package dom

import (
	"time"

	"github.com/gopherjs/gopherjs/js"
)

func WrapEvent(o *js.Object) Event {
	return wrapEvent(o)
}

func wrapEvent(o *js.Object) Event {
	if o == nil || o == js.Undefined {
		return nil
	}
	ev := &BasicEvent{o}
	c := o.Get("constructor")
	switch c {
	case js.Global.Get("AnimationEvent"):
		return &AnimationEvent{ev}
	case js.Global.Get("AudioProcessingEvent"):
		return &AudioProcessingEvent{ev}
	case js.Global.Get("BeforeInputEvent"):
		return &BeforeInputEvent{ev}
	case js.Global.Get("BeforeUnloadEvent"):
		return &BeforeUnloadEvent{ev}
	case js.Global.Get("BlobEvent"):
		return &BlobEvent{ev}
	case js.Global.Get("ClipboardEvent"):
		return &ClipboardEvent{ev}
	case js.Global.Get("CloseEvent"):
		return &CloseEvent{BasicEvent: ev}
	case js.Global.Get("CompositionEvent"):
		return &CompositionEvent{ev}
	case js.Global.Get("CSSFontFaceLoadEvent"):
		return &CSSFontFaceLoadEvent{ev}
	case js.Global.Get("CustomEvent"):
		return &CustomEvent{ev}
	case js.Global.Get("DeviceLightEvent"):
		return &DeviceLightEvent{ev}
	case js.Global.Get("DeviceMotionEvent"):
		return &DeviceMotionEvent{ev}
	case js.Global.Get("DeviceOrientationEvent"):
		return &DeviceOrientationEvent{ev}
	case js.Global.Get("DeviceProximityEvent"):
		return &DeviceProximityEvent{ev}
	case js.Global.Get("DOMTransactionEvent"):
		return &DOMTransactionEvent{ev}
	case js.Global.Get("DragEvent"):
		return &DragEvent{ev}
	case js.Global.Get("EditingBeforeInputEvent"):
		return &EditingBeforeInputEvent{ev}
	case js.Global.Get("ErrorEvent"):
		return &ErrorEvent{ev}
	case js.Global.Get("FocusEvent"):
		return &FocusEvent{ev}
	case js.Global.Get("GamepadEvent"):
		return &GamepadEvent{ev}
	case js.Global.Get("HashChangeEvent"):
		return &HashChangeEvent{ev}
	case js.Global.Get("IDBVersionChangeEvent"):
		return &IDBVersionChangeEvent{ev}
	case js.Global.Get("KeyboardEvent"):
		return &KeyboardEvent{BasicEvent: ev}
	case js.Global.Get("MediaStreamEvent"):
		return &MediaStreamEvent{ev}
	case js.Global.Get("MessageEvent"):
		return &MessageEvent{BasicEvent: ev}
	case js.Global.Get("MouseEvent"):
		return &MouseEvent{UIEvent: &UIEvent{ev}}
	case js.Global.Get("MutationEvent"):
		return &MutationEvent{ev}
	case js.Global.Get("OfflineAudioCompletionEvent"):
		return &OfflineAudioCompletionEvent{ev}
	case js.Global.Get("PageTransitionEvent"):
		return &PageTransitionEvent{ev}
	case js.Global.Get("PointerEvent"):
		return &PointerEvent{ev}
	case js.Global.Get("PopStateEvent"):
		return &PopStateEvent{ev}
	case js.Global.Get("ProgressEvent"):
		return &ProgressEvent{ev}
	case js.Global.Get("RelatedEvent"):
		return &RelatedEvent{ev}
	case js.Global.Get("RTCPeerConnectionIceEvent"):
		return &RTCPeerConnectionIceEvent{ev}
	case js.Global.Get("SensorEvent"):
		return &SensorEvent{ev}
	case js.Global.Get("StorageEvent"):
		return &StorageEvent{ev}
	case js.Global.Get("SVGEvent"):
		return &SVGEvent{ev}
	case js.Global.Get("SVGZoomEvent"):
		return &SVGZoomEvent{ev}
	case js.Global.Get("TimeEvent"):
		return &TimeEvent{ev}
	case js.Global.Get("TouchEvent"):
		return &TouchEvent{ev}
	case js.Global.Get("TrackEvent"):
		return &TrackEvent{ev}
	case js.Global.Get("TransitionEvent"):
		return &TransitionEvent{ev}
	case js.Global.Get("UIEvent"):
		return &UIEvent{ev}
	case js.Global.Get("UserProximityEvent"):
		return &UserProximityEvent{ev}
	case js.Global.Get("WheelEvent"):
		return &WheelEvent{BasicEvent: ev}
	default:
		return ev
	}
}

