package hypr

import (
	"errors"
	"fmt"
	"io"
	"io/fs"
	"os"
	"strconv"
	"strings"

	"git.milar.in/milarin/slices"
)

func GetInstance(signature string) (*Instance, error) {
	lockFilePath := fmt.Sprintf("/tmp/hypr/%s.lock", signature)

	file, err := os.Open(lockFilePath)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	data, err := io.ReadAll(file)
	if err != nil {
		return nil, err
	}

	lines := strings.Split(string(data), "\n")

	pid, err := strconv.Atoi(lines[0])
	if err != nil {
		return nil, err
	}

	return &Instance{
		Signature:     signature,
		PID:           pid,
		WaylandSocket: lines[1],
	}, nil
}

func GetDefaultInstance() (*Instance, error) {
	signature, ok := os.LookupEnv("HYPRLAND_INSTANCE_SIGNATURE")
	if !ok {
		return nil, errors.New("default instance not found because HYPRLAND_INSTANCE_SIGNATURE is not set")
	}

	return GetInstance(signature)
}

func GetInstances() ([]*Instance, error) {
	entries, err := os.ReadDir("/tmp/hypr")
	if err != nil {
		return nil, err
	}

	entries = slices.Filter(entries, fs.DirEntry.IsDir)
	instances := make([]*Instance, 0, len(entries))
	for _, entry := range entries {
		instance, err := GetInstance(entry.Name())
		if err != nil {
			fmt.Println(err)
			continue
		}
		instances = append(instances, instance)
	}

	return instances, nil
}