import { readHostLocale, translate, type Locale } from './i18n.js';
import type { Context } from '@deepseek-ai/cordis';
import type { Agent } from '@deepseek-ai/dsh-agent';
import type { AskUserQuestionItem } from '@deepseek-ai/dsh-user-questions';
import { git, parseTarget, type Target } from './request.js';

/** 复用宿主的问题服务；选择过程属于主 Agent，审查子 Agent 不向用户提问。 */
export async function selectTarget(ctx: Context, agent: Agent, input: string, signal: AbortSignal, locale: Locale = readHostLocale(ctx)): Promise<Target> {
  const t = (key: Parameters<typeof translate>[1]) => translate(locale, key);
  if (input.trim()) return parseTarget(input);
  const ask = async (question: AskUserQuestionItem) => {
    signal.throwIfAborted();
    const result = await ctx.userQuestions.ask({ agent, signal, questions: [question] });
    signal.throwIfAborted();
    const answer = result.answers.find(item => item.id === question.id);
    if (!answer || answer.selected.length > 1) throw new Error(t('未选择有效审查范围。'));
    const value = answer.custom?.trim() || answer.selected[0];
    if (!value) throw new Error(t('审查选择已取消或未填写。'));
    return value;
  };
  const choice = await ask({ id: 'review-scope', header: t('代码审查'), question: t('选择审查范围'), options: [
    { label: t('对比基准分支'), description: t('从共同祖先审查当前分支的更改') },
    { label: t('审查未提交的更改'), description: t('审查暂存、未暂存及未跟踪的净更改') },
    { label: t('审查某次提交'), description: t('选择一个 Git 提交') },
    { label: t('自定义审查要求'), description: t('输入本次需要检查的内容') },
  ] });
  if (choice === t('审查未提交的更改')) return { mode: 'worktree' };
  if (choice === t('自定义审查要求')) return parseTarget(await ask({ id: 'review-instructions', question: t('请输入自定义审查要求') }));
  if (![t('对比基准分支'), t('审查某次提交')].includes(choice)) return parseTarget(choice);
  const cwd = agent.session.header.cwd;
  if (!cwd) throw new Error(t('当前会话没有工作目录。'));
  if (choice === t('对比基准分支')) {
    const branches = (await git(cwd, ['for-each-ref', '--format=%(refname:short)', 'refs/heads'], signal)).toString('utf8').trim().split('\n').filter(Boolean);
    const ref = await ask({ id: 'review-base', question: t('选择基准分支，也可输入其他分支或引用'), options: branches.map(label => ({ label })) });
    return { mode: 'base', ref };
  }
  const commits = (await git(cwd, ['log', '-n', '100', '--format=%H%x09%s'], signal)).toString('utf8').trim().split('\n').filter(Boolean);
  const options = commits.map(line => { const [sha, ...subject] = line.split('\t'); return { label: `${sha!.slice(0, 10)} ${subject.join('\t')}`, sha: sha! }; });
  const selected = await ask({ id: 'review-commit', question: t('选择提交，也可输入其他提交 SHA 或引用'), options: options.map(({ label }) => ({ label })) });
  const commit = options.find(item => item.label === selected);
  return { mode: 'commit', ref: commit?.sha ?? selected, ...(commit ? { title: commit.label.slice(11) } : {}) };
}