/*
 * Copyright 2025 Google. This software is provided as-is, without warranty or representation for any use or purpose.
 * Your use of it is subject to your agreement with Google.
 */

package com.example.mapper.rag;

import com.example.dto.dialogflow.base.DetectIntentRequestDTO;
import com.example.dto.dialogflow.conversation.QueryInputDTO;
import com.example.dto.rag.RagQueryRequest;
import com.example.dto.rag.RagQueryRequest.NotificationContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

/**
 * Mapper component responsible for converting DetectIntentRequestDTO to RAG API format.
 * This adapter preserves the existing DTO structure while translating to the simpler RAG API.
 */
@Component
public class RagRequestMapper {

    private static final Logger logger = LoggerFactory.getLogger(RagRequestMapper.class);
    private static final String NOTIFICATION_PREFIX = "notification_po_";
    private static final String NOTIFICATION_TEXT_PARAM = "notification_text";

    /**
     * Maps a DetectIntentRequestDTO to a RagQueryRequest.
     * Extracts the phone number, text/event, and notification data from the existing structure.
     *
     * @param requestDto The existing DetectIntentRequestDTO
     * @param sessionId The session ID (not used by RAG but kept for logging)
     * @return A RagQueryRequest ready to send to the RAG server
     */
    public RagQueryRequest mapToRagRequest(DetectIntentRequestDTO requestDto, String sessionId) {
        Objects.requireNonNull(requestDto, "DetectIntentRequestDTO cannot be null");

        logger.debug("Mapping DetectIntentRequestDTO to RagQueryRequest for session: {}", sessionId);

        // Extract phone number from parameters
        Map<String, Object> parameters = requestDto.queryParams() != null
            ? requestDto.queryParams().parameters()
            : Map.of();

        String phoneNumber = extractPhoneNumber(parameters);
        if (phoneNumber == null || phoneNumber.isBlank()) {
            logger.error("Phone number is required but not found in request parameters");
            throw new IllegalArgumentException("Phone number is required in request parameters");
        }

        // Extract text or event from QueryInputDTO
        QueryInputDTO queryInput = requestDto.queryInput();
        String text = extractText(queryInput);
        String languageCode = queryInput.languageCode();

        // Determine request type and notification context
        String type = determineRequestType(queryInput, parameters);
        NotificationContext notificationContext = extractNotificationContext(parameters);

        RagQueryRequest ragRequest = new RagQueryRequest(
            phoneNumber,
            text,
            type,
            notificationContext,
            languageCode
        );

        logger.debug("Mapped RAG request: type={}, phoneNumber={}, hasNotification={}",
            type, phoneNumber, notificationContext != null);

        return ragRequest;
    }

    /**
     * Extracts the phone number from request parameters.
     */
    private String extractPhoneNumber(Map<String, Object> parameters) {
        Object telefono = parameters.get("telefono");
        if (telefono instanceof String) {
            return (String) telefono;
        }
        logger.warn("Phone number (telefono) not found or not a string in parameters");
        return null;
    }

    /**
     * Extracts text from QueryInputDTO (either text input or event).
     * For events, we use the event name as the text.
     */
    private String extractText(QueryInputDTO queryInput) {
        if (queryInput.text() != null && queryInput.text().text() != null
                && !queryInput.text().text().trim().isEmpty()) {
            return queryInput.text().text();
        } else if (queryInput.event() != null && queryInput.event().event() != null
                && !queryInput.event().event().trim().isEmpty()) {
            // For events (like "LLM_RESPONSE_PROCESSED"), use the event name
            return queryInput.event().event();
        } else {
            logger.error("Query input must contain either text or event");
            throw new IllegalArgumentException("Query input must contain either text or event");
        }
    }

    /**
     * Determines if this is a conversation or notification request.
     * If notification parameters are present, it's a notification request.
     */
    private String determineRequestType(QueryInputDTO queryInput, Map<String, Object> parameters) {
        // Check if there are notification-prefixed parameters
        boolean hasNotificationParams = parameters.keySet().stream()
            .anyMatch(key -> key.startsWith(NOTIFICATION_PREFIX));

        // Check if there's a notification_text parameter
        boolean hasNotificationText = parameters.containsKey(NOTIFICATION_TEXT_PARAM);

        // Check if the input is an event (notifications use events)
        boolean isEvent = queryInput.event() != null && queryInput.event().event() != null;

        if (hasNotificationParams || hasNotificationText ||
            (isEvent && "notificacion".equals(queryInput.event().event()))) {
            return "notification";
        }

        return "conversation";
    }

    /**
     * Extracts notification context from parameters.
     * Looks for notification_text and notification_po_* parameters.
     */
    private NotificationContext extractNotificationContext(Map<String, Object> parameters) {
        String notificationText = (String) parameters.get(NOTIFICATION_TEXT_PARAM);

        // Extract all notification_po_* parameters and remove the prefix
        Map<String, Object> notificationParams = new HashMap<>();
        parameters.forEach((key, value) -> {
            if (key.startsWith(NOTIFICATION_PREFIX)) {
                String cleanKey = key.substring(NOTIFICATION_PREFIX.length());
                notificationParams.put(cleanKey, value);
            }
        });

        // Only create NotificationContext if we have notification data
        if (notificationText != null || !notificationParams.isEmpty()) {
            return new NotificationContext(notificationText, notificationParams);
        }

        return null;
    }
}