import { describe, it, expect, vi, beforeEach } from 'vitest';
import type { ContainerSpec } from '../src/services/orchestrator.js';

// Mock @kubernetes/client-node before imports
vi.mock('@kubernetes/client-node', () => {
  const handlers = new Map<string, { resolve: unknown; reject?: unknown }>();

  function setHandler(key: string, resolveVal: unknown, rejectVal?: unknown) {
    handlers.set(key, { resolve: resolveVal, reject: rejectVal });
  }

  function getHandler(key: string) {
    return handlers.get(key);
  }

  function clearHandlers() {
    handlers.clear();
  }

  const mockCore = {
    listNamespace: vi.fn(async () => {
      const h = getHandler('listNamespace');
      if (h?.reject) throw h.reject;
      return h?.resolve ?? { items: [] };
    }),
    createNamespacedPod: vi.fn(async (params: { namespace: string; body: { metadata: { name: string } } }) => {
      const h = getHandler('createNamespacedPod');
      if (h?.reject) throw h.reject;
      return h?.resolve ?? params.body;
    }),
    readNamespacedPod: vi.fn(async (params: { name: string }) => {
      const h = getHandler(`readNamespacedPod:${params.name}`);
      if (h?.reject) throw h.reject;
      return h?.resolve;
    }),
    deleteNamespacedPod: vi.fn(async (params: { name: string }) => {
      const h = getHandler(`deleteNamespacedPod:${params.name}`);
      if (h?.reject) throw h.reject;
      return h?.resolve ?? {};
    }),
    listNamespacedPod: vi.fn(async () => {
      const h = getHandler('listNamespacedPod');
      if (h?.reject) throw h.reject;
      return h?.resolve ?? { items: [] };
    }),
    readNamespace: vi.fn(async (params: { name: string }) => {
      const h = getHandler(`readNamespace:${params.name}`);
      if (h?.reject) throw h.reject;
      return h?.resolve ?? {};
    }),
    createNamespace: vi.fn(async () => {
      const h = getHandler('createNamespace');
      if (h?.reject) throw h.reject;
      return h?.resolve ?? {};
    }),
  };

  class MockKubeConfig {
    loadFromDefault = vi.fn();
    setCurrentContext = vi.fn();
    getContexts = vi.fn(() => []);
    getCurrentContext = vi.fn(() => 'default');
    makeApiClient = vi.fn(() => mockCore);
  }

  // Track the live Exec/Attach instances so tests can program their vi.fn()s
  // (each K8sOfficialClient constructs fresh ones).
  const instances: { exec?: { exec: ReturnType<typeof vi.fn> }; attach?: { attach: ReturnType<typeof vi.fn> } } = {};

  class MockExec {
    exec = vi.fn();
    constructor() {
      instances.exec = this;
    }
  }

  class MockAttach {
    attach = vi.fn();
    constructor() {
      instances.attach = this;
    }
  }

  class MockLog {
    log = vi.fn();
  }

  return {
    KubeConfig: MockKubeConfig,
    CoreV1Api: class {},
    Exec: MockExec,
    Attach: MockAttach,
    Log: MockLog,
    // Export test helpers
    __testHelpers: { setHandler, getHandler, clearHandlers, mockCore, instances },
  };
});

// Import after mock
import { KubernetesOrchestrator, httpStatusOf } from '../src/services/k8s/kubernetes-orchestrator.js';
// eslint-disable-next-line @typescript-eslint/no-explicit-any
const k8sMock = await import('@kubernetes/client-node') as any;
const { setHandler, clearHandlers, mockCore } = k8sMock.__testHelpers;

const testSpec: ContainerSpec = {
  image: 'mysources.co.uk/michal/mcpctl-node-runner:latest',
  name: 'my-server',
  env: { PORT: '3000' },
  containerPort: 3000,
};

