/**
 * TodoWrite tool — visible task planning (audit D5-5).
 *
 * The tool itself is a no-op acknowledgement: its value is the bot:tool event
 * the session already emits for every tool_use — on the dashboard that commits
 * the streamed text as its own bubble (the plan "rhythm" claude users see),
 * and on WhatsApp/Telegram it flushes the pending chunk as an intermediate
 * progress message. Claude's TodoWrite works the same way from the harness's
 * point of view. Deliberately NOT in FILE_TOOL_NAMES — updating a plan must
 * never trigger a backend restart.
 */
import type { PiTool } from './types.js';

export const todoWriteTool: PiTool = {
  name: 'TodoWrite',
  description:
    'Maintain a visible todo list for multi-step tasks. Call it when you start a task (all items pending, ' +
    'first in_progress) and again after each step completes. Exactly one item should be in_progress at a time.',
  inputSchema: {
    type: 'object',
    properties: {
      todos: {
        type: 'array',
        description: 'The complete, updated todo list (replaces the previous one).',
        items: {
          type: 'object',
          properties: {
            content: { type: 'string', description: 'Imperative description, e.g. "Add the API route".' },
            status: { type: 'string', enum: ['pending', 'in_progress', 'completed'] },
            activeForm: { type: 'string', description: 'Present-continuous label shown while in_progress.' },
          },
          required: ['content', 'status'],
        },
      },
    },
    required: ['todos'],
  },

  async run(input) {
    const todos = Array.isArray(input?.todos) ? input.todos : [];
    if (todos.length === 0) return { output: 'Todo list cleared.' };
    const done = todos.filter((t: any) => t?.status === 'completed').length;
    return { output: `Todo list updated (${done}/${todos.length} completed).` };
  },
};