package screen

import (
	"errors"
	"fmt"
	"time"

	"bitbucket.org/hevanto/ui/uiwidget"
	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/data/binding"
	"fyne.io/fyne/v2/layout"
	"fyne.io/fyne/v2/widget"
	xwidget "fyne.io/x/fyne/widget"
)

// The constants for the Widgets
//
// Available yaml options for all widgets:
//   - id: The ID for exporting the widget to code
//   - decorators: The decorators to wrap the widget into
//   - hidden: Wether the widget is hidden or not
type Widget string

const (
	// Button Widget
	//
	// Available yaml options:
	//	- text: The text for the button
	//	- localized: If the text represents a localization key
	//	- icon: The icon for the button
	//	- disabled: Wether the button is disabled or not
	//	- options: Additional options for the button
	//		- alignment: The alignment of the button
	//		- iconPlacement: The icon placement of the button
	//		- importance: The importance of the button
	//	- onclicked: The function to call when the button is clicked
	Button Widget = "Button"

	// Calendar Widget
	//
	// Available yaml options:
	//	- time: The current time to use for the calendar
	//	- timeFormat: The format to use to interpret the time field (default time.DateOnly)
	//	- onDateSelected: The function to call when a date is selected
	Calendar Widget = "Calendar"

	// Checkbox Widget
	//
	// Available yaml options:
	//	- text: The text for the checkbox
	//	- localized: If the text represents a localization key
	//	- binding: The databinding for the checkbox
	//	- checked: The checked state of the checkbox
	//	- disabled: Wether the button is disabled or not
	//	- onChanged: The function to call when the checkbox is changed
	Check Widget = "Check"

	DateEntry Widget = "DateEntry"

	// Entry Widget
	//
	// Available yaml options:
	//	- text: The text for the entry
	//	- localized: If the text represents a localization key
	//	- binding: The databinding for the entry
	//	- placeholder: The placeholder for the entry
	//	- placeholderLocalized: If the placeholder represents a localization key
	//	- multiLine: If the entry is multiline
	//	- disabled: Wether the button is disabled or not
	//	- validator: The validator for the entry
	//	- onValidationChanged: The function to call when the validation changes
	Entry Widget = "Entry"

	// H1 Widget
	//
	// Available yaml options:
	//	- text: The text for the H1
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H1
	//	- options: The options for the H1
	//		- wrapping: The wrapping option for the H1
	//		- truncation: The truncation option for the H1
	H1 Widget = "H1"

	// H2 Widget
	//
	// Available yaml options:
	//	- text: The text for the H2
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H2
	//	- options: The options for the H2
	//		- wrapping: The wrapping option for the H2
	//		- truncation: The truncation option for the H2
	H2 Widget = "H2"

	// H3 Widget
	//
	// Available yaml options:
	//	- text: The text for the H3
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H3
	//	- options: The options for the H3
	//		- wrapping: The wrapping option for the H3
	//		- truncation: The truncation option for the H3
	H3 Widget = "H3"

	// H4 Widget
	//
	// Available yaml options:
	//	- text: The text for the H4
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H4
	//	- options: The options for the H4
	//		- wrapping: The wrapping option for the H4
	//		- truncation: The truncation option for the H4
	H4 Widget = "H4"

	// H5 Widget
	//
	// Available yaml options:
	//	- text: The text for the H5
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H5
	//	- options: The options for the H5
	//		- wrapping: The wrapping option for the H5
	//		- truncation: The truncation option for the H5
	H5 Widget = "H5"

	// H6 Widget
	//
	// Available yaml options:
	//	- text: The text for the H6
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the H6
	//	- options: The options for the H6
	//		- wrapping: The wrapping option for the H6
	//		- truncation: The truncation option for the H6
	H6 Widget = "H6"

	// Icon Widget
	//
	// Available yaml options:
	//	- icon: The icon for the icon
	Icon Widget = "Icon"

	// Label Widget
	//
	// Available yaml options:
	//	- text: The text for the label
	//	- localized: If the text represents a localization key
	// 	- binding: The databinding for the label
	//	- options: The options for the label
	//		- alignment: The alignment option for the label
	//		- wrapping: The wrapping option for the label
	// 		- textStyle: The text style option for the label
	//		- truncation: The truncation option for the label
	Label Widget = "Label"

	// List Widget
	//
	// Available yaml options:
	//	- binding: The databinding for the list
	//	- listLength: The length of the list
	//	- itemTemplate: The item template for the list
	//	- itemRenderer: The item renderer for the list
	//	- onSelect: The on select function for the list
	//	- onUnselect: The on unselect function for the list
	List Widget = "List"

	// Select Widget
	Select Widget = "Select"

