import { describe, it, expect, beforeEach, vi } from "vitest";
import { Test, TestingModule } from "@nestjs/testing";
import { KnowledgeService } from "./knowledge.service";
import { PrismaService } from "../prisma/prisma.service";
import { LinkSyncService } from "./services/link-sync.service";
import { KnowledgeCacheService } from "./services/cache.service";
import { EmbeddingService } from "./services/embedding.service";
import { OllamaEmbeddingService } from "./services/ollama-embedding.service";
import { EmbeddingQueueService } from "./queues/embedding-queue.service";

describe("KnowledgeService - Embedding Error Logging", () => {
  let service: KnowledgeService;
  let mockEmbeddingQueueService: {
    queueEmbeddingJob: ReturnType<typeof vi.fn>;
  };

  const workspaceId = "workspace-123";
  const userId = "user-456";
  const entryId = "entry-789";
  const slug = "test-entry";

  const mockCreatedEntry = {
    id: entryId,
    workspaceId,
    slug,
    title: "Test Entry",
    content: "# Test Content",
    contentHtml: "<h1>Test Content</h1>",
    summary: "Test summary",
    status: "DRAFT",
    visibility: "PRIVATE",
    createdAt: new Date("2026-01-01"),
    updatedAt: new Date("2026-01-01"),
    createdBy: userId,
    updatedBy: userId,
    tags: [],
  };

  const mockPrismaService = {
    knowledgeEntry: {
      findUnique: vi.fn(),
      create: vi.fn(),
      update: vi.fn(),
      count: vi.fn(),
      findMany: vi.fn(),
    },
    knowledgeEntryVersion: {
      create: vi.fn(),
      count: vi.fn(),
      findMany: vi.fn(),
    },
    knowledgeEntryTag: {
      deleteMany: vi.fn(),
    },
    knowledgeTag: {
      findUnique: vi.fn(),
      create: vi.fn(),
    },
    $transaction: vi.fn(),
  };

  const mockLinkSyncService = {
    syncLinks: vi.fn().mockResolvedValue(undefined),
  };

  const mockCacheService = {
    getEntry: vi.fn().mockResolvedValue(null),
    setEntry: vi.fn().mockResolvedValue(undefined),
    invalidateEntry: vi.fn().mockResolvedValue(undefined),
    invalidateSearches: vi.fn().mockResolvedValue(undefined),
    invalidateGraphs: vi.fn().mockResolvedValue(undefined),
    invalidateGraphsForEntry: vi.fn().mockResolvedValue(undefined),
  };

  const mockEmbeddingService = {
    isConfigured: vi.fn().mockReturnValue(false),
    prepareContentForEmbedding: vi.fn().mockReturnValue("prepared content"),
    batchGenerateEmbeddings: vi.fn().mockResolvedValue(0),
  };

  const mockOllamaEmbeddingService = {
    isConfigured: vi.fn().mockResolvedValue(false),
    prepareContentForEmbedding: vi.fn().mockReturnValue("prepared content"),
    generateAndStoreEmbedding: vi.fn().mockResolvedValue(undefined),
  };

  beforeEach(async () => {
    mockEmbeddingQueueService = {
      queueEmbeddingJob: vi.fn(),
    };

    const module: TestingModule = await Test.createTestingModule({
      providers: [
        KnowledgeService,
        {
          provide: PrismaService,
          useValue: mockPrismaService,
        },
        {
          provide: LinkSyncService,
          useValue: mockLinkSyncService,
        },
        {
          provide: KnowledgeCacheService,
          useValue: mockCacheService,
        },
        {
          provide: EmbeddingService,
          useValue: mockEmbeddingService,
        },
        {
          provide: OllamaEmbeddingService,
          useValue: mockOllamaEmbeddingService,
        },
        {
          provide: EmbeddingQueueService,
          useValue: mockEmbeddingQueueService,
        },
      ],
    }).compile();

    service = module.get<KnowledgeService>(KnowledgeService);

    vi.clearAllMocks();
  });

  describe("create - embedding failure logging", () => {
    it("should log structured warning when embedding generation fails during create", async () => {
      // Setup: transaction returns created entry
      mockPrismaService.$transaction.mockResolvedValue(mockCreatedEntry);
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(null); // For slug uniqueness check

      // Make embedding queue fail
      const embeddingError = new Error("Ollama service unavailable");
      mockEmbeddingQueueService.queueEmbeddingJob.mockRejectedValue(embeddingError);

      // Spy on the logger
      const loggerWarnSpy = vi.spyOn(service["logger"], "warn");

      // Create entry
      await service.create(workspaceId, userId, {
        title: "Test Entry",
        content: "# Test Content",
      });