const podRunning = {
  metadata: {
    name: 'my-server',
    namespace: 'mcpctl-servers',
    creationTimestamp: '2026-01-01T00:00:00Z',
    labels: { 'mcpctl.managed': 'true' },
  },
  status: {
    phase: 'Running',
    podIP: '10.42.0.15',
    containerStatuses: [{
      state: { running: { startedAt: '2026-01-01T00:00:00Z' } },
    }],
  },
  spec: {
    containers: [{ name: 'my-server', ports: [{ containerPort: 3000 }] }],
  },
};

const podPending = {
  metadata: {
    name: 'my-server',
    namespace: 'mcpctl-servers',
    creationTimestamp: '2026-01-01T00:00:00Z',
  },
  status: {
    phase: 'Pending',
    containerStatuses: [{
      state: { waiting: { reason: 'ContainerCreating' } },
    }],
  },
  spec: {
    containers: [{ name: 'my-server' }],
  },
};

describe('KubernetesOrchestrator', () => {
  let orch: KubernetesOrchestrator;

  beforeEach(() => {
    clearHandlers();
    vi.clearAllMocks();
    orch = new KubernetesOrchestrator({ serversNamespace: 'mcpctl-servers' });
  });

  describe('ping', () => {
    it('returns true on successful API call', async () => {
      setHandler('listNamespace', { items: [] });
      expect(await orch.ping()).toBe(true);
    });

    it('returns false on error', async () => {
      setHandler('listNamespace', undefined, new Error('connection refused'));
      expect(await orch.ping()).toBe(false);
    });
  });

  describe('pullImage', () => {
    it('is a no-op for K8s', async () => {
      await expect(orch.pullImage('some-image:latest')).resolves.toBeUndefined();
    });
  });

  describe('createContainer', () => {
    it('creates a pod and returns container info', async () => {
      // ensureNamespace
      setHandler('readNamespace:mcpctl-servers', {});
      // createPod returns the pod
      setHandler('createNamespacedPod', podRunning);
      // inspectContainer after create
      setHandler('readNamespacedPod:my-server', podRunning);

      const info = await orch.createContainer(testSpec);
      expect(info.containerId).toBe('my-server');
      expect(info.state).toBe('running');
      expect(info.port).toBe(3000);
      expect(info.ip).toBe('10.42.0.15');
    });

    it('throws on API error', async () => {
      setHandler('readNamespace:mcpctl-servers', {});
      setHandler('createNamespacedPod', undefined, new Error('pod already exists'));

      await expect(orch.createContainer(testSpec)).rejects.toThrow('pod already exists');
    });
  });

  describe('inspectContainer', () => {
    it('returns running container info with pod IP', async () => {
      setHandler('readNamespacedPod:my-server', podRunning);

      const info = await orch.inspectContainer('my-server');
      expect(info.state).toBe('running');
      expect(info.name).toBe('my-server');
      expect(info.ip).toBe('10.42.0.15');
      expect(info.port).toBe(3000);
    });

    it('maps pending state correctly', async () => {
      setHandler('readNamespacedPod:my-server', podPending);

      const info = await orch.inspectContainer('my-server');
      expect(info.state).toBe('starting');
    });

    it('throws when pod not found', async () => {
      setHandler('readNamespacedPod:missing', undefined, { statusCode: 404, message: 'not found' });

      await expect(orch.inspectContainer('missing')).rejects.toBeDefined();
    });
  });

  describe('stopContainer', () => {
    it('deletes the pod', async () => {
      setHandler('deleteNamespacedPod:my-server', {});
      await expect(orch.stopContainer('my-server')).resolves.toBeUndefined();
    });
  });

  describe('removeContainer', () => {
    it('deletes the pod successfully', async () => {
      setHandler('deleteNamespacedPod:my-server', {});
      await expect(orch.removeContainer('my-server')).resolves.toBeUndefined();
    });