const (
	EvPhaseNone      = 0
	EvPhaseCapturing = 1
	EvPhaseAtTarget  = 2
	EvPhaseBubbling  = 3
)

type Event interface {
	Bubbles() bool
	Cancelable() bool
	CurrentTarget() Element
	DefaultPrevented() bool
	EventPhase() int
	Target() Element
	Timestamp() time.Time
	Type() string
	PreventDefault()
	StopImmediatePropagation()
	StopPropagation()
	Underlying() *js.Object
}

// Type BasicEvent implements the Event interface and is embedded by
// concrete event types.
type BasicEvent struct{ *js.Object }

func (ev *BasicEvent) Bubbles() bool {
	return ev.Get("bubbles").Bool()
}

func (ev *BasicEvent) Cancelable() bool {
	return ev.Get("cancelable").Bool()
}

func (ev *BasicEvent) CurrentTarget() Element {
	return wrapElement(ev.Get("currentTarget"))
}

func (ev *BasicEvent) DefaultPrevented() bool {
	return ev.Get("defaultPrevented").Bool()
}

func (ev *BasicEvent) EventPhase() int {
	return ev.Get("eventPhase").Int()
}

func (ev *BasicEvent) Target() Element {
	return wrapElement(ev.Get("target"))
}

func (ev *BasicEvent) Timestamp() time.Time {
	ms := ev.Get("timeStamp").Int()
	s := ms / 1000
	ns := (ms % 1000 * 1e6)
	return time.Unix(int64(s), int64(ns))
}

func (ev *BasicEvent) Type() string {
	return ev.Get("type").String()
}

func (ev *BasicEvent) PreventDefault() {
	ev.Call("preventDefault")
}

func (ev *BasicEvent) StopImmediatePropagation() {
	ev.Call("stopImmediatePropagation")
}

func (ev *BasicEvent) StopPropagation() {
	ev.Call("stopPropagation")
}

func (ev *BasicEvent) Underlying() *js.Object {
	return ev.Object
}

type AnimationEvent struct{ *BasicEvent }
type AudioProcessingEvent struct{ *BasicEvent }
type BeforeInputEvent struct{ *BasicEvent }
type BeforeUnloadEvent struct{ *BasicEvent }
type BlobEvent struct{ *BasicEvent }
type ClipboardEvent struct{ *BasicEvent }

type CloseEvent struct {
	*BasicEvent
	Code     int    `js:"code"`
	Reason   string `js:"reason"`
	WasClean bool   `js:"wasClean"`
}

type CompositionEvent struct{ *BasicEvent }
type CSSFontFaceLoadEvent struct{ *BasicEvent }
type CustomEvent struct{ *BasicEvent }
type DeviceLightEvent struct{ *BasicEvent }
type DeviceMotionEvent struct{ *BasicEvent }
type DeviceOrientationEvent struct{ *BasicEvent }
type DeviceProximityEvent struct{ *BasicEvent }
type DOMTransactionEvent struct{ *BasicEvent }
type DragEvent struct{ *BasicEvent }
type EditingBeforeInputEvent struct{ *BasicEvent }
type ErrorEvent struct{ *BasicEvent }
type FocusEvent struct{ *BasicEvent }
type GamepadEvent struct{ *BasicEvent }
type HashChangeEvent struct{ *BasicEvent }
type IDBVersionChangeEvent struct{ *BasicEvent }

