import path from 'path';
import fs from 'fs';
import { PROJECT_ROOT, loadJSON } from './shared';
import type { ToolDefinition } from './types';

export const updateManifestItems: ToolDefinition = {
  name: 'update_manifest_items',
  description: '更新 manifest.json 中指定 items 的字段（如 imagePrompt、videoPrompt）。只更新提供的字段，不覆盖其他字段。',
  input_schema: {
    type: 'object',
    properties: {
      manifestPath: { type: 'string', description: 'manifest.json 路径' },
      updates: { type: 'string', description: 'JSON 数组，每个元素需包含 id（shot 序号）和要更新的字段，如 [{id:1,imagePrompt:"..."},{id:2,imagePrompt:"..."}]' },
    },
    required: ['manifestPath', 'updates'],
  },
  execute: async (params) => {
    const { manifestPath, updates } = params as { manifestPath: string; updates: string };
    const resolved = path.isAbsolute(manifestPath)
      ? manifestPath
      : path.resolve(PROJECT_ROOT, manifestPath);

    if (!fs.existsSync(resolved)) return `manifest 不存在: ${resolved}`;

    let updateList: any[];
    try { updateList = JSON.parse(updates); } catch { return '错误: updates 不是合法 JSON'; }
    if (!Array.isArray(updateList)) return '错误: updates 必须是数组';

    const manifest = loadJSON(resolved) as { items: any[] };
    if (!manifest.items) return '错误: manifest 无 items 数组';

    let updated = 0;
    for (const upd of updateList) {
      const idx = manifest.items.findIndex((item: any) => item.id === upd.id);
      if (idx === -1) return `错误: 找不到 id=${upd.id} 的 item`;

      const { id, ...fields } = upd;
      Object.assign(manifest.items[idx], fields);
      updated++;
    }

    fs.writeFileSync(resolved, JSON.stringify(manifest, null, 2), 'utf-8');
    return `已更新 ${updated}/${manifest.items.length} 个 item`;
  },
};