package com.example.service.unit_testing;

import com.example.dto.dialogflow.base.DetectIntentResponseDTO;
import com.example.dto.dialogflow.conversation.*;
import com.example.dto.quickreplies.QuestionDTO;
import com.example.dto.quickreplies.QuickReplyDTO;
import com.example.mapper.conversation.ConversationEntryMapper;
import com.example.service.conversation.ConversationManagerService;
import com.example.service.conversation.FirestoreConversationService;
import com.example.service.conversation.MemoryStoreConversationService;
import com.example.service.quickreplies.QuickRepliesManagerService;
import com.example.service.quickreplies.QuickReplyContentService;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;
import reactor.test.StepVerifier;

import java.time.Instant;
import java.util.List;

import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyString;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.Mockito.*;

@ExtendWith(MockitoExtension.class)
class QuickRepliesManagerServiceTest {

    @Mock private MemoryStoreConversationService memoryStoreConversationService;
    @Mock private FirestoreConversationService firestoreConversationService;
    @Mock private QuickReplyContentService quickReplyContentService;
    @Mock private ConversationManagerService conversationManagerService;
    @Mock private ConversationEntryMapper conversationEntryMapper;

    private QuickRepliesManagerService quickRepliesManagerService;

    // Test Data
    private final String PHONE = "5555555555";
    private final String SESSION_ID = "session-123";
    private final String USER_ID = "user_by_phone_5555555555";
    private final String CONTEXTO = "pagos";
    
    @BeforeEach
    void setUp() {
        quickRepliesManagerService = new QuickRepliesManagerService(
                conversationManagerService,
                memoryStoreConversationService,
                firestoreConversationService,
                quickReplyContentService,
                conversationEntryMapper
        );
    }

    @Test
    @DisplayName("manageConversation - Count 0 - NO MATCH: Should clear context and delegate to Dialogflow")
    void manageConversation_Count0_NoMatch_ShouldDelegate() {
        // 1. SETUP: User typed "Hola", but context "pagos" is active.
        ExternalConvRequestDTO request = new ExternalConvRequestDTO("Hola", new UsuarioDTO(PHONE, "Nick"), "whatsapp", ConversationEntryType.CONVERSACION, null);
        ConversationSessionDTO session = new ConversationSessionDTO(SESSION_ID, USER_ID, PHONE, Instant.now(), Instant.now(), "last", CONTEXTO);

        // Mock Session Retrieval
        when(memoryStoreConversationService.getSessionByTelefono(PHONE)).thenReturn(Mono.just(session));

        // Mock History: Only the SYSTEM message (The Menu) exists. Count = 0.
        ConversationMessageDTO sysMsg = new ConversationMessageDTO(MessageType.SYSTEM, Instant.now(), "Menu...", null, "whatsapp");
        when(memoryStoreConversationService.getMessages(SESSION_ID)).thenReturn(Flux.just(sysMsg));

        // Mock QR Content: The menu has options, but "Hola" is NOT one of them.
        QuestionDTO q1 = new QuestionDTO("Ver Saldo", "desc", "Tu saldo is 10");
        QuickReplyDTO qrDto = new QuickReplyDTO("Header", "Body", "Btn", "Section", List.of(q1));
        when(quickReplyContentService.getQuickReplies(CONTEXTO)).thenReturn(Mono.just(qrDto));

        // Mock Orchestrator Delegation (The expected outcome)
        DetectIntentResponseDTO delegatedResponse = new DetectIntentResponseDTO("df-response", new QueryResultDTO("Hola soy Beto", null));
        when(memoryStoreConversationService.updateSession(any())).thenReturn(Mono.empty()); // Clearing context
        when(conversationManagerService.manageConversation(request)).thenReturn(Mono.just(delegatedResponse));

        // 2. EXECUTE
        StepVerifier.create(quickRepliesManagerService.manageConversation(request))
                .expectNext(delegatedResponse)
                .verifyComplete();

        // 3. VERIFY
        // Ensure we cleared the context
        verify(memoryStoreConversationService).updateSession(argThat(s -> s.pantallaContexto() == null));
        // Ensure we called the normal conversation manager
        verify(conversationManagerService).manageConversation(request);
    }

    @Test
    @DisplayName("manageConversation - Count 0 - MATCH: Should return QR Answer")
    void manageConversation_Count0_Match_ShouldAnswer() {
        // 1. SETUP: User typed "Ver Saldo" (Valid Option)
        ExternalConvRequestDTO request = new ExternalConvRequestDTO("Ver Saldo", new UsuarioDTO(PHONE, "Nick"), "whatsapp", ConversationEntryType.CONVERSACION, null);
        ConversationSessionDTO session = new ConversationSessionDTO(SESSION_ID, USER_ID, PHONE, Instant.now(), Instant.now(), "last", CONTEXTO);

        when(memoryStoreConversationService.getSessionByTelefono(PHONE)).thenReturn(Mono.just(session));
        