	// SelectEntry Widget
	SelectEntry Widget = "SelectEntry"

	// Separator Widget
	Separator Widget = "Separator"

	// Spacer Widget
	Spacer Widget = "Spacer"

	// UpDownLabel Widget
	//
	// Available yaml options:
	//	- binding: The databinding for the up down label
	//	- onUpClicked: The on up clicked function for the up down label
	//	- onDownClicked: The on down clicked function for the up down label
	UpDownLabel Widget = "UpDownLabel"
)

// Build builds a fyne.CanvasObject for the given Widget and Element,
// using the provided ScreenHandler to fetch functions, data bindings, etc.
//
// Arguments:
// - e: The Element to build the Widget for.
// - s: The ScreenHandler to use to fetch functions, data bindings, etc.
//
// Returns the CanvasObject for the widget, the CanvasObject for the decorator,
// and an error if any.
// If no decorators are specified, the widget and decorator will be the same.
func (w Widget) Build(
	e *Element,
	s ScreenHandler,
) (
	widget fyne.CanvasObject,
	decorator fyne.CanvasObject,
	err error,
) {
	e.localize(s)

	switch w {
	case Button:
		widget, err = w.buildButtonWidget(e, s)
	case Calendar:
		widget, err = w.buildCalendarWidget(e, s)
	case Check:
		widget, err = w.buildCheckWidget(e, s)
	case DateEntry:
		widget, err = w.buildDateEntryWidget(e, s)
	case Entry:
		widget, err = w.buildEntryWidget(e, s)
	case H1, H2, H3, H4, H5, H6:
		widget, err = w.buildHeaderLabelWidget(e, s)
	case Icon:
		widget, err = w.buildIconWidget(e, s)
	case Label:
		widget, err = w.buildLabelWidget(e, s)
	case List:
		widget, err = w.buildListWidget(e, s)
	case Select:
		widget, err = w.buildSelectWidget(e, s)
	case SelectEntry:
		widget, err = w.buildSelectEntryWidget(e, s)
	case Separator:
		widget, err = w.buildSeparatorWidget(e, s)
	case Spacer:
		widget, err = w.buildSpacerWidget(e, s)
	case UpDownLabel:
		widget, err = w.buildUpDownLabelWidget(e, s)
	default:
		err = errors.New("invalid widget")
	}
	if err != nil {
		return
	}

	decorator = widget
	if e.Decorators != nil {
		for _, dec := range e.Decorators {
			switch dec {
			case "Border":
				decorator = uiwidget.NewWidgetBorder(decorator)
			}
		}
	}

	if e.Hidden {
		decorator.Hide()
	}
	return
}

func (w Widget) buildButtonWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var btn *widget.Button
	if e.Icon != "" {
		btn = widget.NewButtonWithIcon(
			e.Text, s.GetIcon(e.Icon), s.GetOnClickedHandler(e.OnClicked))
	} else {
		btn = widget.NewButton(e.Text, s.GetOnClickedHandler(e.OnClicked))
	}

	for opt, val := range e.Options {
		switch opt {
		case "alignment":
			btn.Alignment = getButtonAlignment(val)
		case "iconPlacement":
			btn.IconPlacement = getButtonIconPlacement(val)
		case "importance":
			btn.Importance = getImportance(val)
		}
	}

	if e.Disabled {
		btn.Disable()
	}
	c = btn
	return
}

func (w Widget) buildCalendarWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	t := time.Now()
	if e.Time != nil {
		timeFormat := time.DateOnly
		if e.TimeFormat != nil {
			timeFormat = parseTimeFormat(*e.TimeFormat)
		}
		if t, err = time.Parse(timeFormat, *e.Time); err != nil {
			err = fmt.Errorf("CalendarWidget: failed to parse time: %w", err)
			return
		}
	}

	c = xwidget.NewCalendar(t, s.GetOnDateSelectedHandler(e.OnDateSelected))
	return
}

func (w Widget) buildCheckWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var chk *widget.Check
	if e.Binding != "" {
		chk = widget.NewCheckWithData(
			e.Text, s.GetBinding(e.Binding).(binding.Bool))
	} else {
		chk = widget.NewCheck(
			e.Text, s.GetOnCheckChangedHandler(e.OnChanged))
		chk.SetChecked(e.Checked)
	}

	if e.Disabled {
		chk.Disable()
	}
	c = chk
	return
}

func (w Widget) buildDateEntryWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	ent := uiwidget.NewDateEntry()

	if e.OnDateSelected != "" {
		ent.OnDateChanged = s.GetOnDateSelectedHandler(e.OnDateSelected)
	}

