package com.dalab.policyengine.controller;

import static org.mockito.ArgumentMatchers.*;
import static org.mockito.Mockito.*;
import static org.springframework.security.test.web.servlet.request.SecurityMockMvcRequestPostProcessors.*;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.*;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;

import java.time.LocalDateTime;
import java.util.*;

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.http.MediaType;
import org.springframework.security.test.context.support.WithMockUser;
import org.springframework.test.context.ActiveProfiles;
import org.springframework.test.web.servlet.MockMvc;

import com.dalab.policyengine.dto.*;
import com.dalab.policyengine.model.Policy;
import com.dalab.policyengine.model.PolicyDraft;
import com.dalab.policyengine.model.PolicyStatus;
import com.dalab.policyengine.service.IPolicyService;
import com.dalab.policyengine.service.IPolicyEvaluationService;
import com.dalab.policyengine.service.IPolicyDraftService;
import com.dalab.policyengine.service.IEventSubscriptionService;
import com.fasterxml.jackson.databind.ObjectMapper;

@WebMvcTest(PolicyController.class)
@ExtendWith(MockitoExtension.class)
@ActiveProfiles("test")
class PolicyControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @MockBean
    private IPolicyService policyService;

    @MockBean
    private IPolicyEvaluationService policyEvaluationService;

    @MockBean
    private IPolicyDraftService policyDraftService;

    @MockBean
    private IEventSubscriptionService eventSubscriptionService;

    @Autowired
    private ObjectMapper objectMapper;

    private Policy testPolicy;
    private PolicyDTO testPolicyDTO;
    private PolicyDraft testPolicyDraft;
    private PolicyDraftDTO testPolicyDraftDTO;
    private PolicyEvaluationRequestDTO testEvaluationRequest;
    private PolicyImpactRequestDTO testImpactRequest;
    private PolicyImpactResponseDTO testImpactResponse;

    @BeforeEach
    void setUp() {
        // Create test policy
        testPolicy = new Policy();
        testPolicy.setId(UUID.randomUUID());
        testPolicy.setName("Test Policy");
        testPolicy.setDescription("Test policy for compliance");
        testPolicy.setRulesContent("when asset.type == 'PII' then tag('SENSITIVE')");
        testPolicy.setStatus(PolicyStatus.ENABLED);
        testPolicy.setCreatedAt(LocalDateTime.now());
        testPolicy.setUpdatedAt(LocalDateTime.now());

        // Create test policy DTO
        testPolicyDTO = PolicyDTO.builder()
            .id(testPolicy.getId())
            .name("Test Policy")
            .description("Test policy for compliance")
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE')")
            .status("ENABLED")
            .createdAt(LocalDateTime.now())
            .updatedAt(LocalDateTime.now())
            .build();

        // Create test policy draft
        testPolicyDraft = new PolicyDraft();
        testPolicyDraft.setId(UUID.randomUUID());
        testPolicyDraft.setName("Test Draft Policy");
        testPolicyDraft.setDescription("Draft policy for testing");
        testPolicyDraft.setRulesContent("when asset.type == 'PHI' then tag('HEALTHCARE')");
        testPolicyDraft.setStatus("DRAFT");
        testPolicyDraft.setCreatedAt(LocalDateTime.now());

        // Create test policy draft DTO
        testPolicyDraftDTO = PolicyDraftDTO.builder()
            .id(testPolicyDraft.getId())
            .name("Test Draft Policy")
            .description("Draft policy for testing")
            .rulesContent("when asset.type == 'PHI' then tag('HEALTHCARE')")
            .status("DRAFT")
            .createdAt(LocalDateTime.now())
            .build();

        // Create test evaluation request
        testEvaluationRequest = PolicyEvaluationRequestDTO.builder()
            .policyId(testPolicy.getId())
            .assetId(UUID.randomUUID())
            .evaluationContext(Map.of("asset.type", "PII"))
            .build();

        // Create test impact request
        testImpactRequest = PolicyImpactRequestDTO.builder()
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE')")
            .analysisType("FULL")
            .includePerformanceEstimate(true)
            .includeCostImpact(true)
            .includeComplianceImpact(true)
            .build();

        // Create test impact response
        testImpactResponse = PolicyImpactResponseDTO.builder()
            .analysisId("impact-12345678")
            .analysisType("FULL")
            .build();
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void createPolicy_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyCreateRequestDTO request = PolicyCreateRequestDTO.builder()
            .name("New Test Policy")
            .description("New test policy for compliance")
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE')")
            .build();

        when(policyService.createPolicy(any(PolicyCreateRequestDTO.class))).thenReturn(testPolicyDTO);

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isCreated())
            .andExpect(jsonPath("$.id").value(testPolicy.getId().toString()))
            .andExpect(jsonPath("$.name").value("Test Policy"))
            .andExpect(jsonPath("$.status").value("ENABLED"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_USER")
    void createPolicy_AsUser_ShouldBeForbidden() throws Exception {
        // Given
        PolicyCreateRequestDTO request = PolicyCreateRequestDTO.builder()
            .name("New Test Policy")
            .description("New test policy for compliance")
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE')")
            .build();

