import { test } from 'node:test';
import assert from 'node:assert/strict';
import {
  truncateDiff,
  fallbackSummary,
  buildResolveBranchName,
  buildResolveBody,
} from './index.js';

test('truncateDiff: 內容在上限內不截斷', () => {
  const { diff, truncated } = truncateDiff('abc', 100);
  assert.equal(diff, 'abc');
  assert.equal(truncated, false);
});

test('truncateDiff: null/空字串回傳空字串且不截斷', () => {
  assert.deepEqual(truncateDiff(null, 100), { diff: '', truncated: false });
  assert.deepEqual(truncateDiff('', 100), { diff: '', truncated: false });
});

test('truncateDiff: 超過上限時截斷並標示', () => {
  const big = 'x'.repeat(50);
  const { diff, truncated } = truncateDiff(big, 10);
  assert.equal(truncated, true);
  assert.ok(diff.startsWith('xxxxxxxxxx'));
  assert.ok(diff.includes('已截斷'));
});

test('fallbackSummary: 取首個 commit 當標題', () => {
  const s = fallbackSummary({
    source: 'feature',
    target: 'develop',
    commitMessages: '- feat: 新增功能\n- fix: 修正',
    diffStat: ' a.js | 2 +-',
  });
  assert.equal(s.title, 'feat: 新增功能');
  assert.ok(s.description.includes('## 變更摘要'));
  assert.ok(s.description.includes('a.js'));
});

test('fallbackSummary: 無 commit 時退回 Merge 標題且描述非空', () => {
  const s = fallbackSummary({
    source: 'feature',
    target: 'develop',
    commitMessages: '',
    diffStat: '',
  });
  assert.equal(s.title, 'Merge feature into develop');
  assert.ok(s.description.includes('(無)'));
  assert.ok(s.description.length > 0);
});

test('buildResolveBranchName: 含前綴並淨化非法字元', () => {
  const name = buildResolveBranchName('develop', 'feature/x y');
  assert.ok(name.startsWith('resolve-conflict/'));
  assert.ok(name.includes('-into-'));
  // 空白等非法字元被替換為 -
  assert.ok(!/\s/.test(name));
});

test('buildResolveBranchName: 過長 target/source 仍遠低於 255', () => {
  const long = 'a'.repeat(500);
  const name = buildResolveBranchName(long, long);
  assert.ok(name.length < 255);
});

test('buildResolveBody: 含衝突檔案清單與人工檢查清單', () => {
  const body = buildResolveBody({
    source: 'feature',
    target: 'develop',
    resolveBranch: 'resolve-conflict/develop-into-feature',
    files: ['a.js', 'b.js'],
    summary: { title: 't', description: '摘要內容' },
  });
  assert.ok(body.includes('- `a.js`'));
  assert.ok(body.includes('- `b.js`'));
  assert.ok(body.includes('合併前人工檢查清單'));
  assert.ok(body.includes('摘要內容'));
});