    it('ignores 404 (already deleted)', async () => {
      setHandler('deleteNamespacedPod:my-server', undefined, { statusCode: 404 });
      await expect(orch.removeContainer('my-server')).resolves.toBeUndefined();
    });

    it('throws on other errors', async () => {
      setHandler('deleteNamespacedPod:my-server', undefined, { statusCode: 403, message: 'forbidden' });
      await expect(orch.removeContainer('my-server')).rejects.toBeDefined();
    });
  });

  describe('listContainers', () => {
    it('lists managed pods', async () => {
      setHandler('listNamespacedPod', { items: [podRunning] });

      const containers = await orch.listContainers();
      expect(containers).toHaveLength(1);
      expect(containers[0]!.containerId).toBe('my-server');
      expect(containers[0]!.state).toBe('running');
      expect(containers[0]!.ip).toBe('10.42.0.15');

      expect(mockCore.listNamespacedPod).toHaveBeenCalledWith(
        expect.objectContaining({ labelSelector: 'mcpctl.managed=true' }),
      );
    });

    it('returns empty when no pods', async () => {
      setHandler('listNamespacedPod', { items: [] });
      const containers = await orch.listContainers();
      expect(containers).toEqual([]);
    });
  });

  describe('ensureNamespace', () => {
    it('does nothing if namespace exists', async () => {
      setHandler('readNamespace:test-ns', {});
      await expect(orch.ensureNamespace('test-ns')).resolves.toBeUndefined();
      expect(mockCore.createNamespace).not.toHaveBeenCalled();
    });

    it('creates namespace if not found', async () => {
      setHandler('readNamespace:new-ns', undefined, { statusCode: 404 });
      setHandler('createNamespace', {});
      await expect(orch.ensureNamespace('new-ns')).resolves.toBeUndefined();
      expect(mockCore.createNamespace).toHaveBeenCalled();
    });

    it('handles conflict (namespace already created by another process)', async () => {
      setHandler('readNamespace:new-ns', undefined, { statusCode: 404 });
      setHandler('createNamespace', undefined, { statusCode: 409, message: 'already exists' });
      await expect(orch.ensureNamespace('new-ns')).resolves.toBeUndefined();
    });
  });

  describe('getNamespace', () => {
    it('returns configured namespace', () => {
      expect(orch.getNamespace()).toBe('mcpctl-servers');
    });

    it('defaults to mcpctl-servers', () => {
      const defaultOrch = new KubernetesOrchestrator();
      expect(defaultOrch.getNamespace()).toBe('mcpctl-servers');
    });
  });

  describe('pod IP extraction', () => {
    it('extracts podIP from status', async () => {
      setHandler('readNamespacedPod:my-server', podRunning);
      const info = await orch.inspectContainer('my-server');
      expect(info.ip).toBe('10.42.0.15');
    });

    it('returns undefined ip when no podIP', async () => {
      const podWithoutIP = {
        ...podRunning,
        status: { ...podRunning.status, podIP: undefined },
      };
      setHandler('readNamespacedPod:my-server', podWithoutIP);
      const info = await orch.inspectContainer('my-server');
      expect(info.ip).toBeUndefined();
    });
  });

  describe('manifest security', () => {
    it('creates pods with security hardening', async () => {
      setHandler('readNamespace:mcpctl-servers', {});
      setHandler('createNamespacedPod', podRunning);
      setHandler('readNamespacedPod:my-server', podRunning);

      await orch.createContainer(testSpec);

      const createCall = mockCore.createNamespacedPod.mock.calls[0]![0];
      const container = createCall.body.spec.containers[0];
      expect(container.securityContext.runAsNonRoot).toBe(false);
      expect(container.securityContext.readOnlyRootFilesystem).toBe(false);
      expect(container.securityContext.allowPrivilegeEscalation).toBe(false);
      expect(container.securityContext.capabilities.drop).toEqual(['ALL']);
      expect(container.securityContext.seccompProfile.type).toBe('RuntimeDefault');
    });

