// Follow this setup guide to integrate the Deno language server with your editor:
// https://deno.land/manual/getting_started/setup_your_environment
// This enables autocomplete, go to definition, etc.

import { Redis } from 'https://deno.land/x/upstash_redis@v1.19.3/mod.ts'

console.log(`Function "upstash-redis-counter" up and running!`)

Deno.serve(async (_req) => {
  try {
    const redis = new Redis({
      url: Deno.env.get('UPSTASH_REDIS_REST_URL')!,
      token: Deno.env.get('UPSTASH_REDIS_REST_TOKEN')!,
    })

    const deno_region = Deno.env.get('DENO_REGION')
    if (deno_region) {
      // Increment region counter
      await redis.hincrby('supa-edge-counter', deno_region, 1)
    } else {
      // Increment localhost counter
      await redis.hincrby('supa-edge-counter', 'localhost', 1)
    }

    // Get all values
    const counterHash: Record<string, number> | null = await redis.hgetall('supa-edge-counter')
    const counters = Object.entries(counterHash!)
      .sort(([, a], [, b]) => b - a) // sort desc
      .reduce(
        (r, [k, v]) => ({
          total: r.total + v,
          regions: { ...r.regions, [k]: v },
        }),
        {
          total: 0,
          regions: {},
        }
      )

    return new Response(JSON.stringify({ counters }), { status: 200 })
  } catch (error) {
    return new Response(JSON.stringify({ error: error.message }), {
      status: 200,
    })
  }
})

// To invoke, navigate to 'http://localhost:54321/functions/v1/upstash-redis-counter'.