import { describe, it, expect } from "vitest";
import { BaseProvider } from "@/providers/base-provider.js";
import type {
  ProviderConfig,
  ExecuteOptions,
  ProviderMessage,
  InstallationStatus,
  ModelDefinition,
} from "@/providers/types.js";

// Concrete implementation for testing the abstract class
class TestProvider extends BaseProvider {
  getName(): string {
    return "test-provider";
  }

  async *executeQuery(
    _options: ExecuteOptions
  ): AsyncGenerator<ProviderMessage> {
    yield { type: "text", text: "test response" };
  }

  async detectInstallation(): Promise<InstallationStatus> {
    return { installed: true };
  }

  getAvailableModels(): ModelDefinition[] {
    return [
      { id: "test-model-1", name: "Test Model 1", description: "A test model" },
    ];
  }
}

describe("base-provider.ts", () => {
  describe("constructor", () => {
    it("should initialize with empty config when none provided", () => {
      const provider = new TestProvider();
      expect(provider.getConfig()).toEqual({});
    });

    it("should initialize with provided config", () => {
      const config: ProviderConfig = {
        apiKey: "test-key",
        baseUrl: "https://test.com",
      };
      const provider = new TestProvider(config);
      expect(provider.getConfig()).toEqual(config);
    });

    it("should call getName() during initialization", () => {
      const provider = new TestProvider();
      expect(provider.getName()).toBe("test-provider");
    });
  });

  describe("validateConfig", () => {
    it("should return valid when config exists", () => {
      const provider = new TestProvider({ apiKey: "test" });
      const result = provider.validateConfig();

      expect(result.valid).toBe(true);
      expect(result.errors).toHaveLength(0);
      expect(result.warnings).toHaveLength(0);
    });

    it("should return invalid when config is undefined", () => {
      // Create provider without config
      const provider = new TestProvider();
      // Manually set config to undefined to test edge case
      (provider as any).config = undefined;

      const result = provider.validateConfig();

      expect(result.valid).toBe(false);
      expect(result.errors).toContain("Provider config is missing");
    });

    it("should return valid for empty config object", () => {
      const provider = new TestProvider({});
      const result = provider.validateConfig();

      expect(result.valid).toBe(true);
      expect(result.errors).toHaveLength(0);
    });

    it("should include warnings array in result", () => {
      const provider = new TestProvider();
      const result = provider.validateConfig();

      expect(result).toHaveProperty("warnings");
      expect(Array.isArray(result.warnings)).toBe(true);
    });
  });

  describe("supportsFeature", () => {
    it("should support 'tools' feature", () => {
      const provider = new TestProvider();
      expect(provider.supportsFeature("tools")).toBe(true);
    });

    it("should support 'text' feature", () => {
      const provider = new TestProvider();
      expect(provider.supportsFeature("text")).toBe(true);
    });

    it("should not support unknown features", () => {
      const provider = new TestProvider();
      expect(provider.supportsFeature("vision")).toBe(false);
      expect(provider.supportsFeature("mcp")).toBe(false);
      expect(provider.supportsFeature("unknown")).toBe(false);
    });

    it("should be case-sensitive", () => {
      const provider = new TestProvider();
      expect(provider.supportsFeature("TOOLS")).toBe(false);
      expect(provider.supportsFeature("Text")).toBe(false);
    });
  });

  describe("getConfig", () => {
    it("should return current config", () => {
      const config: ProviderConfig = {
        apiKey: "test-key",
        model: "test-model",
      };
      const provider = new TestProvider(config);

      expect(provider.getConfig()).toEqual(config);
    });

    it("should return same reference", () => {
      const config: ProviderConfig = { apiKey: "test" };
      const provider = new TestProvider(config);

      const retrieved1 = provider.getConfig();
      const retrieved2 = provider.getConfig();

      expect(retrieved1).toBe(retrieved2);
    });
  });

  describe("setConfig", () => {
    it("should merge partial config with existing config", () => {
      const provider = new TestProvider({ apiKey: "original-key" });

      provider.setConfig({ model: "new-model" });

      expect(provider.getConfig()).toEqual({
        apiKey: "original-key",
        model: "new-model",
      });
    });

    it("should override existing fields", () => {
      const provider = new TestProvider({ apiKey: "old-key", model: "old-model" });

      provider.setConfig({ apiKey: "new-key" });

      expect(provider.getConfig()).toEqual({
        apiKey: "new-key",
        model: "old-model",
      });
    });

    it("should accept empty object", () => {
      const provider = new TestProvider({ apiKey: "test" });
      const originalConfig = provider.getConfig();

      provider.setConfig({});

      expect(provider.getConfig()).toEqual(originalConfig);
    });

    it("should handle multiple updates", () => {
      const provider = new TestProvider();

      provider.setConfig({ apiKey: "key1" });
      provider.setConfig({ model: "model1" });
      provider.setConfig({ baseUrl: "https://test.com" });

      expect(provider.getConfig()).toEqual({
        apiKey: "key1",
        model: "model1",
        baseUrl: "https://test.com",
      });
    });

    it("should preserve other fields when updating one field", () => {
      const provider = new TestProvider({
        apiKey: "key",
        model: "model",
        baseUrl: "https://test.com",
      });

      provider.setConfig({ model: "new-model" });

      expect(provider.getConfig()).toEqual({
        apiKey: "key",
        model: "new-model",
        baseUrl: "https://test.com",
      });
    });
  });

  describe("abstract methods", () => {
    it("should require getName implementation", () => {
      const provider = new TestProvider();
      expect(typeof provider.getName).toBe("function");
      expect(provider.getName()).toBe("test-provider");
    });

    it("should require executeQuery implementation", async () => {
      const provider = new TestProvider();
      expect(typeof provider.executeQuery).toBe("function");

      const generator = provider.executeQuery({
        prompt: "test",
        projectDirectory: "/test",
      });
      const result = await generator.next();

      expect(result.value).toEqual({ type: "text", text: "test response" });
    });

    it("should require detectInstallation implementation", async () => {
      const provider = new TestProvider();
      expect(typeof provider.detectInstallation).toBe("function");

      const status = await provider.detectInstallation();
      expect(status).toHaveProperty("installed");
    });

    it("should require getAvailableModels implementation", () => {
      const provider = new TestProvider();
      expect(typeof provider.getAvailableModels).toBe("function");

      const models = provider.getAvailableModels();
      expect(Array.isArray(models)).toBe(true);
      expect(models.length).toBeGreaterThan(0);
    });
  });
});