    it('creates pods with automountServiceAccountToken disabled', async () => {
      setHandler('readNamespace:mcpctl-servers', {});
      setHandler('createNamespacedPod', podRunning);
      setHandler('readNamespacedPod:my-server', podRunning);

      await orch.createContainer(testSpec);

      const createCall = mockCore.createNamespacedPod.mock.calls[0]![0];
      expect(createCall.body.spec.automountServiceAccountToken).toBe(false);
    });

    it('creates pods with stdin enabled for STDIO servers', async () => {
      setHandler('readNamespace:mcpctl-servers', {});
      setHandler('createNamespacedPod', podRunning);
      setHandler('readNamespacedPod:my-server', podRunning);

      await orch.createContainer(testSpec);

      const createCall = mockCore.createNamespacedPod.mock.calls[0]![0];
      expect(createCall.body.spec.containers[0].stdin).toBe(true);
    });
  });

  describe('context enforcement', () => {
    it('sets context when configured', () => {
      const _orch = new KubernetesOrchestrator({ context: 'default' });
      // The mock KubeConfig.setCurrentContext should have been called
      // This verifies the safety mechanism works
      expect(_orch.getNamespace()).toBe('mcpctl-servers');
    });
  });
});

describe('httpStatusOf', () => {
  it('reads .code, which is what client-node v1 ApiException actually sets', () => {
    // The bug this exists for: reading only .statusCode returned undefined, so
    // an expected 404 was rethrown and a first-start PVC create never happened.
    expect(httpStatusOf({ code: 404 })).toBe(404);
    expect(httpStatusOf({ code: 409 })).toBe(409);
  });

  it('still reads the pre-1.0 HttpError shapes', () => {
    expect(httpStatusOf({ statusCode: 404 })).toBe(404);
    expect(httpStatusOf({ response: { statusCode: 409 } })).toBe(409);
  });

  it('falls back to parsing the rendered message', () => {
    expect(httpStatusOf(new Error('HTTP-Code: 403\nMessage: Unknown API Status Code!'))).toBe(403);
  });

  it('returns undefined when there is no status to find', () => {
    expect(httpStatusOf(new Error('socket hang up'))).toBeUndefined();
    expect(httpStatusOf({ code: 'ECONNREFUSED' })).toBeUndefined();
  });
});

// ── mcpctl#114: interactive-session death signals, restartCount, 409-adopt ──

import { EventEmitter } from 'node:events';

function makeFakeWs(): EventEmitter & { close: ReturnType<typeof vi.fn> } {
  const ws = new EventEmitter() as EventEmitter & { close: ReturnType<typeof vi.fn> };
  ws.close = vi.fn();
  return ws;
}

const podRestarted = {
  ...podRunning,
  status: {
    ...podRunning.status,
    containerStatuses: [{
      state: { running: { startedAt: '2026-01-02T00:00:00Z' } },
      restartCount: 3,
      lastState: { terminated: { reason: 'OOMKilled', exitCode: 137 } },
    }],
  },
};

const podTerminated = {
  ...podRunning,
  status: {
    phase: 'Failed',
    containerStatuses: [{
      state: { terminated: { reason: 'Error', exitCode: 1 } },
      restartCount: 1,
    }],
  },
};

describe('KubernetesOrchestrator interactive sessions (mcpctl#114)', () => {
  let orch: KubernetesOrchestrator;

  beforeEach(() => {
    clearHandlers();
    vi.clearAllMocks();
    orch = new KubernetesOrchestrator({ serversNamespace: 'mcpctl-servers' });
  });

  it("execInteractive: ws 'close' ends stdout so the consumer sees the death", async () => {
    setHandler('readNamespacedPod:my-server', podRunning);
    const ws = makeFakeWs();
    k8sMock.__testHelpers.instances.exec!.exec.mockResolvedValue(ws);

