package objects

import "math"
import "strconv"
import "git.tebibyte.media/tomo/tomo"
import "git.tebibyte.media/tomo/tomo/text"
import "git.tebibyte.media/tomo/tomo/input"
import "git.tebibyte.media/tomo/tomo/event"
import "git.tebibyte.media/tomo/objects/layouts"

var _ tomo.Object = new(NumberInput)

// NumberInput is an editable text box which accepts only numbers, and has
// controls to increment and decrement its value.
type NumberInput struct {
	box       tomo.ContainerBox
	input     *TextInput
	increment *Button
	decrement *Button
	on struct {
		valueChange event.FuncBroadcaster
		confirm     event.FuncBroadcaster
	}
}

// NewNumberInput creates a new number input with the specified value.
func NewNumberInput (value float64) *NumberInput {
	numberInput := &NumberInput {
		box:       tomo.NewContainerBox(),
		input:     NewTextInput(""),
		increment: NewButton(""),
		decrement: NewButton(""),
	}
	numberInput.box.SetRole(tomo.R("objects", "NumberInput"))
	numberInput.box.Add(numberInput.input)
	numberInput.box.Add(numberInput.decrement)
	numberInput.box.Add(numberInput.increment)
	numberInput.box.SetAttr(tomo.ALayout(layouts.Row { true, false, false }))
	numberInput.increment.SetIcon(tomo.IconValueIncrement)
	numberInput.decrement.SetIcon(tomo.IconValueDecrement)
	
	numberInput.SetValue(value)
	
	numberInput.box.OnScroll(numberInput.handleScroll)
	numberInput.box.OnKeyDown(numberInput.handleKeyDown)
	numberInput.box.OnKeyUp(numberInput.handleKeyUp)
	numberInput.input.OnConfirm(numberInput.handleConfirm)
	numberInput.input.OnValueChange(numberInput.on.valueChange.Broadcast)
	numberInput.increment.OnClick(func () { numberInput.shift( 1) })
	numberInput.decrement.OnClick(func () { numberInput.shift(-1) })
	return numberInput
}

// GetBox returns the underlying box.
func (this *NumberInput) GetBox () tomo.Box {
	return this.box
}

// SetFocused sets whether or not this number input has keyboard focus. If set
// to true, this method will steal focus away from whichever object currently
// has focus.
func (this *NumberInput) SetFocused (focused bool) {
	this.input.SetFocused(focused)
}

// Select sets the text cursor or selection.
func (this *NumberInput) Select (dot text.Dot) {
	this.input.Select(dot)
}

// Dot returns the text cursor or selection.
func (this *NumberInput) Dot () text.Dot {
	return this.input.Dot()
}

// Value returns the value of the input.
func (this *NumberInput) Value () float64 {
	value, _ := strconv.ParseFloat(this.input.Value(), 64)
	return value
}

// SetValue sets the value of the input.
func (this *NumberInput) SetValue (value float64) {
	this.input.SetValue(strconv.FormatFloat(value, 'g', -1, 64))
}

// OnValueChange specifies a function to be called when the user edits the input
// value.
func (this *NumberInput) OnValueChange (callback func ()) event.Cookie {
	return this.on.valueChange.Connect(callback)
}

// OnConfirm specifies a function to be called when the user presses enter within
// the number input.
func (this *NumberInput) OnConfirm (callback func ()) event.Cookie {
	return this.on.confirm.Connect(callback)
}

func (this *NumberInput) shift (by int) {
	this.SetValue(this.Value() + float64(by))
	this.on.valueChange.Broadcast()
}

func (this *NumberInput) handleKeyDown (key input.Key, numpad bool) bool {
	switch key {
	case input.KeyUp:
		this.shift(1)
		return true
	case input.KeyDown:
		this.shift(-1)
		return true
	}
	return false
}

func (this *NumberInput) handleKeyUp (key input.Key, numpad bool) bool {
	switch key {
	case input.KeyUp:   return true
	case input.KeyDown: return true
	}
	return false
}

func (this *NumberInput) handleScroll (x, y float64) bool {
	if x == 0 {
		this.shift(-int(math.Round(y)))
		return true
	}
	return false
}

func (this *NumberInput) handleConfirm () {
	this.SetValue(this.Value())
	this.on.confirm.Broadcast()
}