package aoiprxkit

import (
	"context"
	"fmt"
	"io"
)

type SRTConfig struct {
	URL          string
	Mode         string
	SampleRateHz int
	Channels     int
	SourceLabel  string
}

func DefaultSRTConfig() SRTConfig {
	return SRTConfig{
		SampleRateHz: 48000,
		Channels:     2,
		Mode:         "listener",
	}
}

func (c SRTConfig) Validate() error {
	if c.URL == "" {
		return fmt.Errorf("SRT URL must not be empty")
	}
	if c.SampleRateHz <= 0 {
		return fmt.Errorf("SampleRateHz must be > 0")
	}
	if c.Channels < 1 || c.Channels > 2 {
		return fmt.Errorf("Channels must be 1 or 2")
	}
	return nil
}

type SRTConnOpener func(ctx context.Context, cfg SRTConfig) (io.ReadCloser, error)

type SRTReceiver struct {
	cfg      SRTConfig
	streamRx *StreamReceiver
}

func NewSRTReceiver(cfg SRTConfig, onFrame FrameHandler) (*SRTReceiver, error) {
	return NewSRTReceiverWithOpener(cfg, defaultSRTConnOpener, onFrame)
}

func NewSRTReceiverWithOpener(cfg SRTConfig, opener SRTConnOpener, onFrame FrameHandler) (*SRTReceiver, error) {
	if err := cfg.Validate(); err != nil {
		return nil, err
	}
	if opener == nil {
		return nil, fmt.Errorf("SRT opener must not be nil")
	}
	src := cfg.SourceLabel
	if src == "" {
		src = cfg.URL
	}
	streamRx, err := NewStreamReceiver(StreamReceiverConfig{SourceLabel: src}, func(ctx context.Context) (io.ReadCloser, error) {
		return opener(ctx, cfg)
	}, onFrame)
	if err != nil {
		return nil, err
	}
	return &SRTReceiver{cfg: cfg, streamRx: streamRx}, nil
}

func (r *SRTReceiver) Start(ctx context.Context) error { return r.streamRx.Start(ctx) }
func (r *SRTReceiver) Stop() error                     { return r.streamRx.Stop() }