        // Count 0 (Last message was System)
        ConversationMessageDTO sysMsg = new ConversationMessageDTO(MessageType.SYSTEM, Instant.now(), "Menu...", null, "whatsapp");
        when(memoryStoreConversationService.getMessages(SESSION_ID)).thenReturn(Flux.just(sysMsg));

        // Valid Option exists
        QuestionDTO q1 = new QuestionDTO("Ver Saldo", "desc", "Tu saldo es 100 pesos");
        QuickReplyDTO qrDto = new QuickReplyDTO("Header", "Body", "Btn", "Section", List.of(q1));
        when(quickReplyContentService.getQuickReplies(CONTEXTO)).thenReturn(Mono.just(qrDto));

        // Mocks for saving the conversation turn
        mockPersistence();
        when(memoryStoreConversationService.updateSession(any())).thenReturn(Mono.empty());

        // 2. EXECUTE
        StepVerifier.create(quickRepliesManagerService.manageConversation(request))
                .assertNext(response -> {
                    // Expect the pre-defined answer from the JSON
                    assert response.queryResult().responseText().equals("Tu saldo es 100 pesos");
                })
                .verifyComplete();
        
        // Verify we did NOT delegate
        verify(conversationManagerService, never()).manageConversation(any());
    }

    @Test
    @DisplayName("manageConversation - Count 1 - NO MATCH: Should save User Msg, Clear, and Delegate")
    void manageConversation_Count1_NoMatch_ShouldDelegate() {
        // 1. SETUP: User typed "Gracias" (Not an option)
        ExternalConvRequestDTO request = new ExternalConvRequestDTO("Gracias", new UsuarioDTO(PHONE, "Nick"), "whatsapp", ConversationEntryType.CONVERSACION, null);
        ConversationSessionDTO session = new ConversationSessionDTO(SESSION_ID, USER_ID, PHONE, Instant.now(), Instant.now(), "last", CONTEXTO);

        when(memoryStoreConversationService.getSessionByTelefono(PHONE)).thenReturn(Mono.just(session));

        // Mock History: System msg -> User msg (Invalid) -> Now this is the 2nd user msg (Count 1 logic)
        // Wait, logic says count is messages AFTER last init.
        // Sys (Init) -> User("Hola" - ignored previously) -> Current Request("Gracias")
        ConversationMessageDTO sysMsg = new ConversationMessageDTO(MessageType.SYSTEM, Instant.now(), "Menu...", null, "whatsapp");
        ConversationMessageDTO userMsg1 = new ConversationMessageDTO(MessageType.USER, Instant.now(), "Hola", null, "whatsapp");
        when(memoryStoreConversationService.getMessages(SESSION_ID)).thenReturn(Flux.just(sysMsg, userMsg1));

        QuestionDTO q1 = new QuestionDTO("Ver Saldo", "desc", "Tu saldo es 10");
        QuickReplyDTO qrDto = new QuickReplyDTO("Header", "Body", "Btn", "Section", List.of(q1));
        when(quickReplyContentService.getQuickReplies(CONTEXTO)).thenReturn(Mono.just(qrDto));

        // Mock persistence for the user message (Manual save in the else block)
        mockPersistence();
        
        // Mock Delegation
        DetectIntentResponseDTO delegatedResponse = new DetectIntentResponseDTO("df-response", new QueryResultDTO("De nada", null));
        when(memoryStoreConversationService.updateSession(any())).thenReturn(Mono.empty());
        when(conversationManagerService.manageConversation(request)).thenReturn(Mono.just(delegatedResponse));

        // 2. EXECUTE
        StepVerifier.create(quickRepliesManagerService.manageConversation(request))
                .expectNext(delegatedResponse)
                .verifyComplete();

        // 3. VERIFY
        // Ensure manual save was called (verifying flow of `persistConversationTurn`)
        verify(memoryStoreConversationService, times(1)).saveMessage(eq(SESSION_ID), any()); 
        verify(memoryStoreConversationService).updateSession(argThat(s -> s.pantallaContexto() == null));
        verify(conversationManagerService).manageConversation(request);
    }

    // Helper to mock the complex save chain
    private void mockPersistence() {
        when(conversationEntryMapper.toConversationMessageDTO(any())).thenReturn(new ConversationMessageDTO(MessageType.USER, Instant.now(), "text", null, "wa"));
        when(memoryStoreConversationService.saveSession(any())).thenReturn(Mono.empty());
        when(memoryStoreConversationService.saveMessage(anyString(), any())).thenReturn(Mono.empty());
        when(firestoreConversationService.saveSession(any())).thenReturn(Mono.empty());
        when(firestoreConversationService.saveMessage(anyString(), any())).thenReturn(Mono.empty());
    }
}