module.exports = {
  id: 'memory_write',
  signature: 'memory_write(slot, text)',
  description: 'Write one of 3 scratchpad slots for short-term reminders.',
  parameters: {
    type: 'object',
    properties: {
      slot: { type: 'integer', minimum: 1, maximum: 3 },
      text: { type: 'string', minLength: 1, maxLength: 180 },
    },
    required: ['slot', 'text'],
    additionalProperties: false,
  },
  availability() {
    return { available: true, reason: null };
  },
  async execute({ args = {}, memoryStore }) {
    const slot = Math.max(1, Math.min(3, Number(args?.slot) || 0));
    if (!slot) throw new Error('memory_write requires args.slot 1..3');
    const text = String(args?.text || '').trim();
    if (!text) throw new Error('memory_write requires args.text');
    const next = memoryStore && typeof memoryStore === 'object' ? { ...memoryStore } : {};
    const slots = Array.isArray(next.slots) ? [...next.slots] : ['', '', ''];
    while (slots.length < 3) slots.push('');
    slots[slot - 1] = text.slice(0, 180);
    next.slots = slots.slice(0, 3);
    return { ok: true, memory: next };
  },
};