package recorder

import (
	"context"
	"net"
	"time"

	"github.com/go-gost/core/logger"
	"github.com/go-gost/core/metrics"
	"github.com/go-gost/core/recorder"
	xmetrics "github.com/go-gost/x/metrics"
)

type tcpRecorderOptions struct {
	recorder string
	timeout  time.Duration
	log      logger.Logger
}

// TCPRecorderOption configures TCPRecorder options.
type TCPRecorderOption func(opts *tcpRecorderOptions)

// RecorderTCPRecorderOption sets the recorder name for metrics labeling.
func RecorderTCPRecorderOption(recorder string) TCPRecorderOption {
	return func(opts *tcpRecorderOptions) {
		opts.recorder = recorder
	}
}

// TimeoutTCPRecorderOption sets the dial timeout for TCP connections.
func TimeoutTCPRecorderOption(timeout time.Duration) TCPRecorderOption {
	return func(opts *tcpRecorderOptions) {
		opts.timeout = timeout
	}
}

// LogTCPRecorderOption sets the logger for the TCP recorder.
func LogTCPRecorderOption(log logger.Logger) TCPRecorderOption {
	return func(opts *tcpRecorderOptions) {
		opts.log = log
	}
}

type tcpRecorder struct {
	recorder string
	addr     string
	dialer   *net.Dialer
	log      logger.Logger
}

// TCPRecorder records data to TCP service.
func TCPRecorder(addr string, opts ...TCPRecorderOption) recorder.Recorder {
	var options tcpRecorderOptions
	for _, opt := range opts {
		opt(&options)
	}

	return &tcpRecorder{
		recorder: options.recorder,
		addr:     addr,
		dialer: &net.Dialer{
			Timeout: options.timeout,
		},
		log: options.log,
	}
}

func (r *tcpRecorder) Record(ctx context.Context, b []byte, opts ...recorder.RecordOption) error {
	xmetrics.GetCounter(xmetrics.MetricRecorderRecordsCounter, metrics.Labels{"recorder": r.recorder}).Inc()

	c, err := r.dialer.DialContext(ctx, "tcp", r.addr)
	if err != nil {
		return err
	}
	defer c.Close()

	for written := 0; written < len(b); {
		n, err := c.Write(b[written:])
		if err != nil {
			return err
		}
		written += n
	}
	return nil
}
