package util

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"time"
)

const RedrawInterval = 250 * time.Millisecond

func Periodic(ctx context.Context, interval time.Duration, fn func() error) {
	if err := fn(); err != nil {
		panic(err)
	}
	ticker := time.NewTicker(interval)
	defer ticker.Stop()
	for {
		select {
		case <-ticker.C:
			if err := fn(); err != nil {
				panic(err)
			}
		case <-ctx.Done():
			return
		}
	}
}

func PanicOnErrorWithResult[E any](result E, err error) E {
	if err != nil {
		panic(err)
	}
	return result
}

func PanicOnError(err error) {
	if err != nil {
		panic(err)
	}
}

func DecodeJSON(r io.Reader, v any) error {
	dec := json.NewDecoder(r)
	if err := dec.Decode(v); err != nil {
		if err == io.EOF {
			return fmt.Errorf("empty stats stream")
		}
		return err
	}
	return nil
}