    const iexec = await orch.execInteractive!('my-server', ['node', 'index.js']);
    iexec.stdout.resume(); // PassThrough only emits 'end' once it is being read
    const ended = new Promise<void>((resolve) => iexec.stdout.on('end', resolve));
    ws.emit('close');
    await expect(ended).resolves.toBeUndefined();
  });

  it("execInteractive: ws 'error' also ends stdout, and close() closes the ws", async () => {
    setHandler('readNamespacedPod:my-server', podRunning);
    const ws = makeFakeWs();
    k8sMock.__testHelpers.instances.exec!.exec.mockResolvedValue(ws);

    const iexec = await orch.execInteractive!('my-server', ['node']);
    iexec.stdout.resume();
    const ended = new Promise<void>((resolve) => iexec.stdout.on('end', resolve));
    ws.emit('error', new Error('abnormal closure'));
    await expect(ended).resolves.toBeUndefined();

    iexec.close();
    expect(ws.close).toHaveBeenCalled();
  });

  it("attachInteractive: ws 'close' ends stdout (first-ever attach coverage)", async () => {
    setHandler('readNamespacedPod:my-server', podRunning);
    const ws = makeFakeWs();
    k8sMock.__testHelpers.instances.attach!.attach.mockResolvedValue(ws);

    const iexec = await orch.attachInteractive!('my-server');
    iexec.stdout.resume();
    const ended = new Promise<void>((resolve) => iexec.stdout.on('end', resolve));
    ws.emit('close');
    await expect(ended).resolves.toBeUndefined();
    expect(k8sMock.__testHelpers.instances.attach!.attach).toHaveBeenCalledOnce();
  });

  it('inspectContainer surfaces restartCount and startedAt', async () => {
    setHandler('readNamespacedPod:my-server', podRestarted);
    const info = await orch.inspectContainer('my-server');
    expect(info.state).toBe('running');
    expect(info.restartCount).toBe(3);
    expect(info.startedAt).toEqual(new Date('2026-01-02T00:00:00Z'));
  });

  it('createContainer ADOPTS an alive pod on 409 instead of throwing', async () => {
    setHandler('readNamespace:mcpctl-servers', {});
    setHandler('createNamespacedPod', undefined, { code: 409 });
    setHandler('readNamespacedPod:my-server', podRestarted);

    const info = await orch.createContainer(testSpec);
    expect(info.containerId).toBe('my-server');
    expect(info.state).toBe('running');
    expect(mockCore.deleteNamespacedPod).not.toHaveBeenCalled();
  });

  it('createContainer replaces a genuinely dead pod on 409', async () => {
    setHandler('readNamespace:mcpctl-servers', {});
    setHandler('createNamespacedPod', undefined, { code: 409 });
    setHandler('readNamespacedPod:my-server', podTerminated);
    setHandler('deleteNamespacedPod:my-server', {});

    const promise = orch.createContainer(testSpec);
    // Give it a tick to inspect + delete, then flip the world: pod is gone,
    // create succeeds.
    await new Promise((r) => setTimeout(r, 50));
    // The gone-wait loop polls once per second: serve 404 so it breaks, then
    // restore the pod before the post-create inspect (~500ms later) runs.
    setHandler('readNamespacedPod:my-server', undefined, { code: 404 });
    setHandler('createNamespacedPod', podRunning);
    setTimeout(() => setHandler('readNamespacedPod:my-server', podRunning), 1200);

    const info = await promise;
    expect(info.state).toBe('running');
    expect(mockCore.deleteNamespacedPod).toHaveBeenCalled();
    expect(mockCore.createNamespacedPod).toHaveBeenCalledTimes(2);
  });

  it('createContainer still throws on non-409 errors', async () => {
    setHandler('readNamespace:mcpctl-servers', {});
    setHandler('createNamespacedPod', undefined, { code: 500 });
    await expect(orch.createContainer(testSpec)).rejects.toBeTruthy();
  });
});