import { BackendUnavailableError, emptyTokenUsage, emptyBackendResult, DEFAULT_BACKEND_CONFIG } from "../backends/types.js";
import { OllamaLocalBackend } from "../backends/ollama-local.js";
import { OllamaCloudBackend } from "../backends/ollama-cloud.js";
import { OpencodeBackend } from "../backends/opencode.js";

describe("BackendUnavailableError", () => {
  it("includes backend name in message", () => {
    const err = new BackendUnavailableError("ollama-local");
    expect(err.message).toContain("ollama-local");
    expect(err.backendName).toBe("ollama-local");
  });

  it("includes agent name when provided", () => {
    const err = new BackendUnavailableError("opencode", "executor");
    expect(err.agentName).toBe("executor");
    expect(err.message).toContain("executor");
  });
});

describe("emptyTokenUsage", () => {
  it("returns zeroed usage", () => {
    const usage = emptyTokenUsage();
    expect(usage.input_tokens).toBe(0);
    expect(usage.output_tokens).toBe(0);
    expect(usage.total_tokens).toBe(0);
    expect(usage.estimated_cost_usd).toBe(0);
  });
});

describe("emptyBackendResult", () => {
  it("returns failed result with no artifacts", () => {
    const result = emptyBackendResult("something failed");
    expect(result.success).toBe(false);
    expect(result.error).toBe("something failed");
    expect(result.artifacts).toEqual([]);
    expect(result.decisions).toEqual([]);
    expect(result.escalations).toEqual([]);
  });

  it("returns result without error when no message provided", () => {
    const result = emptyBackendResult();
    expect(result.success).toBe(false);
    expect(result.error).toBeUndefined();
  });
});

describe("DEFAULT_BACKEND_CONFIG", () => {
  it("has auto provider by default", () => {
    expect(DEFAULT_BACKEND_CONFIG.provider).toBe("auto");
  });

  it("has opencode agent backend enabled", () => {
    expect(DEFAULT_BACKEND_CONFIG.agent_backends.opencode?.enabled).toBe(true);
  });

  it("has ollama-local and ollama-cloud llm backends", () => {
    expect(DEFAULT_BACKEND_CONFIG.llm_backends["ollama-local"]).toBeDefined();
    expect(DEFAULT_BACKEND_CONFIG.llm_backends["ollama-cloud"]).toBeDefined();
  });
});

describe("OllamaLocalBackend", () => {
  it("has correct name and type", () => {
    const backend = new OllamaLocalBackend();
    expect(backend.name).toBe("ollama-local");
    expect(backend.type).toBe("llm");
  });

  it("returns false when local Ollama is not available", async () => {
    const backend = new OllamaLocalBackend({
      base_url: "http://localhost:1",
      model_profile: "balanced",
    });
    const available = await backend.isAvailable();
    expect(available).toBe(false);
  });

  it("uses default config when none provided", () => {
    const backend = new OllamaLocalBackend();
    expect(backend).toBeDefined();
  });
});

describe("OllamaCloudBackend", () => {
  it("has correct name and type", () => {
    const backend = new OllamaCloudBackend();
    expect(backend.name).toBe("ollama-cloud");
    expect(backend.type).toBe("llm");
  });

  it("returns false when no base_url configured", async () => {
    const backend = new OllamaCloudBackend({
      base_url: "",
      api_key_env: "NONEXISTENT_KEY",
      model_profile: "quality",
      timeout_ms: 5000,
    });
    const available = await backend.isAvailable();
    expect(available).toBe(false);
  });

  it("returns false when no API key available", async () => {
    const backend = new OllamaCloudBackend({
      base_url: "https://example.com",
      api_key_env: "NONEXISTENT_CI_KEY_12345",
      model_profile: "quality",
      timeout_ms: 5000,
    });
    const available = await backend.isAvailable();
    expect(available).toBe(false);
  });
});

describe("OpencodeBackend", () => {
  it("has correct name and type", () => {
    const backend = new OpencodeBackend();
    expect(backend.name).toBe("opencode");
    expect(backend.type).toBe("agent");
  });

  it("returns false when opencode is not installed", async () => {
    const backend = new OpencodeBackend({
      enabled: true,
      executable: "nonexistent-opencode-binary-xyz",
    });
    const available = await backend.isAvailable();
    expect(available).toBe(false);
  });
});