package sfive

import (
	"bytes"
	"encoding/json"
	"net/http"
	"time"
)

func findMaxId(values []dataUpdateDb) int {
	maxId := -1
	for i := range values {
		if values[i].Id > maxId {
			maxId = values[i].Id
		}
	}
	return maxId
}

func (self StatsSinkServer) handleForwarding(url string, client *http.Client) {
	latestId := 0 // TODO retrieve latest known from server
next:
	// TODO forwarding
	for {
		time.Sleep(500)

		updates, err := self.store.GetUpdatesAfter(latestId)
		if err != nil {
			s5l.Printf("fwd: failed reading updates: %v\n", err)
			continue next
		}

		for i := range updates {
			data, err := json.Marshal(updates[i])
			if err == nil {
				s5l.Printf("fwd: encode failed: %v\n", err)
				// TODO retry etc.
				continue
			}

			_, err = client.Post(url, "application/json", bytes.NewBuffer(data))
			if err == nil {
				latestId = findMaxId(updates)
			} else {
				s5l.Printf("fwd: post failed: %v\n", err)
				// TODO retry etc.
			}
		}
	}
}

func (self StatsSinkServer) RunForwarding(forwardBaseUrl string) {
	forwardUrl := forwardBaseUrl + "/updates"
	self.handleForwarding(forwardUrl, http.DefaultClient)
}