//go:build linux

// Wayland screen capture using PipeWire and xdg-desktop-portal.
package backends

import (
	"fmt"
	"image"

	"git.cloonar.com/openclawd/iso-bot/pkg/engine/capture"
)

// WaylandConfig holds configuration for Wayland screen capture.
type WaylandConfig struct {
	// Output is the Wayland output name to capture (e.g., "DP-1", "HDMI-A-1").
	// If empty, captures the primary output.
	Output string `yaml:"output"`

	// UsePipeWire enables PipeWire-based capture for better performance.
	// Falls back to xdg-desktop-portal screencasting if false.
	UsePipeWire bool `yaml:"use_pipewire"`

	// WindowTitle attempts to capture a specific window (if supported).
	// Note: Wayland has limited window-specific capture due to security model.
	WindowTitle string `yaml:"window_title"`

	// Framerate sets the desired capture framerate.
	Framerate int `yaml:"framerate"`
}

// WaylandSource captures screen content on Wayland using PipeWire/xdg-desktop-portal.
type WaylandSource struct {
	config      WaylandConfig
	pipeWireCtx uintptr // PipeWire context
	stream      uintptr // PipeWire stream
	width       int
	height      int
	active      bool
}

// NewWaylandSource creates a Wayland screen capture source.
func NewWaylandSource(configMap map[string]interface{}) (capture.Source, error) {
	var config WaylandConfig

	// Extract config from map
	if output, ok := configMap["output"].(string); ok {
		config.Output = output
	}
	if usePW, ok := configMap["use_pipewire"].(bool); ok {
		config.UsePipeWire = usePW
	} else {
		config.UsePipeWire = true // Default to PipeWire
	}
	if title, ok := configMap["window_title"].(string); ok {
		config.WindowTitle = title
	}
	if fps, ok := configMap["framerate"].(int); ok {
		config.Framerate = fps
	} else {
		config.Framerate = 30 // Default framerate
	}

	return &WaylandSource{
		config: config,
	}, nil
}

// Name returns a description of this capture source.
func (w *WaylandSource) Name() string {
	if w.config.Output != "" {
		return fmt.Sprintf("Wayland Output: %s", w.config.Output)
	}
	if w.config.WindowTitle != "" {
		return fmt.Sprintf("Wayland Window: %s", w.config.WindowTitle)
	}
	return "Wayland Screen Capture"
}

// Capture grabs a single frame from Wayland.
func (w *WaylandSource) Capture() (image.Image, error) {
	if !w.active {
		if err := w.startCapture(); err != nil {
			return nil, fmt.Errorf("failed to start Wayland capture: %w", err)
		}
	}

	// TODO: Implement Wayland screen capture
	// 1. Use xdg-desktop-portal ScreenCast interface to request screen sharing
	// 2. Get PipeWire stream from portal response
	// 3. Connect to PipeWire stream and read video buffers
	// 4. Convert PipeWire buffer to Go image.Image
	return nil, fmt.Errorf("Wayland capture not implemented yet")
}

// CaptureRegion grabs a sub-region of the screen.
func (w *WaylandSource) CaptureRegion(r capture.Region) (image.Image, error) {
	// TODO: Implement region capture
	// Capture full screen then crop to region, as Wayland doesn't support partial capture
	fullFrame, err := w.Capture()
	if err != nil {
		return nil, err
	}

	// Crop the image to the specified region
	bounds := image.Rect(r.X, r.Y, r.X+r.Width, r.Y+r.Height)
	return fullFrame.(interface{
		SubImage(r image.Rectangle) image.Image
	}).SubImage(bounds), nil
}

// Size returns the screen dimensions.
func (w *WaylandSource) Size() (width, height int) {
	// TODO: Get actual screen size from Wayland output info
	return w.width, w.height
}

// Close releases Wayland resources.
func (w *WaylandSource) Close() error {
	w.active = false
	// TODO: Close PipeWire stream and context
	return nil
}

// startCapture initiates the screen capture session.
func (w *WaylandSource) startCapture() error {
	// TODO: Implement capture initialization
	// 1. Connect to xdg-desktop-portal via D-Bus
	// 2. Call CreateSession on org.freedesktop.portal.ScreenCast interface
	// 3. Configure capture source (screen or window)
	// 4. Start capture session
	// 5. Extract PipeWire node ID from response
	// 6. Connect to PipeWire and setup stream callbacks
	w.active = true
	return fmt.Errorf("Wayland capture initialization not implemented")
}

// initPipeWire sets up PipeWire connection and stream.
func (w *WaylandSource) initPipeWire(nodeID uint32) error {
	// TODO: Implement PipeWire initialization
	// 1. Create PipeWire main loop and context
	// 2. Create stream with video format constraints
	// 3. Connect stream to the portal-provided node
	// 4. Setup stream callbacks for buffer processing
	return fmt.Errorf("PipeWire initialization not implemented")
}

// requestScreenCast uses xdg-desktop-portal to request screen access.
func (w *WaylandSource) requestScreenCast() (uint32, error) {
	// TODO: Implement D-Bus communication with xdg-desktop-portal
	// 1. Create D-Bus connection
	// 2. Call org.freedesktop.portal.ScreenCast.CreateSession
	// 3. Call SelectSources with appropriate source types
	// 4. Call Start to begin capture
	// 5. Parse response to get PipeWire node ID
	return 0, fmt.Errorf("ScreenCast portal request not implemented")
}

// processPipeWireBuffer converts PipeWire video buffer to image.
func (w *WaylandSource) processPipeWireBuffer(buffer uintptr) (image.Image, error) {
	// TODO: Implement buffer processing
	// 1. Extract video format info (width, height, stride, pixel format)
	// 2. Map buffer memory
	// 3. Convert pixel data to image.RGBA
	// 4. Handle different pixel formats (BGRA, RGBA, etc.)
	return nil, fmt.Errorf("PipeWire buffer processing not implemented")
}