import http.server
import json
from mec_database import mec_database

# This class will handles any incoming request from the browser
class myHandler(http.server.BaseHTTPRequestHandler):
    __db__ = mec_database()

    # Handler for the GET requests
    def do_GET(self):
        print(">>> do_GET: ", self.path)
        self.protocol_version = self.request_version
        # Check HTTP end_headers
        if self.__check_http_headers__() == False:
            resp = "{\"problemDetails\": {\t\"type\": \"Bad Request\",\t\"title\": \"N/A\",\t\"status\": 400,\t\"detail\": \"Wrong headers\",\t\"instance\": \"N/A\"}}"
            self.send_response(400, 'Bad Request')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', "application/problem+json")
            l = len(resp)
            self.send_header('Content-Length', str(l))
            self.end_headers()
            self.wfile.write(bytes(resp, 'utf-8'))
            return

        resp, content_type = self.__process__()
        print("do_GET: resp= ", resp, ", Content_Type= ", content_type)
        if (resp == None):
            self.send_response(404, 'Not Found')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', content_type)
            self.send_header('Content-Length', '0')
            self.end_headers()
        else:
            if resp.find('Not Found') != -1:
                self.send_response(404, 'Not Found')
            elif resp.find('Forbidden') != -1:
                self.send_response(403, 'Forbidden')
            elif resp.find('Bad Request') != -1:
                self.send_response(400, 'Bad Request')
            else:
                self.send_response(200, 'OK')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', content_type)
            l = len(resp)
            self.send_header('Content-Length', str(l))
            self.end_headers()
            self.wfile.write(bytes(resp, 'utf-8'))
    # End of do_GET

    # Handler for the POST requests
    def do_POST(self):
        print(">>> do_POST: ", self.path)
        self.protocol_version = self.request_version
        # Check HTTP end_headers
        if self.__check_http_headers__() == False:
            resp = "{\"problemDetails\": {\t\"type\": \"Bad Request\",\t\"title\": \"N/A\",\t\"status\": 400,\t\"detail\": \"Wrong headers\",\t\"instance\": \"N/A\"}}"
            self.protocol_version = self.request_version
            self.send_response(400, 'Bad Request')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', "application/problem+json")
            l = len(resp)
            self.send_header('Content-Length', str(l))
            self.end_headers()
            self.wfile.write(bytes(resp, 'utf-8'))
            return

        resp, content_type = self.__process__()
        print("do_POST: resp= ", resp, ", Content_Type= ", content_type)
        if (resp == None):
            self.send_response(404, 'Not Found')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', content_type)
            self.send_header('Content-Length', '0')
            self.end_headers()
        else:
            if resp.find('Not Found') != -1:
                self.send_response(404, 'Not Found')
            elif resp.find('Forbidden') != -1:
                self.send_response(403, 'Forbidden')
            elif resp.find('Bad Request') != -1:
                self.send_response(400, 'Bad Request')
            else:
                self.send_response(200, 'OK')
            self.send_header('Host', self.headers.get('Host'))
            self.send_header('Content-Type', content_type)
            self.send_header('Authorization', self.headers.get('Authorization'))
            self.send_header('Content-Type', content_type)
            l = len(resp)
            self.send_header('Content-Length', str(l))
            self.end_headers()
            self.wfile.write(bytes(resp, 'utf-8'))
    # End of do_POST

    # Check HTTP headers
    def __check_http_headers__(self):
        print (">>> __check_http_headers__")
        result = True
        host = self.headers.get('Host')
        if host == None:
            print("__check_http_headers__: Failed to parse 'Host' header")
            result = False
        content_type = self.headers.get('Content-Type')
        if content_type != "application/json":
            print("__check_http_headers__: Failed to parse 'Content-Type' header")
            result = False
        auth = self.headers.get('Authorization')
        if auth == None:
            print("__check_http_headers__: Failed to parse 'Authorization' header")
            result = False
        return result
    # End of __check_http_headers__