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isForbidden());
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void getAllPolicies_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        List<PolicyDTO> policyList = Arrays.asList(testPolicyDTO);
        Page<PolicyDTO> policyPage = new PageImpl<>(policyList, PageRequest.of(0, 20), 1);

        when(policyService.getAllPolicies(any(Pageable.class))).thenReturn(policyPage);

        // When & Then
        mockMvc.perform(get("/api/v1/policyengine/policies")
                .param("page", "0")
                .param("size", "20"))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.content[0].id").value(testPolicy.getId().toString()))
            .andExpect(jsonPath("$.content[0].name").value("Test Policy"))
            .andExpect(jsonPath("$.totalElements").value(1));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void getPolicyById_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        when(policyService.getPolicyById(testPolicy.getId())).thenReturn(Optional.of(testPolicyDTO));

        // When & Then
        mockMvc.perform(get("/api/v1/policyengine/policies/{policyId}", testPolicy.getId()))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.id").value(testPolicy.getId().toString()))
            .andExpect(jsonPath("$.name").value("Test Policy"))
            .andExpect(jsonPath("$.status").value("ENABLED"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void getPolicyById_PolicyNotFound_ShouldReturnNotFound() throws Exception {
        // Given
        UUID nonExistentId = UUID.randomUUID();
        when(policyService.getPolicyById(nonExistentId)).thenReturn(Optional.empty());

        // When & Then
        mockMvc.perform(get("/api/v1/policyengine/policies/{policyId}", nonExistentId))
            .andExpect(status().isNotFound());
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void updatePolicy_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyUpdateRequestDTO request = PolicyUpdateRequestDTO.builder()
            .name("Updated Test Policy")
            .description("Updated test policy for compliance")
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE') and notify('admin')")
            .status("ENABLED")
            .build();

        PolicyDTO updatedPolicy = PolicyDTO.builder()
            .id(testPolicy.getId())
            .name("Updated Test Policy")
            .description("Updated test policy for compliance")
            .rulesContent("when asset.type == 'PII' then tag('SENSITIVE') and notify('admin')")
            .status("ENABLED")
            .createdAt(LocalDateTime.now())
            .updatedAt(LocalDateTime.now())
            .build();

        when(policyService.updatePolicy(eq(testPolicy.getId()), any(PolicyUpdateRequestDTO.class)))
            .thenReturn(updatedPolicy);

        // When & Then
        mockMvc.perform(put("/api/v1/policyengine/policies/{policyId}", testPolicy.getId())
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.id").value(testPolicy.getId().toString()))
            .andExpect(jsonPath("$.name").value("Updated Test Policy"))
            .andExpect(jsonPath("$.status").value("ENABLED"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void deletePolicy_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        doNothing().when(policyService).deletePolicy(testPolicy.getId());

        // When & Then
        mockMvc.perform(delete("/api/v1/policyengine/policies/{policyId}", testPolicy.getId())
                .with(csrf()))
            .andExpect(status().isNoContent());
    }

    @Test
    @WithMockUser(authorities = "ROLE_USER")
    void deletePolicy_AsUser_ShouldBeForbidden() throws Exception {
        // When & Then
        mockMvc.perform(delete("/api/v1/policyengine/policies/{policyId}", testPolicy.getId())
                .with(csrf()))
            .andExpect(status().isForbidden());
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void evaluatePolicy_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyEvaluationResponseDTO evaluationResponse = PolicyEvaluationResponseDTO.builder()
            .policyId(testPolicy.getId())
            .assetId(testEvaluationRequest.getAssetId())
            .evaluationResult("PASS")
            .actions(Arrays.asList("tag('SENSITIVE')"))
            .evaluationTimestamp(LocalDateTime.now())
            .build();

        when(policyEvaluationService.evaluatePolicy(any(PolicyEvaluationRequestDTO.class)))
            .thenReturn(evaluationResponse);

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/evaluate")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(testEvaluationRequest)))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.policyId").value(testPolicy.getId().toString()))
            .andExpect(jsonPath("$.evaluationResult").value("PASS"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void analyzePolicyImpact_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        when(policyService.analyzePolicy(any(PolicyImpactRequestDTO.class)))
            .thenReturn(testImpactResponse);

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/{policyId}/impact-preview", testPolicy.getId())
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(testImpactRequest)))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.analysisId").value("impact-12345678"))
            .andExpect(jsonPath("$.analysisType").value("FULL"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void createPolicyDraft_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyDraftCreateRequestDTO request = PolicyDraftCreateRequestDTO.builder()
            .name("New Draft Policy")
            .description("New draft policy for testing")
            .rulesContent("when asset.type == 'PHI' then tag('HEALTHCARE')")
            .build();

        when(policyDraftService.createPolicyDraft(any(PolicyDraftCreateRequestDTO.class)))
            .thenReturn(testPolicyDraftDTO);

