package main

import (
	"fmt"
	"log"
	"os/exec"

	p "github.com/mafik/pulseaudio"
)

var SoundVolume = "🔊:0%"
var pa *p.Client

// UpdateVolumeInfo updates info about current Sound Volume.
func UpdateVolumeInfo() {
	var err error

	pa, err = p.NewClient()

	// It can happen if no pulseaudio server running for current user.
	// If no server running we have to run one.
	if err != nil {
		if err := PaReinit(); err != nil {
			log.Print(err)

			return
		}
	}

	vol, err := pa.Volume()

	if err != nil {
		log.Printf("Unable get volume from pulseaudio server: %s", err)

		return
	}

	SoundVolume = fmt.Sprintf("%s:%d%%", Conf.SimpleVolumePa.Symbol, int64(vol*100))

	UpdateReady <- true

	for {
		// Subscribe to update notification channel, to get info that volume changed
		pulseUpdate, err := pa.Updates()

		if err != nil {
			log.Printf("Unable to subscribe to pulseaudio updates: %s", err)

			return
		}

		// Rake update events
		for range pulseUpdate {
			vol, err = pa.Volume()

			if err != nil {
				log.Printf("Unable get volume from pulseaudio server: %s", err)

				return
			}

			SoundVolume = fmt.Sprintf("%s:%d%%", Conf.SimpleVolumePa.Symbol, int64(vol*100))

			UpdateReady <- true
		}

		if err := PaReinit(); err != nil {
			log.Print(err)

			return
		}
	}

	// This code is unreachable :(
	pa.Close()
}

// PaReinit re-inits pulseaudio and connection to it.
func PaReinit() error {
	var err error

	// If we out of updates, it seems that someone killed pulseaudio server. Restart it.
	cmd := exec.Command("pulseaudio", "--check")

	if err := cmd.Run(); err == nil {
		return fmt.Errorf("pulseaudio is already running, but we have troubles contacting it: %w", err)
	}

	cmd = exec.Command("pulseaudio", "--start")

	if err := cmd.Run(); err != nil {
		return fmt.Errorf("unable to initialize pulseaudio server instance: %w", err)
	} //nolint:wsl

	pa, err = p.NewClient()

	if err != nil {
		return fmt.Errorf("unable to make client connection to pulseaudio: %s", err)
	} //nolint:wsl

	return err
}