package scaler

import (
	"fmt"
	"time"

	"git.stinnesbeck.com/go/jynx/backend/common"
	"git.stinnesbeck.com/go/jynx/backend/hetzner"
	"git.stinnesbeck.com/go/jynx/ci/woodpecker"
	"git.stinnesbeck.com/go/jynx/db"
	"git.stinnesbeck.com/go/log"
)

func Start(w *woodpecker.Server) error {
	log.PrintDebug("Starting autoscaler")
	stats, err := w.GetStats()
	if err != nil {
		return err
	}

	// read info from database
	servers, err := db.Read()
	if err != nil {
		return err
	}

	var newServers int

	if stats.PendingJobs == 0 || stats.IdlingWorkers+stats.RunningJobs+uint(len(servers)) >= stats.PendingJobs {
		return nil
	}

	log.PrintInfo("starting", stats.PendingJobs, "workers")

	newServers += int(stats.PendingJobs)
	var ScaleUpServers []common.Server

	for i := 0; i < newServers; i++ {
		name := fmt.Sprintf("jynx-worker-%d", i+1)

		ScaleUpServers = append(ScaleUpServers, common.Server{
			Name:    name,
			Created: time.Now(),
		})
		if err := hetzner.AddServer(ScaleUpServers[i]); err != nil {
			return err
		}
	}

	// save servers to database
	servers = append(servers, ScaleUpServers...)
	if err := db.Save(servers); err != nil {
		return err
	}

	log.PrintInfo(stats.RunningJobs, "running jobs,", stats.PendingJobs, "pending jobs,", stats.IdlingWorkers, "idling workers,", len(servers), "servers starting up")

	return nil
}