banner_studio/packages/api-lib/test/generate-agent.test.ts

import { describe, expect, it, vi } from 'vitest';
import type { GenerateOutputV2 } from '@banner-studio/types';
import type { PerSizeConstraints } from '@banner-studio/prompts';
import { generateAgent, computeOverflows } from '../src/ai-orchestration/generate-agent.js';

const constraints: PerSizeConstraints = {
  '300x600': { headline: 60, subheadline: 110, cta_text: 18, legal: 80 },
  '300x250': { headline: 35, subheadline: 60, cta_text: 14 },
  '728x90':  { headline: 36, subheadline: 70, cta_text: 14 },
  '160x600': { headline: 28, subheadline: 70, cta_text: 14, legal: 60 }
};

const ctx = {
  subject: 'velvet sofa',
  audience_hint: 'design-aware buyers',
  tone_hint: 'premium, calm',
  key_benefits: ['handmade', 'lifetime frame'],
  cta_intent: 'shop now'
};

const fittingOutput: GenerateOutputV2 = {
  per_size: {
    '300x600': {
      headline: 'Velvet sofas, made to last decades',
      subheadline: 'Handmade frames, decade-long warranty, free white-glove delivery.',
      cta_text: 'Shop velvet sofas',
      legal: 'Terms apply.'
    },
    '300x250': {
      headline: 'Velvet sofas built to last',
      subheadline: 'Handmade frames, decade warranty.',
      cta_text: 'Shop now'
    },
    '728x90': {
      headline: 'Velvet sofas, made to last',
      subheadline: 'Handmade frames, decade-long warranty.',
      cta_text: 'Shop now'
    },
    '160x600': {
      headline: 'Velvet sofas',
      subheadline: 'Handmade frames, decade warranty.',
      cta_text: 'Shop now',
      legal: 'Terms apply.'
    }
  },
  rationale: {
    copy: 'tight benefit-led wording',
    asset: 'velvet sofa hero',
    variant: 'standard',
    animation: 'fade cascade'
  }
};

const tooLongOutput: GenerateOutputV2 = {
  per_size: {
    '300x600': {
      headline: 'A headline that is much much much too long to fit any reasonable banner budget here',
      subheadline: 'sub',
      cta_text: 'Shop',
      legal: 'OK'
    },
    '300x250': {
      headline: 'Another headline that is way too long to fit in the rectangle budget',
      subheadline: 'sub',
      cta_text: 'Shop'
    },
    '728x90': {
      headline: 'Yet another headline that is too long for the leaderboard budget here',
      subheadline: 'sub',
      cta_text: 'Shop'
    },
    '160x600': {
      headline: 'A skyscraper headline that overflows the budget',
      subheadline: 'sub',
      cta_text: 'Shop',
      legal: 'OK'
    }
  },
  rationale: { copy: '', asset: '', variant: '', animation: '' }
};

describe('generateAgent', () => {
  it('retries once when the first attempt overflows and succeeds the second time', async () => {
    const call = vi
      .fn()
      .mockResolvedValueOnce(tooLongOutput)
      .mockResolvedValueOnce(fittingOutput);

    const res = await generateAgent({
      context: ctx,
      constraints,
      callClaude: call as unknown as Parameters<typeof generateAgent>[0]['callClaude'],
      maxAttempts: 2
    });

    expect(call).toHaveBeenCalledTimes(2);
    expect(res.status).toBe('ok');
    if (res.status === 'ok') {
      expect(res.output.per_size['300x600']!.headline).toBe('Velvet sofas, made to last decades');
      expect(res.attempts).toBe(2);
    }
  });

  it('returns too_long after maxAttempts without fit', async () => {
    const call = vi.fn().mockResolvedValue(tooLongOutput);
    const res = await generateAgent({
      context: ctx,
      constraints,
      callClaude: call as unknown as Parameters<typeof generateAgent>[0]['callClaude'],
      maxAttempts: 2
    });

    expect(call).toHaveBeenCalledTimes(2);
    expect(res.status).toBe('too_long');
    if (res.status === 'too_long') {
      const headlineOverflows = res.overflows.filter((o) => o.field === 'headline');
      expect(headlineOverflows.length).toBeGreaterThan(0);
      // At least one overflow should carry an artboard_id.
      expect(headlineOverflows[0]!.artboard_id).toMatch(/\d+x\d+/);
    }
  });

  it('succeeds on the first attempt and does not retry', async () => {
    const call = vi.fn().mockResolvedValueOnce(fittingOutput);
    const res = await generateAgent({
      context: ctx,
      constraints,
      callClaude: call as unknown as Parameters<typeof generateAgent>[0]['callClaude'],
      maxAttempts: 2
    });
    expect(call).toHaveBeenCalledTimes(1);
    expect(res.status).toBe('ok');
  });
});

describe('computeOverflows', () => {
  it('reports per-size, per-field overflows independently', () => {
    const partial: GenerateOutputV2 = {
      per_size: {
        '300x250': {
          headline: 'a'.repeat(40), // limit 35 — over by 5
          subheadline: 'b'.repeat(40), // limit 60 — fits
          cta_text: 'c'.repeat(20) // limit 14 — over by 6
        }
      },
      rationale: { copy: '', asset: '', variant: '', animation: '' }
    };
    const overflows = computeOverflows(partial, constraints);
    expect(overflows).toHaveLength(2);
    const headlineOver = overflows.find((o) => o.field === 'headline')!;
    expect(headlineOver.artboard_id).toBe('300x250');
    expect(headlineOver.actual).toBe(40);
    expect(headlineOver.limit).toBe(35);
    const ctaOver = overflows.find((o) => o.field === 'cta_text')!;
    expect(ctaOver.actual).toBe(20);
    expect(ctaOver.limit).toBe(14);
  });

  it('skips fields that are not present in either copy or constraints', () => {
    const partial: GenerateOutputV2 = {
      per_size: {
        '300x250': { headline: 'short', cta_text: 'Shop' } // no subheadline, no legal
      },
      rationale: { copy: '', asset: '', variant: '', animation: '' }
    };
    expect(computeOverflows(partial, constraints)).toEqual([]);
  });

  it('ignores sizes the agent returned that were not asked for', () => {
    const partial: GenerateOutputV2 = {
      per_size: {
        'unknown-size': { headline: 'a'.repeat(999), cta_text: 'a'.repeat(999) }
      },
      rationale: { copy: '', asset: '', variant: '', animation: '' }
    };
    expect(computeOverflows(partial, constraints)).toEqual([]);
  });
});