    # Process the request
    def __process__(self):
        s = self.path.split('/')
        print (">>> __process__: ", s)
        if s[1] != 'exampleAPI':
            return None, "application/json"
        # TODO Check HTTP headers
        if s[2] == 'location' and ((s[3] == 'v1') or (s[3] == 'v2')):
            return self.__process__location__api__(s)
        elif s[2] == 'ui' and ((s[3] == 'v1') or (s[3] == 'v2')):
            return self.__process__ue__identity__api__(s)
        elif s[2] == 'rni' and ((s[3] == 'v1') or (s[3] == 'v2')):
            return self.__process__rnis__api__(s)
        elif s[2] == 'bwm' and ((s[3] == 'v1') or (s[3] == 'v2')):
            return self.__process__bwm__api__(s)
        else:
            return None, "application/json"
    # End of __process__

    # Process the LocationAPI request
    def __process__location__api__(self, p_split):
        print (">>> __process__location__api__: ", p_split)
        resp = None
        content_type = "application/json"
        if p_split[4].startswith('users'): # E.g. users?zoneId=zone01
            s = p_split[4].split('?')
            if s.__len__() == 1: # Users list requested
                resp = self.__db__.getSubscriberList(self.path)
            elif s.__len__() == 2: # E.g. zoneId=zone01
                s = s[1].split('=')
                if s[0] == 'zoneId': # Users list into a specific zoneId requested
                    resp = self.__db__.getSubscriberFromZoneId(s[1], self.path)
                elif s[0] == 'address':
                    resp = self.__db__.getSubscriberFromAddress(s[1])
        elif p_split[4] == 'zones':
            if p_split.__len__() == 5:
                s = p_split[4].split('?')
                print("__process__location__api__: ", s)
                if s.__len__() == 1: # A list requested
                    if s[0] == 'zones':
                        resp = self.__db__.getZoneList(self.path)
                    else:
                        resp = "{\"Unsupported zone request\"}"
                elif s.__len__() == 2: # E.g. ?
                    resp = "{\"Unsupported zone request\"}"
                else:
                    resp = "{\"Unsupported " + p_split[4] + " request\"}"
            elif p_split.__len__() == 7:
                if p_split[6] == 'accessPoints':
                    resp = self.__db__.getAccessPointList(p_split[5], self.path)
                else:
                    resp = "{\"Unsupported " + p_split[5] + " request\"}"
            else:
                resp = "{\"Unsupported " + p_split[4] + " request\"}"
        else:
            resp = "{\"Unsupported " + p_split[4] + " request\"}"

        print ("<<< __process__location__api__: ", resp, ", ", content_type)
        return resp, content_type
    # End of __process__location__api__

    # Process the ue_identityAPI request
    def __process__ue__identity__api__(self, p_split):
        print (">>> __process__ue__identity__api__: ", p_split)
        resp = None
        content_type = "application/json"
        if p_split[4] == 'appInst98': # Used for unknown application, e.g. TC_MEC_PLAT_UETAG_003_BI
            resp = "{\"problemDetails\": {\t\"type\": \"Not Authorized\",\t\"title\": \"UEidentityAPI\",\t\"status\": 403,\t\"detail\": \"Forbidden\",\t\"instance\": \"AppInst98\"}}"
        else:
            if p_split[5].startswith('ue_identity_tag_info'): # E.g. ue_identity_tag_info?ueIdentityTag=UeTagA
                s = p_split[5].split('?')
                if s[0] != 'ue_identity_tag_info':
                    resp = "{\"problemDetails\": {\t\"type\": \"Bad Request\",\t\"title\": \"UEidentityAPI\",\t\"status\": 400,\t\"detail\": \"Wrong parameters\",\t\"instance\": \"string\"}}"
                elif s.__len__() == 1: # ue_identity_tag_info, POST
                    # Register/Unregister operation
                    body = None
                    # Extract the body if any
                    content_len = int(self.headers.get('Content-Length'))
                    if (content_len != 0):
                        body = self.rfile.read(content_len)
                        json_msg = self.__decode__json__body__(body)
                        if (json_msg == None):
                            resp = "{\"problemDetails\": {\t\"type\": \"Body processing not supported\",\t\"title\": \"UEidentityAPI\",\t\"status\": 400,\t\"detail\": \"Unknown request\",\t\"instance\": \"string\"}}"
                        else:
                            resp = self.__db__.registerUEidentity(p_split[4], json_msg)
                elif s.__len__() == 2: # E.g. ueIdentityTag=UeTagA
                    s = s[1].split('=')
                    if s[0] == 'ueIdentityTag': # Users list into a specific zoneId requested
                        resp = self.__db__.getUEidentityTagInfo(p_split[4], s[1])
                        if (resp == None):
                            resp = "{\"problemDetails\": {\t\"type\": \"Not Found\",\t\"title\": \"UEidentityAPI\",\t\"status\": 404,\t\"detail\": \"Wrong parameters\",\t\"instance\": \"string\"}}"
                            content_type = "application/problem+json"
        if (resp == None):
            resp = "{\"problemDetails\": {\t\"type\": \"Bad Request\",\t\"title\": \"UEidentityAPI\",\t\"status\": 400,\t\"detail\": \"Wrong parameters\",\t\"instance\": \"string\"}}"
            content_type = "application/problem+json"
        elif resp.find('problemDetails') != -1:
            content_type = "application/problem+json"

