package background

import (
	"fmt"
	"runtime"
	"time"

	"git.fjla.uk/owlboard/timetable-mgr/cif"
	"git.fjla.uk/owlboard/timetable-mgr/corpus"
	"git.fjla.uk/owlboard/timetable-mgr/helpers"
	"git.fjla.uk/owlboard/timetable-mgr/log"
)

const frequency = 2 * time.Hour // Figure out a sensible frequency!

// Starts a background ticker to run background tasks.  Uses the frequency configured in the background/ticker.go file
func InitTicker(cfg *helpers.Configuration, stop <-chan struct{}) {
	go runTicker(cfg, stop)

	// Run goroutine logging ticker if runtime set to debug
	if helpers.Runtime == "debug" {
		go goroutineTicker(stop)
	}
}

// Runs the ticker and handles tick events
func runTicker(cfg *helpers.Configuration, stop <-chan struct{}) {
	log.Msg.Sugar().Infof("Starting background ticker, runs every %s", frequency)
	ticker := time.NewTicker(frequency)
	defer ticker.Stop()

	for {
		select {
		case <-stop:
			return
		case <-ticker.C:
			go cif.CheckCif(cfg)
			go corpus.CheckCorpus(cfg)
		}
	}
}

// Starts a ticker that logs how many goroutines are running every two seconds
func goroutineTicker(stop <-chan struct{}) {
	log.Msg.Warn("Starting goroutine Tracker ticker - DEBUG USE ONLY")
	ticker := time.NewTicker(1000 * time.Millisecond)
	defer ticker.Stop()
	for {
		select {
		case <-stop:
			return
		case <-ticker.C:
			debugLog()
		}
	}
}

func debugLog() {
	var memStats runtime.MemStats
	runtime.ReadMemStats(&memStats)

	goroutines := runtime.NumGoroutine()

	fmt.Printf("\nNumber of goroutines: %d\n", goroutines)
	fmt.Printf("Heap Allocated memory: %2f MB\n\n", float64(memStats.HeapAlloc)/(1024*1024))
}