import { ErrorCode } from '@lingxi/shared';
import { describe, expect, it, vi } from 'vitest';

import { AppException } from '../../common/errors/app-exception';
import type { SystemConfigService } from '../platform/system-config/system-config.service';
import { estimateTask, MediaTaskEstimator } from './media-task-estimator';

function expectCode(fn: () => unknown, code: ErrorCode): void {
  try {
    fn();
  } catch (error) {
    expect(error).toBeInstanceOf(AppException);
    expect((error as AppException).code).toBe(code);
    return;
  }
  throw new Error('预期抛出 AppException');
}

const CONFIG = { maxItems: 20, costPerItem: 0.02, secondsPerItem: 3 };

describe('任务预估纯计算（R-26：上限 / 单价来自系统配置）', () => {
  it('返回条数 / 成本（2 位小数）/ 耗时', () => {
    expect(estimateTask('demo', 5, CONFIG)).toEqual({
      estimatedItems: 5,
      estimatedCost: 0.1,
      estimatedSeconds: 15,
    });
    // 0.02 * 3 = 0.06 不产生浮点尾巴
    expect(estimateTask('demo', 3, CONFIG).estimatedCost).toBe(0.06);
    expect(estimateTask('demo', 20, CONFIG).estimatedCost).toBe(0.4);
  });

  it('项数超过配置上限 → 40001（业务上限，不是 schema 硬上限）', () => {
    expectCode(() => estimateTask('demo', 21, CONFIG), ErrorCode.PARAM_INVALID);
    expectCode(
      () => estimateTask('demo', 101, { ...CONFIG, maxItems: 100 }),
      ErrorCode.PARAM_INVALID,
    );
  });

  it('非法项数 / 非法配置 → 40001', () => {
    expectCode(() => estimateTask('demo', 0, CONFIG), ErrorCode.PARAM_INVALID);
    expectCode(() => estimateTask('demo', 2.5, CONFIG), ErrorCode.PARAM_INVALID);
    expectCode(() => estimateTask('demo', 1, { ...CONFIG, maxItems: 0 }), ErrorCode.PARAM_INVALID);
    expectCode(
      () => estimateTask('demo', 1, { ...CONFIG, costPerItem: Number.NaN }),
      ErrorCode.PARAM_INVALID,
    );
    expectCode(
      () => estimateTask('demo', 1, { ...CONFIG, costPerItem: -1 }),
      ErrorCode.PARAM_INVALID,
    );
    expectCode(
      () => estimateTask('demo', 1, { ...CONFIG, secondsPerItem: 0 }),
      ErrorCode.PARAM_INVALID,
    );
    expectCode(
      () => estimateTask('demo', 1, { ...CONFIG, secondsPerItem: Number.POSITIVE_INFINITY }),
      ErrorCode.PARAM_INVALID,
    );
  });
});

describe('MediaTaskEstimator（读 SystemConfigService）', () => {
  function estimatorWith(values: readonly number[]): {
    estimator: MediaTaskEstimator;
    getNumber: ReturnType<typeof vi.fn>;
  } {
    const getNumber = vi.fn();
    for (const value of values) getNumber.mockResolvedValueOnce(value);
    const config = { getNumber } as unknown as SystemConfigService;
    return { estimator: new MediaTaskEstimator(config), getNumber };
  }

  it('按配置计算预估', async () => {
    const { estimator, getNumber } = estimatorWith([20, 0.02, 3]);
    await expect(estimator.estimate('demo', 5)).resolves.toEqual({
      estimatedItems: 5,
      estimatedCost: 0.1,
      estimatedSeconds: 15,
    });
    expect(getNumber).toHaveBeenNthCalledWith(1, 'task.demo.max_items');
    expect(getNumber).toHaveBeenNthCalledWith(2, 'task.estimate.demo_cost_per_item');
    expect(getNumber).toHaveBeenNthCalledWith(3, 'task.estimate.demo_seconds_per_item');
  });

  it('读配置失败（缺预估字段）→ 40001，不允许静默 0', async () => {
    const getNumber = vi.fn().mockRejectedValue(new Error('system_configs 不可用'));
    const config = { getNumber } as unknown as SystemConfigService;
    const estimator = new MediaTaskEstimator(config);
    await expect(estimator.estimate('demo', 5)).rejects.toMatchObject({
      code: ErrorCode.PARAM_INVALID,
    });
  });

  it('配置值越界（超过上限）→ 40001', async () => {
    const { estimator } = estimatorWith([4, 0.02, 3]);
    await expect(estimator.estimate('demo', 5)).rejects.toMatchObject({
      code: ErrorCode.PARAM_INVALID,
    });
  });
});