import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import { ScenarioService } from '../src/scenario/ScenarioService.js';
import { getScenarioRuntime, RudderClient } from '../src/client/RudderClient.js';
import { createFakeTokenStore } from './helpers/FakeTokenStore.js';
import { effect } from './helpers/plan.js';
import { RudderHttpError } from '../src/client/RudderError.js';
import type { NotificationEffect, StoreOfferEffect, WaitEffect } from '../src/index.js';
import type { PendingEffect } from '../src/generated/scenarios.js';

async function createClientWithScenario(): Promise<{ client: RudderClient; scenarios: ScenarioService }> {
  const client = new RudderClient({
    baseUrl: 'https://api.test.rudder.build',
    projectKey: 'test-key',
    tokenStore: createFakeTokenStore(),
    runtime: { loginEvent: null },
  });
  return { client, scenarios: await getScenarioRuntime(client) };
}

function jsonResponse(body: unknown, status = 200): Response {
  return new Response(JSON.stringify(body), { status });
}

function stubFetch(handler: (path: string, method: string, body: unknown) => Response | Promise<Response>): void {
  vi.stubGlobal('fetch', vi.fn().mockImplementation((url: string, init?: RequestInit) => {
    const parsed = new URL(url);
    const method = (init?.method ?? 'GET').toUpperCase();
    const body = init?.body ? JSON.parse(init.body as string) : undefined;
    return Promise.resolve(handler(parsed.pathname, method, body));
  }));
}

describe('ScenarioService', () => {
  beforeEach(() => {
    vi.stubGlobal('crypto', {
      randomUUID: () => '00000000-0000-4000-a000-000000000001',
    });
  });

  afterEach(() => {
    vi.useRealTimers();
    vi.unstubAllGlobals();
  });

  describe('send (trigger)', () => {
    it('calls POST /sdk/v1/scenarios/trigger and emits effects', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onNotification = vi.fn();
      client.effects.onNotification(onNotification);

      stubFetch((path, method) => {
        if (method === 'POST' && path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({
            effects: [effect('notification', { title: 'Hi', message: 'Welcome' })],
          });
        }
        return jsonResponse({});
      });

      const response = await scenarios.send('level_complete');

      expect(response.effects).toHaveLength(1);
      expect(scenarios.isRunning).toBe(true);
      expect(onNotification).toHaveBeenCalledOnce();
      expect(onNotification.mock.calls[0][0].title).toBe('Hi');
      expect(onNotification.mock.calls[0][0].message).toBe('Welcome');
    });
  });

  describe('effect emission', () => {
    it('notification node fires onNotification', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onNotif = vi.fn();
      client.effects.onNotification(onNotif);
      stubFetch(() => jsonResponse({ effects: [effect('notification')] }));
      await scenarios.send('test');
      expect(onNotif).toHaveBeenCalledOnce();
    });

    it('store node fires onStoreOffer', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onStore = vi.fn();
      client.effects.onStoreOffer(onStore);
      stubFetch((path) => {
        if (path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({
            effects: [effect('store', { storeSlug: 'starter', message: 'Buy!' })],
          });
        }
        if (path === '/sdk/v1/stores/starter') {
          return jsonResponse({ slug: 'starter', name: 'Starter', offers: [{ id: 'pack_1', slug: 'pack-1', name: 'Pack' }] });
        }
        return jsonResponse({});
      });
      await scenarios.send('test');
      await vi.waitFor(() => expect(onStore).toHaveBeenCalledOnce());
      const offer = onStore.mock.calls[0][0] as StoreOfferEffect;
      expect(offer.message).toBe('Buy!');
      expect(offer.store.slug).toBe('starter');
    });

    it('wait node fires onWait', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onWait = vi.fn();
      client.effects.onWait(onWait);
      const deadline = new Date(Date.now() + 60_000).toISOString();
      stubFetch(() => jsonResponse({
        effects: [effect('wait', {}, { waitDeadline: deadline })],
      }));
      await scenarios.send('test');
      expect(onWait).toHaveBeenCalledOnce();
      expect(onWait.mock.calls[0][0].deadlineUtc).toBeInstanceOf(Date);
    });

    it('leaderboard node fires onLeaderboard', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onLb = vi.fn();
      client.effects.onLeaderboard(onLb);
      stubFetch(() => jsonResponse({ effects: [effect('leaderboard')] }));
      await scenarios.send('test');
      expect(onLb).toHaveBeenCalledOnce();
    });

    it('quest node dispatches onQuest', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onQuest = vi.fn();
      client.effects.onQuest(onQuest);
      stubFetch(() => jsonResponse({
        effects: [effect('quest', { name: 'Daily', objectives: [{ objectiveId: 'kills', target: 10 }] })],
      }));
      await scenarios.send('test');
      expect(onQuest).toHaveBeenCalledOnce();
      expect(onQuest.mock.calls[0][0].name).toBe('Daily');
      expect(scenarios.isRunning).toBe(true);
    });

