from flask import request
from flask_restful import Resource, reqparse

from bedrock.knowledge_service import ExternalDatasetService


class BedrockRetrievalApi(Resource):
    # url : <your-endpoint>/retrieval
    def post(self):
        parser = reqparse.RequestParser()
        parser.add_argument("retrieval_setting", nullable=False, required=True, type=dict, location="json")
        parser.add_argument("query", nullable=False, required=True, type=str,)
        parser.add_argument("knowledge_id", nullable=False, required=True, type=str)
        args = parser.parse_args()

        # Authorization check
        auth_header = request.headers.get("Authorization")
        if " " not in auth_header:
            return {
                "error_code": 1001,
                "error_msg": "Invalid Authorization header format. Expected 'Bearer <api-key>' format."
            }, 403
        auth_scheme, auth_token = auth_header.split(None, 1)
        auth_scheme = auth_scheme.lower()
        if auth_scheme != "bearer":
            return {
                "error_code": 1001,
                "error_msg": "Invalid Authorization header format. Expected 'Bearer <api-key>' format."
            }, 403
        if auth_token:
            # process your authorization logic here
            pass

        # Call the knowledge retrieval service
        result = ExternalDatasetService.knowledge_retrieval(
            args["retrieval_setting"], args["query"], args["knowledge_id"]
        )
        return result, 200

import boto3


class ExternalDatasetService:
    @staticmethod
    def knowledge_retrieval(retrieval_setting: dict, query: str, knowledge_id: str):
        # get bedrock client
        client = boto3.client(
            "bedrock-agent-runtime",
            aws_secret_access_key="AWS_SECRET_ACCESS_KEY",
            aws_access_key_id="AWS_ACCESS_KEY_ID",
            # example: us-east-1
            region_name="AWS_REGION_NAME",
        )
        # fetch external knowledge retrieval
        response = client.retrieve(
            knowledgeBaseId=knowledge_id,
            retrievalConfiguration={
                "vectorSearchConfiguration": {"numberOfResults": retrieval_setting.get("top_k"), "overrideSearchType": "HYBRID"}
            },
            retrievalQuery={"text": query},
        )
        # parse response
        results = []
        if response.get("ResponseMetadata") and response.get("ResponseMetadata").get("HTTPStatusCode") == 200:
            if response.get("retrievalResults"):
                retrieval_results = response.get("retrievalResults")
                for retrieval_result in retrieval_results:
                    # filter out results with score less than threshold
                    if retrieval_result.get("score") < retrieval_setting.get("score_threshold", .0):
                        continue
                    result = {
                        "metadata": retrieval_result.get("metadata"),
                        "score": retrieval_result.get("score"),
                        "title": retrieval_result.get("metadata").get("x-amz-bedrock-kb-source-uri"),
                        "content": retrieval_result.get("content").get("text"),
                    }
                    results.append(result)
        return {
            "records": results
        }