"""
OpenAPI Schema Creator Module

This module provides functionality to create and customize OpenAPI documentation:
- Custom security schemes (Bearer Auth, API Key)
- Response schemas and examples
- Tag management and descriptions
- Error responses and validation
- Custom documentation extensions
"""

from typing import Any, Dict
from fastapi import FastAPI
from fastapi.routing import APIRoute
from fastapi.openapi.utils import get_openapi

from create_routes import get_all_routers
from config import ApiConfig


class OpenAPISchemaCreator:
    """
    OpenAPI schema creator and customizer for FastAPI applications.
    """

    def __init__(self, app: FastAPI):
        """
        Initialize the OpenAPI schema creator.

        Args:
            app: FastAPI application instance
        """
        self.app = app
        self.cluster = get_all_routers()
        self.safe_endpoint_list = self.cluster.safe_endpoints if hasattr(self.cluster, 'safe_endpoints') else []

    def _create_security_schemes(self) -> Dict[str, Any]:
        """
        Create security scheme definitions.

        Returns:
            Dict[str, Any]: Security scheme configurations
        """
        from ApiLayers.AllConfigs.Token.config import Auth
        return {
            "BearerAuth": {
                "type": "apiKey",
                "in": "header",
                "name": Auth.ACCESS_TOKEN_TAG,
                "description": "Enter: **'Bearer <JWT>'**, where JWT is the access token",
            }
        }

    def _create_common_responses(self) -> Dict[str, Any]:
        """
        Create common response schemas.

        Returns:
            Dict[str, Any]: Common response configurations
        """
        return {
            "401": {
                "description": "Unauthorized - Invalid or missing credentials",
                "content": {
                    "application/json": {
                        "schema": {"$ref": "#/components/schemas/HTTPValidationError"}
                    }
                },
            },
            "403": {
                "description": "Forbidden - Insufficient permissions",
                "content": {
                    "application/json": {
                        "schema": {"$ref": "#/components/schemas/HTTPValidationError"}
                    }
                },
            },
            "422": {
                "description": "Validation Error",
                "content": {
                    "application/json": {
                        "schema": {"$ref": "#/components/schemas/HTTPValidationError"}
                    }
                },
            },
            "500": {
                "description": "Internal Server Error",
                "content": {
                    "application/json": {
                        "schema": {
                            "type": "object",
                            "properties": {
                                "detail": {"type": "string"},
                                "error_code": {"type": "string"},
                            },
                        },
                        "example": {
                            "detail": "Internal server error occurred",
                            "error_code": "INTERNAL_ERROR",
                        },
                    }
                },
            },
        }

    def _process_request_body(
        self, path: str, method: str, schema: Dict[str, Any]
    ) -> None:
        """
        Process request body to include examples from model config.

        Args:
            path: Route path
            method: HTTP method
            schema: OpenAPI schema to modify
        """
        try:
            route_schema = schema["paths"][path][method]
            if "requestBody" in route_schema:
                request_body = route_schema["requestBody"]
                if "content" in request_body:
                    content = request_body["content"]
                    if "application/json" in content:
                        json_content = content["application/json"]
                        if (
                            "schema" in json_content
                            and "$ref" in json_content["schema"]
                        ):
                            ref = json_content["schema"]["$ref"]
                            model_name = ref.split("/")[-1]
                            if model_name in schema["components"]["schemas"]:
                                model_schema = schema["components"]["schemas"][
                                    model_name
                                ]
                                if "example" in model_schema:
                                    json_content["example"] = model_schema["example"]
        except KeyError:
            pass

    def _process_response_examples(
        self, path: str, method: str, schema: Dict[str, Any]
    ) -> None:
        """
        Process response body to include examples from model config.

        Args:
            path: Route path
            method: HTTP method
            schema: OpenAPI schema to modify
        """
        try:
            route_schema = schema["paths"][path][method]
            if "responses" in route_schema:
                responses = route_schema["responses"]
                if "200" in responses:
                    response = responses["200"]
                    if "content" in response:
                        content = response["content"]
                        if "application/json" in content:
                            json_content = content["application/json"]
                            if (
                                "schema" in json_content
                                and "$ref" in json_content["schema"]
                            ):
                                ref = json_content["schema"]["$ref"]
                                model_name = ref.split("/")[-1]
                                if model_name in schema["components"]["schemas"]:
                                    model_schema = schema["components"]["schemas"][
                                        model_name
                                    ]
                                    if "example" in model_schema:
                                        json_content["example"] = model_schema[
                                            "example"
                                        ]
        except KeyError:
            pass

    def configure_route_security(
        self, path: str, method: str, schema: Dict[str, Any]
    ) -> None:
        """
        Configure security requirements for a specific route.

        Args:
            path: Route path
            method: HTTP method
            schema: OpenAPI schema to modify
        """
        if not schema.get("paths", {}).get(path, {}).get(method):
            return

        # Check if endpoint is in safe list
        endpoint_path = f"{path}:{method}"
        if endpoint_path not in [f"{e.URL}:{e.METHOD.lower()}" for e in self.safe_endpoint_list]:
            if "security" not in schema["paths"][path][method]:
                schema["paths"][path][method]["security"] = []
            schema["paths"][path][method]["security"].append(
                {"BearerAuth": []}
            )

    def create_schema(self) -> Dict[str, Any]:
        """
        Create the complete OpenAPI schema.

        Returns:
            Dict[str, Any]: Complete OpenAPI schema
        """
        openapi_schema = get_openapi(
            title=ApiConfig.TITLE,
            description=ApiConfig.DESCRIPTION,
            version="1.1.1",
            routes=self.app.routes,
        )

        # Add security schemes
        if "components" not in openapi_schema:
            openapi_schema["components"] = {}

        openapi_schema["components"]["securitySchemes"] = self._create_security_schemes()
        
        # Configure route security and responses
        for route in self.app.routes:
            if isinstance(route, APIRoute) and route.include_in_schema:
                path = str(route.path)
                methods = [method.lower() for method in route.methods]
                for method in methods:
                    self.configure_route_security(path, method, openapi_schema)

        # Add custom documentation extensions
        openapi_schema["x-documentation"] = {
            "postman_collection": "/docs/postman",
            "swagger_ui": "/docs",
            "redoc": "/redoc",
        }
        return openapi_schema


def create_openapi_schema(app: FastAPI) -> Dict[str, Any]:
    """
    Create OpenAPI schema for a FastAPI application.

    Args:
        app: FastAPI application instance

    Returns:
        Dict[str, Any]: Complete OpenAPI schema
    """
    creator = OpenAPISchemaCreator(app)
    return creator.create_schema()