	if e.Disabled {
		ent.Disable()
	}
	c = ent
	return
}

func (w Widget) buildEntryWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var ent *widget.Entry
	if e.MultiLine {
		ent = widget.NewMultiLineEntry()
	} else {
		ent = widget.NewEntry()
	}
	if e.Binding != "" {
		ent.Bind(s.GetBinding(e.Binding).(binding.String))
	} else {
		ent.Text = e.Text
	}
	ent.PlaceHolder = e.Placeholder
	if e.Validator != "" {
		ent.Validator = s.GetValidator(e.Validator)
	}
	if e.OnValidationChanged != "" {
		ent.SetOnValidationChanged(s.GetOnValidationChangedHandler(e.OnValidationChanged))
	}

	if e.Disabled {
		ent.Disable()
	}
	c = ent
	return
}

func (w Widget) buildHeaderLabelWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var rt *widget.RichText

	level := 1
	switch e.Widget {
	case H1:
		level = 1
	case H2:
		level = 2
	case H3:
		level = 3
	case H4:
		level = 4
	case H5:
		level = 5
	case H6:
		level = 6
	}
	if e.Binding != "" {
		rt = uiwidget.NewHWithData(level, s.GetBinding(e.Binding).(binding.String))
	} else {
		rt = uiwidget.NewH(level, e.Text)
	}

	for opt, val := range e.Options {
		switch opt {
		case "wrapping":
			rt.Wrapping = getTextWrap(val)
		case "truncation":
			rt.Truncation = getTruncation(val)
		}
	}
	c = rt
	return
}

func (w Widget) buildIconWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	c = widget.NewIcon(s.GetIcon(e.Icon))
	return
}

func (w Widget) buildLabelWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var lbl *widget.Label

	if e.Binding != "" {
		lbl = widget.NewLabelWithData(s.GetBinding(e.Binding).(binding.String))
	} else {
		lbl = widget.NewLabel(e.Text)
	}

	for opt, val := range e.Options {
		switch opt {
		case "alignment":
			lbl.Alignment = getTextAlignment(val)
		case "wrapping":
			lbl.Wrapping = getTextWrap(val)
		case "textStyle":
			lbl.TextStyle = getTextStyle(val)
		case "truncation":
			lbl.Truncation = getTruncation(val)
		case "importance":
			lbl.Importance = getImportance(val)
		}
	}
	c = lbl
	return
}

func (w Widget) buildListWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var lst *widget.List

	if e.Binding != "" {
		lst = widget.NewListWithData(
			s.GetBinding(e.Binding).(binding.DataList),
			s.GetListItemTemplate(e.ItemTemplate),
			s.GetListDataItemRenderer(e.ItemRenderer))
	} else {
		lst = widget.NewList(
			s.GetListLength(e.ListLength),
			s.GetListItemTemplate(e.ItemTemplate),
			s.GetListItemRenderer(e.ItemRenderer))
	}

	if e.OnSelected != "" {
		lst.OnSelected = s.GetOnListItemSelectedHandler(e.OnSelected)
	}
	if e.OnUnselected != "" {
		lst.OnUnselected = s.GetOnListItemUnselectedHandler(e.OnUnselected)
	}
	c = lst
	return
}

func (w Widget) buildSelectWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var slc *widget.Select
	var options []string

	if e.Binding != "" {
		if lst, ok := s.GetBinding(e.SelectOptionsBinding).(binding.StringList); ok {
			options, _ = lst.Get()
		}
	} else {
		options = e.SelectOptions
	}

	slc = widget.NewSelect(options,
		s.GetOnOptionSelectedHandler(e.OnOptionSelected))
	slc.PlaceHolder = e.Placeholder

	for opt, val := range e.Options {
		switch opt {
		case "alignment":
			slc.Alignment = getTextAlignment(val)
		}
	}

	if e.Disabled {
		slc.Disable()
	}
	c = slc
	return
}

func (w Widget) buildSelectEntryWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var slc *widget.SelectEntry
	var options []string

	if e.SelectOptionsBinding != "" {
		if lst, ok := s.GetBinding(e.SelectOptionsBinding).(binding.StringList); ok {
			options, _ = lst.Get()
			lst.AddListener(binding.NewDataListener(func() {
				options, _ = lst.Get()
				if slc != nil {
					slc.SetOptions(options)
				}
			}))
		}
	} else {
		options = e.SelectOptions
	}

	slc = widget.NewSelectEntry(options)

	if e.Binding != "" {
		slc.Bind(s.GetBinding(e.Binding).(binding.String))
	} else {
		slc.Text = e.Text
	}
	slc.PlaceHolder = e.Placeholder
	if e.Validator != "" {
		slc.Validator = s.GetValidator(e.Validator)
	}
	if e.OnValidationChanged != "" {
		slc.SetOnValidationChanged(s.GetOnValidationChangedHandler(e.OnValidationChanged))
	}

