package ports

import "time"

// Mods carries input → core modifier flags.
type Mods uint8

const (
	ModShift Mods = 1 << iota
	ModCtrl
	ModAlt
	ModSuper
)

// InputEvent carries input → core notifications.
type InputEvent interface{ inputEvent() }

// KeyEvent carries input → core key transitions; Keysym is an xkb keysym name.
// Keycode is the evdev code (xkb keycode - 8) and State the xkb modifier state
// after this transition; wayland forwards both to clients unchanged.
type KeyEvent struct {
	Keysym string
	// Base is the key's unshifted keysym in the active layout, so Cmd+Shift+1
	// still matches a cmd+shift+1 bind although it prints exclam.
	Base     string
	Mods     Mods
	Pressed  bool
	TimeMsec uint32
	Keycode  uint32
	State    ModState
}

// ModState is the serialized xkb modifier state sent in wl_keyboard.modifiers.
type ModState struct{ Depressed, Latched, Locked, Group uint32 }

func (KeyEvent) inputEvent() {}

// PointerMotion uses global layout coordinates in logical pixels (see OutputPlacement).
// DX and DY are the accelerated logical deltas and UnaccelDX, UnaccelDY the
// raw device deltas; all four are 0 for absolute devices. TimeUsec is the
// device timestamp in microseconds.
type PointerMotion struct {
	X, Y                 float64
	DX, DY               float64
	UnaccelDX, UnaccelDY float64
	TimeMsec             uint32
	TimeUsec             uint64
}

func (PointerMotion) inputEvent() {}

// PointerButton uses evdev button codes (BTN_LEFT is 0x110).
type PointerButton struct {
	Button   uint32
	Pressed  bool
	TimeMsec uint32
}

func (PointerButton) inputEvent() {}

// AxisSource tells how a scroll was made; values match wl_pointer.axis_source.
type AxisSource uint8

const (
	AxisWheel AxisSource = iota
	AxisFinger
	AxisContinuous
)

// ScrollAxis is one scroll direction in a pointer frame. Value is in
// surface pixels; V120 counts wheel detents in 1/120 steps (wheel only).
// Stop ends a finger or continuous scroll on this axis.
type ScrollAxis struct {
	Set   bool
	Value float64
	V120  int32
	Stop  bool
}

// PointerAxis is one scroll frame: Vertical, then Horizontal.
type PointerAxis struct {
	Source               AxisSource
	Vertical, Horizontal ScrollAxis
	TimeMsec             uint32
}

func (PointerAxis) inputEvent() {}

// SwipeBegin starts a three- or four-finger touchpad swipe. Time is the
// device timestamp (CLOCK_MONOTONIC), shared by the updates and the end.
type SwipeBegin struct {
	Fingers int
	Time    time.Duration
}

// SwipeUpdate moves the fingers by the unaccelerated deltas DX, DY
// (touchpad units, as libinput reports them, not natural-scroll inverted).
type SwipeUpdate struct {
	DX, DY float64
	Time   time.Duration
}

// SwipeEnd lifts the fingers. Cancelled is set when libinput cancelled
// the swipe (another finger landed).
type SwipeEnd struct {
	Cancelled bool
	Time      time.Duration
}

func (SwipeBegin) inputEvent()  {}
func (SwipeUpdate) inputEvent() {}
func (SwipeEnd) inputEvent()    {}