const (
	KeyLocationStandard = 0
	KeyLocationLeft     = 1
	KeyLocationRight    = 2
	KeyLocationNumpad   = 3
)

type KeyboardEvent struct {
	*BasicEvent
	AltKey        bool   `js:"altKey"`
	CharCode      int    `js:"charCode"`
	CtrlKey       bool   `js:"ctrlKey"`
	Key           string `js:"key"`
	KeyIdentifier string `js:"keyIdentifier"`
	KeyCode       int    `js:"keyCode"`
	Locale        string `js:"locale"`
	Location      int    `js:"location"`
	KeyLocation   int    `js:"keyLocation"`
	MetaKey       bool   `js:"metaKey"`
	Repeat        bool   `js:"repeat"`
	ShiftKey      bool   `js:"shiftKey"`
}

func (ev *KeyboardEvent) ModifierState(mod string) bool {
	return ev.Call("getModifierState", mod).Bool()
}

type MediaStreamEvent struct{ *BasicEvent }

type MessageEvent struct {
	*BasicEvent
	Data *js.Object `js:"data"`
}

type MouseEvent struct {
	*UIEvent
	AltKey    bool `js:"altKey"`
	Button    int  `js:"button"`
	ClientX   int  `js:"clientX"`
	ClientY   int  `js:"clientY"`
	CtrlKey   bool `js:"ctrlKey"`
	MetaKey   bool `js:"metaKey"`
	MovementX int  `js:"movementX"`
	MovementY int  `js:"movementY"`
	ScreenX   int  `js:"screenX"`
	ScreenY   int  `js:"screenY"`
	ShiftKey  bool `js:"shiftKey"`
}

func (ev *MouseEvent) RelatedTarget() Element {
	return wrapElement(ev.Get("target"))
}

func (ev *MouseEvent) ModifierState(mod string) bool {
	return ev.Call("getModifierState", mod).Bool()
}

type MutationEvent struct{ *BasicEvent }
type OfflineAudioCompletionEvent struct{ *BasicEvent }
type PageTransitionEvent struct{ *BasicEvent }
type PointerEvent struct{ *BasicEvent }
type PopStateEvent struct{ *BasicEvent }
type ProgressEvent struct{ *BasicEvent }
type RelatedEvent struct{ *BasicEvent }
type RTCPeerConnectionIceEvent struct{ *BasicEvent }
type SensorEvent struct{ *BasicEvent }
type StorageEvent struct{ *BasicEvent }
type SVGEvent struct{ *BasicEvent }
type SVGZoomEvent struct{ *BasicEvent }
type TimeEvent struct{ *BasicEvent }
type TouchEvent struct{ *BasicEvent }
type TrackEvent struct{ *BasicEvent }
type TransitionEvent struct{ *BasicEvent }
type UIEvent struct{ *BasicEvent }
type UserProximityEvent struct{ *BasicEvent }

const (
	DeltaPixel = 0
	DeltaLine  = 1
	DeltaPage  = 2
)

type WheelEvent struct {
	*BasicEvent
	DeltaX    float64 `js:"deltaX"`
	DeltaY    float64 `js:"deltaY"`
	DeltaZ    float64 `js:"deltaZ"`
	DeltaMode int     `js:"deltaMode"`
}

type EventTarget interface {
	// AddEventListener adds a new event listener and returns the
	// wrapper function it generated. If using RemoveEventListener,
	// that wrapper has to be used.
	AddEventListener(typ string, useCapture bool, listener func(Event)) func(*js.Object)
	RemoveEventListener(typ string, useCapture bool, listener func(*js.Object))
	// DispatchEvent() // TODO
}