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/drafts")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isCreated())
            .andExpect(jsonPath("$.id").value(testPolicyDraft.getId().toString()))
            .andExpect(jsonPath("$.name").value("Test Draft Policy"))
            .andExpect(jsonPath("$.status").value("DRAFT"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void getAllPolicyDrafts_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        List<PolicyDraftDTO> draftList = Arrays.asList(testPolicyDraftDTO);
        Page<PolicyDraftDTO> draftPage = new PageImpl<>(draftList, PageRequest.of(0, 20), 1);

        when(policyDraftService.getAllPolicyDrafts(any(Pageable.class))).thenReturn(draftPage);

        // When & Then
        mockMvc.perform(get("/api/v1/policyengine/policies/drafts")
                .param("page", "0")
                .param("size", "20"))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.content[0].id").value(testPolicyDraft.getId().toString()))
            .andExpect(jsonPath("$.content[0].name").value("Test Draft Policy"))
            .andExpect(jsonPath("$.totalElements").value(1));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void getPolicyDraftById_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        when(policyDraftService.getPolicyDraftById(testPolicyDraft.getId()))
            .thenReturn(Optional.of(testPolicyDraftDTO));

        // When & Then
        mockMvc.perform(get("/api/v1/policyengine/policies/drafts/{draftId}", testPolicyDraft.getId()))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.id").value(testPolicyDraft.getId().toString()))
            .andExpect(jsonPath("$.name").value("Test Draft Policy"))
            .andExpect(jsonPath("$.status").value("DRAFT"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void updatePolicyDraft_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyDraftUpdateRequestDTO request = PolicyDraftUpdateRequestDTO.builder()
            .name("Updated Draft Policy")
            .description("Updated draft policy for testing")
            .rulesContent("when asset.type == 'PHI' then tag('HEALTHCARE') and encrypt()")
            .build();

        PolicyDraftDTO updatedDraft = PolicyDraftDTO.builder()
            .id(testPolicyDraft.getId())
            .name("Updated Draft Policy")
            .description("Updated draft policy for testing")
            .rulesContent("when asset.type == 'PHI' then tag('HEALTHCARE') and encrypt()")
            .status("DRAFT")
            .createdAt(LocalDateTime.now())
            .updatedAt(LocalDateTime.now())
            .build();

        when(policyDraftService.updatePolicyDraft(eq(testPolicyDraft.getId()), any(PolicyDraftUpdateRequestDTO.class)))
            .thenReturn(updatedDraft);

        // When & Then
        mockMvc.perform(put("/api/v1/policyengine/policies/drafts/{draftId}", testPolicyDraft.getId())
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.id").value(testPolicyDraft.getId().toString()))
            .andExpect(jsonPath("$.name").value("Updated Draft Policy"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void approvePolicyDraft_AsDataEngineer_ShouldSucceed() throws Exception {
        // Given
        PolicyDraftApprovalRequestDTO request = PolicyDraftApprovalRequestDTO.builder()
            .approved(true)
            .comments("Approved for production use")
            .build();

        PolicyDTO approvedPolicy = PolicyDTO.builder()
            .id(UUID.randomUUID())
            .name("Approved Policy")
            .description("Policy approved from draft")
            .rulesContent("when asset.type == 'PHI' then tag('HEALTHCARE')")
            .status("ENABLED")
            .createdAt(LocalDateTime.now())
            .updatedAt(LocalDateTime.now())
            .build();

        when(policyDraftService.approvePolicyDraft(eq(testPolicyDraft.getId()), any(PolicyDraftApprovalRequestDTO.class)))
            .thenReturn(approvedPolicy);

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/drafts/{draftId}/approve", testPolicyDraft.getId())
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.name").value("Approved Policy"))
            .andExpect(jsonPath("$.status").value("ENABLED"));
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void createPolicy_InvalidRequest_ShouldReturnBadRequest() throws Exception {
        // Given
        PolicyCreateRequestDTO request = PolicyCreateRequestDTO.builder()
            .name("") // Invalid: empty name
            .description("Test policy")
            .rulesContent("invalid rule syntax")
            .build();

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isBadRequest());
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void evaluatePolicy_InvalidRequest_ShouldReturnBadRequest() throws Exception {
        // Given
        PolicyEvaluationRequestDTO request = PolicyEvaluationRequestDTO.builder()
            .policyId(null) // Invalid: null policy ID
            .assetId(UUID.randomUUID())
            .evaluationContext(Map.of("asset.type", "PII"))
            .build();

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/evaluate")
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isBadRequest());
    }

    @Test
    @WithMockUser(authorities = "ROLE_DATA_ENGINEER")
    void analyzePolicyImpact_InvalidRequest_ShouldReturnBadRequest() throws Exception {
        // Given
        PolicyImpactRequestDTO request = PolicyImpactRequestDTO.builder()
            .rulesContent("") // Invalid: empty rules content
            .analysisType("INVALID_TYPE") // Invalid: unknown analysis type
            .build();

        // When & Then
        mockMvc.perform(post("/api/v1/policyengine/policies/{policyId}/impact-preview", testPolicy.getId())
                .with(csrf())
                .contentType(MediaType.APPLICATION_JSON)
                .content(objectMapper.writeValueAsString(request)))
            .andExpect(status().isBadRequest());
    }
}