	if e.Disabled {
		slc.Disable()
	}
	c = slc
	return
}

func (w Widget) buildSeparatorWidget(
	_ *Element,
	_ ScreenHandler,
) (c fyne.CanvasObject, err error) {
	sep := widget.NewSeparator()
	c = sep
	return
}

func (w Widget) buildSpacerWidget(
	e *Element,
	_ ScreenHandler,
) (c fyne.CanvasObject, err error) {
	spc := &layout.Spacer{
		FixHorizontal: e.FixHorizontal,
		FixVertical:   e.FixVertical,
	}
	c = spc
	return
}

func (w Widget) buildUpDownLabelWidget(
	e *Element,
	s ScreenHandler,
) (c fyne.CanvasObject, err error) {
	var minSize *fyne.Size
	if e.MinSize != nil {
		minSize = &fyne.Size{Width: e.MinSize.Width, Height: e.MinSize.Height}
	}
	btn := uiwidget.NewUpDownLabelWithData(
		minSize,
		s.GetBinding(e.Binding).(binding.String),
		s.GetOnClickedHandler(e.OnUpClicked),
		s.GetOnClickedHandler(e.OnDownClicked))
	c = btn
	return
}

func getButtonAlignment(v any) widget.ButtonAlign {
	switch v.(string) {
	case "ButtonAlignLeading":
		return widget.ButtonAlignLeading
	case "ButtonAlignTrailing":
		return widget.ButtonAlignTrailing
	}
	return widget.ButtonAlignCenter
}

func getButtonIconPlacement(v any) widget.ButtonIconPlacement {
	if v.(string) == "ButtonIconTrailingText" {
		return widget.ButtonIconTrailingText
	}
	return widget.ButtonIconLeadingText
}

func getImportance(v any) widget.Importance {
	switch v.(string) {
	case "LowImportance":
		return widget.LowImportance
	case "HighImportance":
		return widget.HighImportance
	case "DangerImportance":
		return widget.DangerImportance
	case "WarningImportance":
		return widget.WarningImportance
	case "SuccessImportance":
		return widget.SuccessImportance
	}
	return widget.MediumImportance
}

func getTextAlignment(v any) fyne.TextAlign {
	switch v.(string) {
	case "TextAlignCenter":
		return fyne.TextAlignCenter
	case "TextAlignTrailing":
		return fyne.TextAlignTrailing
	}
	return fyne.TextAlignLeading
}

func getTextStyle(v any) fyne.TextStyle {
	var ts fyne.TextStyle

	props, ok := v.(map[string]any)
	if !ok {
		return ts
	}

	for key, val := range props {
		switch key {
		case "bold":
			ts.Bold, _ = val.(bool)
		case "italic":
			ts.Italic, _ = val.(bool)
		case "monospace":
			ts.Monospace, _ = val.(bool)
		case "symbol":
			ts.Symbol, _ = val.(bool)
		case "tabWidth":
			ts.TabWidth, _ = val.(int)
		}
	}
	return ts
}

func getTextWrap(v any) fyne.TextWrap {
	switch v.(string) {
	case "TextWrapBreak":
		return fyne.TextWrapBreak
	case "TextWrapWord":
		return fyne.TextWrapWord
	}
	return fyne.TextWrapOff
}

func getTruncation(v any) fyne.TextTruncation {
	switch v.(string) {
	case "TextTruncateClip":
		return fyne.TextTruncateClip
	case "TextTruncateEllipsis":
		return fyne.TextTruncateEllipsis
	}
	return fyne.TextTruncateOff
}

func parseTimeFormat(format string) string {
	switch format {
	case "ANSIC":
		return time.ANSIC
	case "UnixDate":
		return time.UnixDate
	case "RubyDate":
		return time.RubyDate
	case "RFC822":
		return time.RFC822
	case "RFC822Z":
		return time.RFC822Z
	case "RFC850":
		return time.RFC850
	case "RFC1123":
		return time.RFC1123
	case "RFC1123Z":
		return time.RFC1123Z
	case "RFC3339":
		return time.RFC3339
	case "RFC3339Nano":
		return time.RFC3339Nano
	case "Kitchen":
		return time.Kitchen
	case "Stamp":
		return time.Stamp
	case "StampMilli":
		return time.StampMilli
	case "StampMicro":
		return time.StampMicro
	case "StampNano":
		return time.StampNano
	case "DateTime":
		return time.DateTime
	case "DateOnly":
		return time.DateOnly
	case "TimeOnly":
		return time.TimeOnly
	default:
		return format
	}
}