      // Wait for async embedding generation to complete (and fail)
      await new Promise((resolve) => setTimeout(resolve, 10));

      // Verify structured logging was called
      expect(loggerWarnSpy).toHaveBeenCalledWith(
        expect.stringContaining("Failed to generate embedding for entry"),
        expect.objectContaining({
          entryId,
          workspaceId,
          error: "Ollama service unavailable",
        })
      );
    });

    it("should include entry ID and workspace ID in error context during create", async () => {
      mockPrismaService.$transaction.mockResolvedValue(mockCreatedEntry);
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(null);

      mockEmbeddingQueueService.queueEmbeddingJob.mockRejectedValue(
        new Error("Connection timeout")
      );

      const loggerWarnSpy = vi.spyOn(service["logger"], "warn");

      await service.create(workspaceId, userId, {
        title: "Test Entry",
        content: "# Test Content",
      });

      await new Promise((resolve) => setTimeout(resolve, 10));

      // Verify the structured context contains required fields
      const callArgs = loggerWarnSpy.mock.calls[0];
      expect(callArgs[1]).toHaveProperty("entryId", entryId);
      expect(callArgs[1]).toHaveProperty("workspaceId", workspaceId);
      expect(callArgs[1]).toHaveProperty("error", "Connection timeout");
    });

    it("should handle non-Error objects in embedding failure during create", async () => {
      mockPrismaService.$transaction.mockResolvedValue(mockCreatedEntry);
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(null);

      // Reject with a string instead of Error
      mockEmbeddingQueueService.queueEmbeddingJob.mockRejectedValue("String error message");

      const loggerWarnSpy = vi.spyOn(service["logger"], "warn");

      await service.create(workspaceId, userId, {
        title: "Test Entry",
        content: "# Test Content",
      });

      await new Promise((resolve) => setTimeout(resolve, 10));

      // Should convert non-Error to string
      expect(loggerWarnSpy).toHaveBeenCalledWith(
        expect.any(String),
        expect.objectContaining({
          error: "String error message",
        })
      );
    });
  });

  describe("update - embedding failure logging", () => {
    const existingEntry = {
      ...mockCreatedEntry,
      versions: [{ version: 1 }],
    };

    const updatedEntry = {
      ...mockCreatedEntry,
      title: "Updated Title",
      content: "# Updated Content",
    };

    it("should log structured warning when embedding generation fails during update", async () => {
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(existingEntry);
      mockPrismaService.$transaction.mockResolvedValue(updatedEntry);

      const embeddingError = new Error("Embedding model not loaded");
      mockEmbeddingQueueService.queueEmbeddingJob.mockRejectedValue(embeddingError);

      const loggerWarnSpy = vi.spyOn(service["logger"], "warn");

      await service.update(workspaceId, slug, userId, {
        content: "# Updated Content",
      });

      await new Promise((resolve) => setTimeout(resolve, 10));

      expect(loggerWarnSpy).toHaveBeenCalledWith(
        expect.stringContaining("Failed to generate embedding for entry"),
        expect.objectContaining({
          entryId,
          workspaceId,
          error: "Embedding model not loaded",
        })
      );
    });

    it("should include entry ID and workspace ID in error context during update", async () => {
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(existingEntry);
      mockPrismaService.$transaction.mockResolvedValue(updatedEntry);

      mockEmbeddingQueueService.queueEmbeddingJob.mockRejectedValue(
        new Error("Rate limit exceeded")
      );

      const loggerWarnSpy = vi.spyOn(service["logger"], "warn");

      await service.update(workspaceId, slug, userId, {
        title: "New Title",
      });

      await new Promise((resolve) => setTimeout(resolve, 10));

      const callArgs = loggerWarnSpy.mock.calls[0];
      expect(callArgs[1]).toHaveProperty("entryId", entryId);
      expect(callArgs[1]).toHaveProperty("workspaceId", workspaceId);
      expect(callArgs[1]).toHaveProperty("error", "Rate limit exceeded");
    });

    it("should not trigger embedding generation if only status is updated", async () => {
      mockPrismaService.knowledgeEntry.findUnique.mockResolvedValue(existingEntry);
      mockPrismaService.$transaction.mockResolvedValue({
        ...existingEntry,
        status: "PUBLISHED",
      });

      await service.update(workspaceId, slug, userId, {
        status: "PUBLISHED",
      });

      await new Promise((resolve) => setTimeout(resolve, 10));

      // Embedding should not be called when only status changes
      expect(mockEmbeddingQueueService.queueEmbeddingJob).not.toHaveBeenCalled();
    });
  });
});