package scan

import (
	"fmt"
	"strings"

	"github.com/Ullaakut/cameradar/v6"
	"github.com/Ullaakut/cameradar/v6/internal/scan/masscan"
	"github.com/Ullaakut/cameradar/v6/internal/scan/nmap"
	"github.com/Ullaakut/cameradar/v6/internal/scan/skip"
)

// Supported discovery backends.
const (
	ScannerNmap    = "nmap"
	ScannerMasscan = "masscan"
)

// Config configures how Cameradar discovers RTSP streams.
type Config struct {
	SkipScan  bool
	Targets   []string
	Ports     []string
	ScanSpeed int16
	Scanner   string
}

// Reporter reports scan progress and debug information.
type Reporter interface {
	Debug(step cameradar.Step, message string)
	Progress(step cameradar.Step, message string)
}

// New builds a stream scanner based on the provided configuration.
func New(config Config, reporter Reporter) (cameradar.StreamScanner, error) {
	expandedTargets, err := expandTargetsForScan(config.Targets)
	if err != nil {
		return nil, err
	}

	if config.SkipScan {
		return skip.New(expandedTargets, config.Ports), nil
	}

	scanner := strings.ToLower(strings.TrimSpace(config.Scanner))
	if scanner == "" {
		scanner = ScannerNmap
	}

	switch scanner {
	case ScannerNmap:
		return nmap.New(config.ScanSpeed, expandedTargets, config.Ports, reporter)
	case ScannerMasscan:
		return masscan.New(expandedTargets, config.Ports, reporter)
	default:
		return nil, fmt.Errorf("unsupported scanner %q", scanner)
	}
}