        print ("<<< __process__ue__identity__api__: ", resp, ", ", content_type)
        return resp, content_type
    # End of __process__ue__identity__api__

    # Process the RnisAPI request
    def __process__rnis__api__(self, p_split):
        print (">>> __process__rnis__api__: ", p_split)
        resp = None
        content_type = "application/json"
        if p_split[4].startswith('subscriptions'):
            if p_split.__len__() == 6:
                if p_split[5] == '':
                    resp = self.__db__.getSubscriptionLinkList(self.path)
        if (resp == None):
            resp = "{\"problemDetails\": {\t\"type\": \"Not supported\",\t\"title\": \"RnisAPI\",\t\"status\": 400,\t\"detail\": \"Wrong parameters\",\t\"instance\": \"string\"}}"
            content_type = "application/problem+json"

        print ("<<< __process__rnis__api__: ", resp, ", ", content_type)
        return resp, content_type
    # End of __process__rnis__api__

    # Process the BwManagementAPI request
    def __process__bwm__api__(self, p_split):
        print (">>> __process__bwm__api__: ", p_split)
        resp = None
        content_type = "application/json"
        if p_split[4].startswith('bw_allocations'): # E.g. bw_allocation?app_instance_id=InstApp01
            s = p_split[4].split('?')
            if s.__len__() == 1: # ue_identity_tag_info, POST
                # Register/Unregister operation
                body = None
                # Extract the body if any
                content_len = int(self.headers.get('Content-Length'))
                if (content_len != 0):
                    body = self.rfile.read(content_len)
                    json_msg = self.__decode__json__body__(body)
                    if (json_msg == None):
                        resp = "{\"problemDetails\": {\t\"type\": \"Body processing not supported\",\t\"title\": \"BwManagementAPI\",\t\"status\": 400,\t\"detail\": \"Unknown request\",\t\"instance\": \"string\"}}"
                        content_type = "application/problem+json"
                    else:
                        resp = self.__db__.bwAllocation(json_msg)
            elif s.__len__() == 2: # E.g. app_instance_id=InstApp01
                s = s[1].split('=')
                if s[0] == 'app_instance_id':
                    resp = self.__db__.getBwAllocationAppInst(p_split[4], s[1])
        if (resp == None):
            resp = "{\"problemDetails\": {\t\"type\": \"Not supported\",\t\"title\": \"BwManagementAPI\",\t\"status\": 400,\t\"detail\": \"Wrong parameters\",\t\"instance\": \"string\"}}"
            content_type = "application/problem+json"

        print ("<<< __process__bwm__api__: ", resp, ", ", content_type)
        return resp, content_type
    # End of __process__bwm__api__

    # Decode a Json HTTP body message
    def __decode__json__body__(self, p_body):
        json_msg = json.loads(p_body)
        print("__decode__json__body__: ", type(json_msg))
        if ("ueIdentityTags" in json_msg.keys()) == False:
            return None
        return json_msg.get("ueIdentityTags")[0]
    # End of __decode__json__body__

# End of class SimpleHTTPRequestHandler