import { describe, expect, it } from 'vitest';
import { findPrimaryProjectAgentSession } from '@/lib/project-agent-session';

describe('project Agent primary session selection', () => {
  it('prefers an older active session over a newer empty duplicate', () => {
    const empty = {
      id: 'ses_empty',
      agent: 'game-design',
      time: { created: 200, updated: 200 },
      tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
      cost: 0,
    };
    const historical = {
      id: 'ses_history',
      agent: 'game-design',
      time: { created: 100, updated: 150 },
      tokens: { input: 10, output: 20, reasoning: 0, cache: { read: 0, write: 0 } },
      cost: 0.1,
    };

    expect(findPrimaryProjectAgentSession([empty, historical], 'game-design')).toBe(historical);
  });

  it('keeps runtime order when multiple matching sessions are active', () => {
    const newest = { id: 'ses_newest', agent: 'game-design', time: { created: 100, updated: 300 } };
    const older = { id: 'ses_older', agent: 'game-design', time: { created: 100, updated: 200 } };

    expect(findPrimaryProjectAgentSession([newest, older], 'game-design')).toBe(newest);
  });

  it('reuses the first empty match instead of requesting another duplicate', () => {
    const first = { id: 'ses_first', agent: 'game-art', time: { created: 200, updated: 200 } };
    const second = { id: 'ses_second', agent: 'game-art', time: { created: 100, updated: 100 } };

    expect(findPrimaryProjectAgentSession([first, second], 'game-art')).toBe(first);
  });

  it('ignores sessions owned by other Agents', () => {
    expect(findPrimaryProjectAgentSession([
      { id: 'ses_other', agent: 'game-development', time: { created: 100, updated: 200 } },
    ], 'game-design')).toBeUndefined();
  });

  it('recognizes legacy string timestamps and token activity', () => {
    const legacy = {
      id: 'ses_legacy',
      agent: 'game-design',
      createdAt: '2026-07-13T00:00:00.000Z',
      updatedAt: '2026-07-13T00:01:00.000Z',
    };
    const tokenOnly = {
      id: 'ses_token',
      agent: 'game-art',
      tokens: { input: 1, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
    };

    expect(findPrimaryProjectAgentSession([legacy], 'game-design')).toBe(legacy);
    expect(findPrimaryProjectAgentSession([tokenOnly], 'game-art')).toBe(tokenOnly);
  });

  it('does not treat an all-zero summary as conversation activity', () => {
    const emptySummary = {
      id: 'ses_empty_summary',
      agent: 'game-design',
      summary: { additions: 0, deletions: 0, files: 0, diffs: [] },
    };
    const historical = {
      id: 'ses_historical_summary',
      agent: 'game-design',
      summary: { additions: 1, deletions: 0, files: 1, diffs: [] },
    };

    expect(findPrimaryProjectAgentSession([emptySummary, historical], 'game-design')).toBe(historical);
  });
});