/*
 * ═══════════════════════════════════════════════════════════════════════════════════
 * HTTPREQUESTHANDLER.CPP - HTTP REST API Request Handler Implementation
 * ═══════════════════════════════════════════════════════════════════════════════════
 */

#include "HTTPRequestHandler.hpp"
#include "../CommandHandler/CommandHandler.hpp"
#include "../../ConfigManager/ConfigManager.hpp"
#include "../../Logging/Logging.hpp"

HTTPRequestHandler::HTTPRequestHandler(AsyncWebServer& server,
                                     ConfigManager& configManager)
    : _server(server)
    , _configManager(configManager)
    , _commandHandler(nullptr) {
}

HTTPRequestHandler::~HTTPRequestHandler() {
}

void HTTPRequestHandler::begin() {
    LOG_INFO("HTTPRequestHandler - Initializing HTTP REST API endpoints");

    // POST /api/command - Execute any command
    _server.on("/api/command", HTTP_POST,
        [](AsyncWebServerRequest* request) {
            // This is called when request is complete but body is empty
            request->send(400, "application/json", "{\"error\":\"No body provided\"}");
        },
        nullptr, // No file upload handler
        [this](AsyncWebServerRequest* request, uint8_t* data, size_t len, size_t index, size_t total) {
            // This is called for body data
            if (index == 0) {
                // First chunk - could allocate buffers if needed
            }

            if (index + len == total) {
                // Last chunk - process the complete request
                handleCommandRequest(request, data, len);
            }
        }
    );

    // GET /api/status - Get system status
    _server.on("/api/status", HTTP_GET,
        [this](AsyncWebServerRequest* request) {
            handleStatusRequest(request);
        }
    );

    // GET /api/ping - Health check
    _server.on("/api/ping", HTTP_GET,
        [this](AsyncWebServerRequest* request) {
            handlePingRequest(request);
        }
    );

    // Enable CORS for API endpoints (allows web apps to call the API)
    DefaultHeaders::Instance().addHeader("Access-Control-Allow-Origin", "*");
    DefaultHeaders::Instance().addHeader("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
    DefaultHeaders::Instance().addHeader("Access-Control-Allow-Headers", "Content-Type");

    LOG_INFO("HTTPRequestHandler - REST API endpoints registered");
    LOG_INFO("  POST /api/command - Execute commands");
    LOG_INFO("  GET  /api/status  - System status");
    LOG_INFO("  GET  /api/ping    - Health check");
}

void HTTPRequestHandler::setCommandHandlerReference(CommandHandler* handler) {
    _commandHandler = handler;
    LOG_DEBUG("HTTPRequestHandler - CommandHandler reference set");
}

bool HTTPRequestHandler::isHealthy() const {
    // HTTP handler is healthy if it has been initialized with dependencies
    return _commandHandler != nullptr;
}

void HTTPRequestHandler::handleCommandRequest(AsyncWebServerRequest* request, uint8_t* data, size_t len) {
    if (!_commandHandler) {
        sendErrorResponse(request, 503, "Command handler not initialized");
        return;
    }

    // Parse JSON from body
    JsonDocument doc;
    DeserializationError error = deserializeJson(doc, data, len);

    if (error) {
        LOG_WARNING("HTTPRequestHandler - JSON parse error: %s", error.c_str());
        sendErrorResponse(request, 400, "Invalid JSON");
        return;
    }

    LOG_DEBUG("HTTPRequestHandler - Processing command via HTTP");

    // Create message context for HTTP (treat as WebSocket with special ID)
    CommandHandler::MessageContext context(CommandHandler::MessageSource::WEBSOCKET, 0xFFFFFFFF);

    // Capture request pointer for response
    AsyncWebServerRequest* capturedRequest = request;
    bool responseSent = false;

    // Set temporary response callback to capture the response
    auto originalCallback = [capturedRequest, &responseSent](const String& response, const CommandHandler::MessageContext& ctx) {
        if (!responseSent && capturedRequest != nullptr) {
            capturedRequest->send(200, "application/json", response);
            responseSent = true;
        }
    };

    // Temporarily override the command handler's response callback
    // Note: This requires the CommandHandler to support callback override
    // For now, we'll process and let the normal flow handle it

    // Process the command
    _commandHandler->processCommand(doc, context);

    // If no response was sent by the callback, send a generic success
    if (!responseSent) {
        sendJsonResponse(request, 200, "{\"status\":\"ok\",\"message\":\"Command processed\"}");
    }
}

void HTTPRequestHandler::handleStatusRequest(AsyncWebServerRequest* request) {
    if (!_commandHandler) {
        sendErrorResponse(request, 503, "Command handler not initialized");
        return;
    }

    LOG_DEBUG("HTTPRequestHandler - Status request via HTTP");

    // Create a status command
    JsonDocument doc;
    doc["group"] = "system";
    doc["action"] = "status";

    // Create message context
    CommandHandler::MessageContext context(CommandHandler::MessageSource::WEBSOCKET, 0xFFFFFFFF);

    // Capture request for response
    AsyncWebServerRequest* capturedRequest = request;
    bool responseSent = false;

    // Process via command handler
    _commandHandler->processCommand(doc, context);

    // Fallback response if needed
    if (!responseSent) {
        JsonDocument response;
        response["status"] = "ok";
        response["device_uid"] = _configManager.getDeviceUID();
        response["fw_version"] = _configManager.getFwVersion();

        String output;
        serializeJson(response, output);
        sendJsonResponse(request, 200, output);
    }
}

void HTTPRequestHandler::handlePingRequest(AsyncWebServerRequest* request) {
    LOG_DEBUG("HTTPRequestHandler - Ping request via HTTP");

    JsonDocument response;
    response["status"] = "ok";
    response["message"] = "pong";
    response["uptime"] = millis();

    String output;
    serializeJson(response, output);
    sendJsonResponse(request, 200, output);
}

void HTTPRequestHandler::sendJsonResponse(AsyncWebServerRequest* request, int code, const String& json) {
    request->send(code, "application/json", json);
}

void HTTPRequestHandler::sendErrorResponse(AsyncWebServerRequest* request, int code, const String& error) {
    JsonDocument doc;
    doc["status"] = "error";
    doc["error"] = error;

    String output;
    serializeJson(doc, output);
    sendJsonResponse(request, code, output);
}