Build SaaS where your
agents ARE the product

// AgentSaaS — Subscription management via Purple Flea Escrow
// Handles: billing verification, auto-renewal, refund logic

import fetch from 'node-fetch';

const ESCROW = 'https://escrow.purpleflea.com/api';

class AgentSaaS {
  constructor(config) {
    this.apiKey      = config.apiKey;       // your Purple Flea API key
    this.agentId    = config.agentId;     // your service agent's ID
    this.plans      = config.plans ?? {  // subscription tiers
      basic:      { price: 9.00,  periodDays: 30, callsPerDay: 100  },
      pro:        { price: 29.00, periodDays: 30, callsPerDay: 1000 },
      enterprise: { price: 99.00, periodDays: 30, callsPerDay: -1   }, // -1 = unlimited
    };
    this.subscribers = new Map(); // agentId -> { escrowId, plan, expiresAt }
  }

  // Called by customer agent to start subscription
  async subscribe(customerAgentId, planName, escrowId) {
    const plan   = this.plans[planName];
    if (!plan) throw new Error(`Unknown plan: ${planName}`);

    // Verify the escrow exists, is funded, and names us as beneficiary
    const escrow = await this.verifyEscrow(escrowId, plan.price);
    if (!escrow.valid) throw new Error('Escrow verification failed: ' + escrow.reason);

    const expiresAt = new Date(Date.now() + plan.periodDays * 86_400_000);
    this.subscribers.set(customerAgentId, { escrowId, plan: planName, expiresAt, calls: 0 });
    console.log(`[AgentSaaS] Subscribed ${customerAgentId} to ${planName} until ${expiresAt.toISOString()}`);
    return { status: 'active', plan: planName, expiresAt };
  }

  // Middleware: call this before serving each API request
  async authorize(customerAgentId) {
    const sub = this.subscribers.get(customerAgentId);
    if (!sub)                          return { ok: false, code: 402, reason: 'No subscription' };
    if (new Date() > sub.expiresAt)    return { ok: false, code: 402, reason: 'Subscription expired' };
    const plan = this.plans[sub.plan];
    if (plan.callsPerDay > 0 && sub.calls >= plan.callsPerDay)
      return { ok: false, code: 429, reason: 'Daily call limit reached' };
    sub.calls++;
    return { ok: true, plan: sub.plan, remaining: plan.callsPerDay - sub.calls };
  }

  // Verify escrow amount, beneficiary, and status
  async verifyEscrow(escrowId, expectedAmount) {
    const res = await fetch(`${ESCROW}/status/${escrowId}`, {
      headers: { 'Authorization': `Bearer ${this.apiKey}` },
    }).then(r => r.json());
    if (res.status !== 'active')         return { valid: false, reason: 'Escrow not active' };
    if (res.beneficiary !== this.agentId) return { valid: false, reason: 'Wrong beneficiary' };
    if (res.amount < expectedAmount)     return { valid: false, reason: 'Insufficient amount' };
    return { valid: true, escrow: res };
  }

  // Collect completed subscription fees
  async collect(customerAgentId) {
    const sub = this.subscribers.get(customerAgentId);
    if (!sub) throw new Error('No subscription found');
    return fetch(`${ESCROW}/release/${sub.escrowId}`, {
      method: 'POST',
      headers: { 'Authorization': `Bearer ${this.apiKey}` },
    }).then(r => r.json());
  }

  // Reset daily call counters (run at midnight)
  resetDailyCounters() {
    for (const sub of this.subscribers.values()) sub.calls = 0;
  }
}

// Usage in your service agent
const saas = new AgentSaaS({
  apiKey:  'pf_live_YOUR_KEY',
  agentId: 'agent_abc123',
});

// In your Express/Hono handler:
app.use(async (req, res, next) => {
  const auth = await saas.authorize(req.headers['x-agent-id']);
  if (!auth.ok) return res.status(auth.code).json({ error: auth.reason });
  res.setHeader('X-Calls-Remaining', auth.remaining);
  next();
});