    it('battlepass node dispatches onBattlePass', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onBp = vi.fn();
      client.effects.onBattlePass(onBp);
      stubFetch(() => jsonResponse({ effects: [effect('battlepass', { premiumPrice: 100 })] }));
      await scenarios.send('test');
      expect(onBp).toHaveBeenCalledOnce();
      expect(scenarios.isRunning).toBe(true);
    });

    it('battlepass_level node dispatches onBattlePassLevel', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onLevel = vi.fn();
      client.effects.onBattlePassLevel(onLevel);
      stubFetch(() => jsonResponse({
        effects: [effect('battlepass_level', { levelNumber: 3 })],
      }));
      await scenarios.send('test');
      expect(onLevel).toHaveBeenCalledOnce();
      expect(onLevel.mock.calls[0][0].level).toBe(3);
    });

    it('unsupported node type fails the run and surfaces onScenarioFailed', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
      const onFailed = vi.fn();
      client.effects.onScenarioFailed(onFailed);
      stubFetch(() => jsonResponse({ effects: [effect('unknown_type')] }));
      await scenarios.send('test');
      expect(warn).toHaveBeenCalledWith(
        expect.stringContaining('Unsupported scenario node type'),
      );
      expect(onFailed).toHaveBeenCalledOnce();
      expect(scenarios.isRunning).toBe(false);
      warn.mockRestore();
    });
  });

  describe('callback continuation', () => {
    it('completing an effect posts callback and emits the next effect', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onNotif = vi.fn();
      client.effects.onNotification(onNotif);
      const first = effect('notification', { message: 'one' }, { nodeId: 'n1' });
      const second = effect('notification', { message: 'two' }, { nodeId: 'n2' });

      stubFetch((path, method) => {
        if (method === 'POST' && path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [first] });
        }
        if (method === 'POST' && path === '/sdk/v1/scenarios/callback') {
          return jsonResponse({ effect: second });
        }
        return jsonResponse({});
      });

      await scenarios.send('test');
      expect(onNotif).toHaveBeenCalledOnce();
      const session = onNotif.mock.calls[0][0] as NotificationEffect;
      await session.done();
      expect(onNotif).toHaveBeenCalledTimes(2);
      expect(onNotif.mock.calls[1][0].message).toBe('two');

      const fetchMock = vi.mocked(fetch);
      const callbackCall = fetchMock.mock.calls.find((call) => {
        const url = String(call[0]);
        return url.includes('/sdk/v1/scenarios/callback');
      });
      expect(JSON.parse(callbackCall![1]!.body as string)).toEqual({
        scenarioSlug: 'scenario-1',
        nodeId: 'n1',
        handle: 'output',
        runId: 'run-1',
      });
    });

    it('completing the last effect emits onScenarioCompleted', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onCompleted = vi.fn();
      const onNotif = vi.fn();
      client.effects.onScenarioCompleted(onCompleted);
      client.effects.onNotification(onNotif);
      stubFetch((path) => {
        if (path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [effect('notification')] });
        }
        return jsonResponse({});
      });
      await scenarios.send('test');
      await (onNotif.mock.calls[0][0] as NotificationEffect).done();
      expect(onCompleted).toHaveBeenCalledOnce();
      expect(onCompleted.mock.calls[0][0]).toEqual({
        runId: 'run-1',
        scenarioSlug: 'scenario-1',
      });
      expect(scenarios.isRunning).toBe(false);
    });
  });

  describe('pending dedup', () => {
    it('does not re-emit an effect with the same runId and nodeId', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onNotification = vi.fn();
      client.effects.onNotification(onNotification);
      const pending = effect('notification', { message: 'once' });
      stubFetch(() => jsonResponse({ effects: [pending] }));
      await scenarios.send('first-event');
      await scenarios.send('second-event');
      expect(onNotification).toHaveBeenCalledTimes(1);
      expect(scenarios.isRunning).toBe(true);
    });
  });

  describe('waitDeadline timer', () => {
    it('polls pending at waitDeadline and emits the next effect', async () => {
      vi.useFakeTimers();
      const { client, scenarios } = await createClientWithScenario();
      const onWait = vi.fn();
      const onNotif = vi.fn();
      client.effects.onWait(onWait);
      client.effects.onNotification(onNotif);

      const deadline = new Date(Date.now() + 5_000).toISOString();
      const wait = effect('wait', {}, { waitDeadline: deadline, nodeId: 'wait-1' });
      const next = effect('notification', { message: 'after wait' }, { nodeId: 'n2' });
      let pending: PendingEffect[] = [wait];

      stubFetch((path, method) => {
        if (method === 'POST' && path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [wait] });
        }
        if (method === 'GET' && path === '/sdk/v1/scenarios/pending') {
          return jsonResponse({ effects: pending });
        }
        return jsonResponse({});
      });

      await scenarios.send('test');
      expect(onWait).toHaveBeenCalledOnce();
      expect(onNotif).not.toHaveBeenCalled();

