'])
        return self.__api_request('GET', '/api/v1/accounts/' + str(id) + '/statuses')

    def account_following(self, id):
        """
        Returns users the given user is following.
        """
        return self.__api_request('GET', '/api/v1/accounts/' + str(id) + '/following')

    def account_followers(self, id):
        """
        Returns users the given user is followed by.
        """
        return self.__api_request('GET', '/api/v1/accounts/' + str(id) + '/followers')

    def account_relationships(self, id):
        """
        Returns relationships (following, followed_by, blocking) of the logged in user to 
        a given account. id can be a list.
        """
        params = self.__generate_params(locals())
        return self.__api_request('GET', '/api/v1/accounts/relationships', params)
    
    def account_suggestions(self):
        """
        Returns accounts that the system suggests the authenticated user to follow.
        """
        return self.__api_request('GET', '/api/v1/accounts/suggestions') 

    def account_search(self, q, limit = None):
        """
        Returns matching accounts. Will lookup an account remotely if the search term is 
        in the username@domain format and not yet in the database.
        """
        params = self.__generate_params(locals())
        return self.__api_request('GET', '/api/v1/accounts/search', params)
    
    ###
    # Writing data: Statuses
    ###
    def status_post(self, status, in_reply_to_id = None, media_ids = None):
        """
        Posts a status. Can optionally be in reply to another status and contain
        up to four pieces of media (Uploaded via media_post()).
           
        Returns the new status.
        """
        params = self.__generate_params(locals())
        return self.__api_request('POST', '/api/v1/statuses', params)
    
    def toot(self, status):
        """
        Synonym for status_post that only takes the status text as input.
        """
        return self.status_post(status)
        
    def status_delete(self, id):
        """
        Deletes a status
        """
        return self.__api_request('DELETE', '/api/v1/statuses/' + str(id))

    def status_reblog(self, id):
        """Reblogs a status.
        
        Returns a new status that wraps around the reblogged one."""
        return self.__api_request('POST', '/api/v1/statuses/' + str(id) + "/reblog")

    def status_unreblog(self, id):
        """
        Un-reblogs a status.
        
        Returns the status that used to be reblogged.
        """
        return self.__api_request('POST', '/api/v1/statuses/' + str(id) + "/unreblog")

    def status_favourite(self, id):
        """
        Favourites a status.
        
        Returns the favourited status.
        """
        return self.__api_request('POST', '/api/v1/statuses/' + str(id) + "/favourite")
    
    def status_unfavourite(self, id):
        """Favourites a status.
        
        Returns the un-favourited status.
        """
        return self.__api_request('POST', '/api/v1/statuses/' + str(id) + "/unfavourite")
    
    ###
    # Writing data: Statuses
    ###
    def account_follow(self, id):
        """
        Follows a user.
        
        Returns the updated relationship to the user.
        """
        return self.__api_request('POST', '/api/v1/accounts/' + str(id) + "/follow")
    
    def account_unfollow(self, id):
        """
        Unfollows a user.
        
        Returns the updated relationship to the user.
        """
        return self.__api_request('POST', '/api/v1/accounts/' + str(id) + "/unfollow")
    
    def account_block(self, id):
        """
        Blocks a user.
        
        Returns the updated relationship to the user.
        """
        return self.__api_request('POST', '/api/v1/accounts/' + str(id) + "/block")
    
    def account_unblock(self, id):
        """
        Unblocks a user.
        
        Returns the updated relationship to the user.
        """
        return self.__api_request('POST', '/api/v1/accounts/' + str(id) + "/unblock")

    ###
    # Writing data: Media
    ###
    def media_post(self, media_file):
        """
        Posts an image. media_file can either be image data or
        a file name.
           
        Returns the ID of the media that can then be used in status_post().
        """
        if os.path.isfile(media_file):
            media_file = open(media_file, 'rb')

        return self.__api_request('POST', '/api/v1/media', files = {'file': media_file})
    
    ###
    # Internal helpers, dragons probably
    ###
    def __api_request(self, method, endpoint, params = {}, files = {}):
        """
        Internal API request helper.
        """
        response = None
        headers = None
        
        if self.access_token != None:
            headers = {'Authorization': 'Bearer ' + self.access_token}
        
        if method == 'GET':
            response = requests.get(self.api_base_url + endpoint, data = params, headers = headers, files = files)
        
        if method == 'POST':
            response = requests.post(self.api_base_url + endpoint, data = params, headers = headers, files = files)
            
        if method == 'DELETE':
            response = requests.delete(self.api_base_url + endpoint, data = params, headers = headers, files = files)
        
        if response.status_code == 404:
            raise IOError('Endpoint not found.')
        
        if response.status_code == 500:
            raise IOError('General API problem.')
        
        return response.json()
    
    def __generate_params(self, params, exclude = []):
        """
        Internal named-parameters-to-dict helper.
        """
        params = dict(params)
        
        del params['self']
        param_keys = list(params.keys())
        for key in param_keys:
            if params[key] == None or key in exclude:
                del params[key]
        
        param_keys = list(params.keys())
        for key in param_keys:
            if isinstance(params[key], list):
                params[key + "[]"] = params[key]
                del params[key]
                
        return params