// Webhook receiver for external integrations
// Path: /webhook

const handler = async (request) => {
  if (request.method === 'OPTIONS') {
    let response = new Response('')
    response.headers.set('Access-Control-Allow-Origin', '*')
    response.headers.set('Access-Control-Allow-Methods', 'GET, POST, OPTIONS')
    response.headers.set('Access-Control-Allow-Headers', 'Content-Type, Authorization, X-Webhook-Secret')
    return response
  }

  // GET request - return webhook info
  if (request.method === 'GET') {
    let response = new Response(JSON.stringify({
      endpoint: '/webhook',
      method: 'POST',
      supported_sources: ['gitea', 'stripe', 'supabase', 'default'],
      usage: 'POST /webhook?source=gitea with JSON body'
    }, null, 2))
    response.headers.set('Content-Type', 'application/json')
    response.headers.set('Access-Control-Allow-Origin', '*')
    return response
  }

  // POST request - receive and forward webhook
  if (request.method === 'POST') {
    try {
      const timestamp = new Date().toISOString()

      // Parse request body
      let payload
      const contentType = request.headers.get('content-type') || ''

      if (contentType.indexOf('application/json') !== -1) {
        payload = await request.json()
      } else {
        payload = await request.text()
      }

      // Get source from query params
      let source = 'default'
      const reqUrl = request.url || ''
      if (reqUrl.indexOf('?') !== -1) {
        const queryString = reqUrl.split('?')[1]
        if (queryString) {
          const params = queryString.split('&')
          for (let i = 0; i < params.length; i++) {
            const pair = params[i].split('=')
            if (pair[0] === 'source' && pair[1]) {
              source = decodeURIComponent(pair[1])
              break
            }
          }
        }
      }

      // Forward to appropriate n8n workflow based on source
      const webhookMap = {
        'gitea': 'https://n8n.mylder.io/webhook/gitea-event',
        'stripe': 'https://n8n.mylder.io/webhook/stripe-event',
        'supabase': 'https://n8n.mylder.io/webhook/supabase-event',
        'default': 'https://n8n.mylder.io/webhook/generic-event'
      }

      const targetUrl = webhookMap[source] || webhookMap['default']

      // Forward to n8n (fire and forget)
      fetch(targetUrl, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          source: source,
          payload: payload,
          received_at: timestamp
        })
      })

      let response = new Response(JSON.stringify({
        received: true,
        source: source,
        timestamp: timestamp
      }))
      response.headers.set('Content-Type', 'application/json')
      response.headers.set('Access-Control-Allow-Origin', '*')
      return response

    } catch (error) {
      let response = new Response(JSON.stringify({
        received: false,
        error: error.message || 'Parse error'
      }))
      response.headers.set('Content-Type', 'application/json')
      response.headers.set('Access-Control-Allow-Origin', '*')
      return response
    }
  }

  // Method not allowed
  let response = new Response(JSON.stringify({ error: 'Method not allowed' }))
  response.headers.set('Content-Type', 'application/json')
  response.headers.set('Access-Control-Allow-Origin', '*')
  return response
}

addEventListener('fetch', event => {
  return event.respondWith(handler(event.request))
})