package main

import (
	"time"

	"pihole-blocklist/bind/internal/httpclient"
)

func getListData() []string {
	var badDomains []string
	listSimple := make(chan []string)
	listComplex := make(chan []string)

	cfg.Log.Info("downloading blocklists")
	// Get Simple Blocklists
	go func() {
		data := getData(cfg.ConfigFile.Sources.DomainListURLs)
		domains := parseSimple(data)
		listSimple <- domains
	}()

	// Get Host File Blocklists
	go func() {
		data := getData(cfg.ConfigFile.Sources.HostFileURLs)
		domains := parseComplex(data)
		listComplex <- domains
	}()

	// Wait for all downloads to finish
	var (
		simple, complex                 []string
		simpleFinished, complexFinished bool
	)

	for {
		select {
		case simple = <-listSimple:
			simpleFinished = true
			cfg.Log.Info("all simple lists downloaded")
		case complex = <-listComplex:
			cfg.Log.Info("all complex lists downloaded")
			complexFinished = true
		default:
			time.Sleep(time.Millisecond * 100)
		}

		if simpleFinished && complexFinished {
			badDomains = append(badDomains, simple...)
			badDomains = append(badDomains, complex...)
			cfg.Log.Info("domains retrieved", "hosts", len(badDomains))
			break
		}
	}

	// append deny list items to list of blocked domains
	badDomains = append(badDomains, cfg.ConfigFile.DenyList...)

	return badDomains
}

func getData(urls []string) []byte {
	listData := make([]byte, 0, len(urls)+1)

	for _, u := range urls {
		cfg.Log.Debug("downloading", "url", u)
		c := httpclient.DefaultClient()
		data, err := c.Get(u)
		if err != nil {
			cfg.Log.Error("unable to get remote content", "error", err, "url", err)
		}
		listData = append(listData, data...)
		// add newline to the end of data, you know, for funzies
		listData = append(listData, '\n')
	}

	return listData
}