// Package encoding handles video encoding with software encoders.
package encoding

import (
	"os/exec"
)

// Encoder represents a video encoder.
type Encoder interface {
	Name() string
	Codec() string
	Available() bool
	BuildCommand(config *EncodeConfig) *exec.Cmd
}

// EncodeConfig holds configuration for video encoding.
type EncodeConfig struct {
	InputPattern string  // Input file pattern (e.g., "frame_%04d.exr")
	OutputPath   string  // Output file path
	StartFrame   int     // Starting frame number
	FrameRate    float64 // Frame rate
	WorkDir      string  // Working directory
	UseAlpha     bool    // Whether to preserve alpha channel
	TwoPass      bool    // Whether to use 2-pass encoding
	SourceFormat string  // Source format: "exr" or "png" (defaults to "exr")
	PreserveHDR  bool    // Whether to preserve HDR range for EXR (uses HLG with bt709 primaries)
}

// Selector selects the software encoder.
type Selector struct {
	h264Encoders []Encoder
	av1Encoders  []Encoder
	vp9Encoders  []Encoder
}

// NewSelector creates a new encoder selector with software encoders.
func NewSelector() *Selector {
	s := &Selector{}
	s.detectEncoders()
	return s
}

func (s *Selector) detectEncoders() {
	// Use software encoding only - reliable and avoids hardware-specific colorspace issues
	s.h264Encoders = []Encoder{
		&SoftwareEncoder{codec: "libx264"},
	}

	s.av1Encoders = []Encoder{
		&SoftwareEncoder{codec: "libaom-av1"},
	}

	s.vp9Encoders = []Encoder{
		&SoftwareEncoder{codec: "libvpx-vp9"},
	}
}

// SelectH264 returns the software H.264 encoder.
func (s *Selector) SelectH264() Encoder {
	return &SoftwareEncoder{codec: "libx264"}
}

// SelectAV1 returns the software AV1 encoder.
func (s *Selector) SelectAV1() Encoder {
	return &SoftwareEncoder{codec: "libaom-av1"}
}

// SelectVP9 returns the software VP9 encoder.
func (s *Selector) SelectVP9() Encoder {
	return &SoftwareEncoder{codec: "libvpx-vp9"}
}