      pending = [next];
      await vi.advanceTimersByTimeAsync(5_000);
      expect(onNotif).toHaveBeenCalledOnce();
      expect(onNotif.mock.calls[0][0].message).toBe('after wait');
      const session = onWait.mock.calls[0][0] as WaitEffect;
      expect(session.deadlineUtc.toISOString()).toBe(deadline);
    });
  });

  describe('expired-run drop', () => {
    it('drops the run on unknown_run and does not retry it', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
      const onFailed = vi.fn();
      const onNotif = vi.fn();
      client.effects.onScenarioFailed(onFailed);
      client.effects.onNotification(onNotif);
      const pending = effect('notification', { message: 'hello' });

      stubFetch((path) => {
        if (path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [pending] });
        }
        if (path === '/sdk/v1/scenarios/callback') {
          return jsonResponse({ code: 'unknown_run', error: 'gone' }, 410);
        }
        if (path === '/sdk/v1/scenarios/pending') {
          return jsonResponse({ effects: [pending] });
        }
        return jsonResponse({});
      });

      await scenarios.send('test');
      expect(onNotif).toHaveBeenCalledOnce();
      await expect((onNotif.mock.calls[0][0] as NotificationEffect).done())
        .rejects.toBeInstanceOf(RudderHttpError);
      expect(onFailed).toHaveBeenCalledOnce();
      expect(onFailed.mock.calls[0][0].runId).toBe('run-1');
      expect(scenarios.isRunning).toBe(false);

      await scenarios.start();
      expect(onNotif).toHaveBeenCalledTimes(1);
      warn.mockRestore();
      client.dispose();
    });

    it('leaves the effect active on a transient callback error', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onFailed = vi.fn();
      const onNotif = vi.fn();
      client.effects.onScenarioFailed(onFailed);
      client.effects.onNotification(onNotif);

      stubFetch((path) => {
        if (path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [effect('notification')] });
        }
        if (path === '/sdk/v1/scenarios/callback') {
          return jsonResponse({ error: 'boom' }, 500);
        }
        return jsonResponse({});
      });

      await scenarios.send('test');
      await (onNotif.mock.calls[0][0] as NotificationEffect).done();
      expect(onFailed).not.toHaveBeenCalled();
      expect(scenarios.isRunning).toBe(true);
    });
  });

  describe('store session', () => {
    it('buy() purchases the selected offer and completes with onPurchase', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onStore = vi.fn();
      client.effects.onStoreOffer(onStore);

      stubFetch((path, method) => {
        if (method === 'POST' && path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [effect('store', { storeSlug: 'starter' })] });
        }
        if (method === 'GET' && path === '/sdk/v1/stores/starter') {
          return jsonResponse({
            name: 'Starter',
            slug: 'starter',
            offers: [{ id: 'pack_1', slug: 'pack-1', name: 'Starter Pack' }],
          });
        }
        if (method === 'POST' && path === '/sdk/v1/stores/starter/offers/pack-1/purchase') {
          return jsonResponse({ success: true, purchaseId: 'purchase-1' });
        }
        return jsonResponse({});
      });

      await scenarios.send('test');
      await vi.waitFor(() => expect(onStore).toHaveBeenCalledOnce());
      const session = onStore.mock.calls[0][0] as StoreOfferEffect;
      const purchase = await session.buy(session.offers[0]);
      expect(purchase.success).toBe(true);

      const duplicate = await session.buy(session.offers[0]);
      expect(duplicate.success).toBe(false);
    });

    it('dismiss() completes with onDecline', async () => {
      const { client, scenarios } = await createClientWithScenario();
      const onStore = vi.fn();
      client.effects.onStoreOffer(onStore);
      stubFetch((path) => {
        if (path === '/sdk/v1/scenarios/trigger') {
          return jsonResponse({ effects: [effect('store', { storeSlug: 'starter' })] });
        }
        if (path === '/sdk/v1/stores/starter') {
          return jsonResponse({ slug: 'starter', offers: [{ id: 'pack_1', slug: 'pack-1' }] });
        }
        return jsonResponse({});
      });
      await scenarios.send('test');
      await vi.waitFor(() => expect(onStore).toHaveBeenCalledOnce());
      await (onStore.mock.calls[0][0] as StoreOfferEffect).dismiss();
      const fetchMock = vi.mocked(fetch);
      const callbackCall = fetchMock.mock.calls.find((call) =>
        String(call[0]).includes('/sdk/v1/scenarios/callback'),
      );
      expect(JSON.parse(callbackCall![1]!.body as string).handle).toBe('onDecline');
    });
  });

  describe('clear', () => {
    it('clear removes all runs', async () => {
      const { client, scenarios } = await createClientWithScenario();
      client.effects.onNotification(vi.fn());
      stubFetch(() => jsonResponse({ effects: [effect('notification')] }));
      await scenarios.send('test');
      expect(scenarios.isRunning).toBe(true);
      scenarios.clear();
      expect(scenarios.isRunning).toBe(false);
    });
  });
});