import { tap, expect } from '@git.zone/tstest/tapbundle';
import { RustSecurityBridge, BridgeState } from '../ts/security/classes.rustsecuritybridge.js';
import type { IBridgeResilienceConfig } from '../ts/security/classes.rustsecuritybridge.js';

// Use fast backoff settings for testing
const TEST_CONFIG: Partial<IBridgeResilienceConfig> = {
  maxRestartAttempts: 3,
  healthCheckIntervalMs: 60_000, // long interval so health checks don't interfere
  restartBackoffBaseMs: 100,
  restartBackoffMaxMs: 500,
  healthCheckTimeoutMs: 2_000,
};

tap.test('Resilience - should start in Idle state', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
  const bridge = RustSecurityBridge.getInstance();
  expect(bridge.state).toEqual(BridgeState.Idle);
});

tap.test('Resilience - state transitions: Idle -> Starting -> Running', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
  const bridge = RustSecurityBridge.getInstance();

  const transitions: Array<{ oldState: string; newState: string }> = [];
  bridge.on('stateChange', (evt: { oldState: string; newState: string }) => {
    transitions.push(evt);
  });

  const ok = await bridge.start();
  if (!ok) {
    console.log('WARNING: Rust binary not available — skipping resilience start tests');
    return;
  }

  // We should have seen Idle -> Starting -> Running
  expect(transitions.length).toBeGreaterThanOrEqual(2);
  expect(transitions[0].oldState).toEqual(BridgeState.Idle);
  expect(transitions[0].newState).toEqual(BridgeState.Starting);
  expect(transitions[1].oldState).toEqual(BridgeState.Starting);
  expect(transitions[1].newState).toEqual(BridgeState.Running);
  expect(bridge.state).toEqual(BridgeState.Running);
});

tap.test('Resilience - deliberate stop transitions to Stopped', async () => {
  const bridge = RustSecurityBridge.getInstance();
  if (!bridge.running) {
    console.log('SKIP: bridge not running');
    return;
  }

  const transitions: Array<{ oldState: string; newState: string }> = [];
  bridge.on('stateChange', (evt: { oldState: string; newState: string }) => {
    transitions.push(evt);
  });

  await bridge.stop();
  expect(bridge.state).toEqual(BridgeState.Stopped);

  // Deliberate stop should NOT trigger restart
  // Wait a bit to ensure no restart happens
  await new Promise(resolve => setTimeout(resolve, 300));
  expect(bridge.state).toEqual(BridgeState.Stopped);

  bridge.removeAllListeners('stateChange');
});

tap.test('Resilience - commands throw descriptive errors when not running', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
  const bridge = RustSecurityBridge.getInstance();

  // Idle state
  try {
    await bridge.ping();
    expect(true).toBeFalse(); // Should not reach
  } catch (err) {
    expect((err as Error).message).toInclude('not been started');
  }

  // Stopped state
  const ok = await bridge.start();
  if (ok) {
    await bridge.stop();
    try {
      await bridge.ping();
      expect(true).toBeFalse();
    } catch (err) {
      expect((err as Error).message).toInclude('stopped');
    }
  }
});

tap.test('Resilience - restart after stop and fresh start', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
  const bridge = RustSecurityBridge.getInstance();

  const ok = await bridge.start();
  if (!ok) {
    console.log('SKIP: Rust binary not available');
    return;
  }
  expect(bridge.state).toEqual(BridgeState.Running);

  // Stop
  await bridge.stop();
  expect(bridge.state).toEqual(BridgeState.Stopped);

  // Start again
  const ok2 = await bridge.start();
  expect(ok2).toBeTrue();
  expect(bridge.state).toEqual(BridgeState.Running);

  // Commands should work
  const pong = await bridge.ping();
  expect(pong).toBeTrue();

  await bridge.stop();
});

tap.test('Resilience - stateChange events emitted correctly', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
  const bridge = RustSecurityBridge.getInstance();

  const events: Array<{ oldState: string; newState: string }> = [];
  bridge.on('stateChange', (evt: { oldState: string; newState: string }) => {
    events.push(evt);
  });

  const ok = await bridge.start();
  if (!ok) {
    console.log('SKIP: Rust binary not available');
    return;
  }

  await bridge.stop();

  // Verify the full lifecycle: Idle->Starting->Running->Stopped
  const stateSequence = events.map(e => e.newState);
  expect(stateSequence).toContain(BridgeState.Starting);
  expect(stateSequence).toContain(BridgeState.Running);
  expect(stateSequence).toContain(BridgeState.Stopped);

  bridge.removeAllListeners('stateChange');
});

tap.test('Resilience - configure sets resilience parameters', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure({
    maxRestartAttempts: 10,
    healthCheckIntervalMs: 60_000,
  });
  // Just verify no errors — config is private, but we can verify
  // by the behavior in other tests
  const bridge = RustSecurityBridge.getInstance();
  expect(bridge).toBeTruthy();
});

tap.test('Resilience - resetInstance creates fresh singleton', async () => {
  RustSecurityBridge.resetInstance();
  const bridge1 = RustSecurityBridge.getInstance();
  RustSecurityBridge.resetInstance();
  const bridge2 = RustSecurityBridge.getInstance();
  // They should be different instances (we can't compare directly since
  // resetInstance nulls the static, and getInstance creates new)
  expect(bridge2.state).toEqual(BridgeState.Idle);
});

tap.test('Resilience - cleanup', async () => {
  RustSecurityBridge.resetInstance();
  RustSecurityBridge.configure(TEST_CONFIG);
});

export default tap.start();