package todoist

import (
	"github.com/darkSasori/todoist"
	"github.com/gdamore/tcell"
	"github.com/rivo/tview"
	"github.com/wtfutil/wtf/wtf"
)

const HelpText = `
 Keyboard commands for Todoist:

   /: Show/hide this help window
   c: Close the selected item
   d: Delete the selected item
   h: Previous Todoist list
   j: Select the next item in the list
   k: Select the previous item in the list
   l: Next Todoist list
   r: Refresh the todo list data

   arrow down: Select the next item in the list
   arrow left: Previous Todoist list
   arrow right: Next Todoist list
   arrow up: Select the previous item in the list
`

// A Widget represents a Todoist widget
type Widget struct {
	wtf.HelpfulWidget
	wtf.KeyboardWidget
	wtf.TextWidget

	idx      int
	projects []*Project
	settings *Settings
}

// NewWidget creates a new instance of a widget
func NewWidget(app *tview.Application, pages *tview.Pages, settings *Settings) *Widget {
	widget := Widget{
		HelpfulWidget:  wtf.NewHelpfulWidget(app, pages, HelpText),
		KeyboardWidget: wtf.NewKeyboardWidget(),
		TextWidget:     wtf.NewTextWidget(app, settings.common, true),

		settings: settings,
	}

	widget.loadAPICredentials()
	widget.loadProjects()

	widget.initializeKeyboardControls()
	widget.View.SetInputCapture(widget.InputCapture)

	widget.HelpfulWidget.SetView(widget.View)

	return &widget
}

/* -------------------- Exported Functions -------------------- */

func (widget *Widget) CurrentProject() *Project {
	return widget.ProjectAt(widget.idx)
}

func (widget *Widget) ProjectAt(idx int) *Project {
	if len(widget.projects) == 0 {
		return nil
	}

	return widget.projects[idx]
}

func (w *Widget) NextProject() {
	w.idx = w.idx + 1
	if w.idx == len(w.projects) {
		w.idx = 0
	}

	w.display()
}

func (w *Widget) PreviousProject() {
	w.idx = w.idx - 1
	if w.idx < 0 {
		w.idx = len(w.projects) - 1
	}

	w.display()
}

func (w *Widget) Refresh() {
	if w.Disabled() || w.CurrentProject() == nil {
		return
	}

	w.display()
}

/* -------------------- Keyboard Movement -------------------- */

// Down selects the next item in the list
func (w *Widget) Down() {
	w.CurrentProject().down()
	w.display()
}

// Up selects the previous item in the list
func (w *Widget) Up() {
	w.CurrentProject().up()
	w.display()
}

// Close closes the currently-selected task in the currently-selected project
func (w *Widget) Close() {
	w.CurrentProject().closeSelectedTask()

	if w.CurrentProject().isLast() {
		w.Up()
		return
	}

	w.Down()
}

// Delete deletes the currently-selected task in the currently-selected project
func (w *Widget) Delete() {
	w.CurrentProject().deleteSelectedTask()

	if w.CurrentProject().isLast() {
		w.Up()
		return
	}

	w.Down()
}

/* -------------------- Unexported Functions -------------------- */

func (widget *Widget) loadAPICredentials() {
	todoist.Token = widget.settings.apiKey
}

func (widget *Widget) loadProjects() {
	projects := []*Project{}

	for _, id := range widget.settings.projects {
		proj := NewProject(id.(int))
		projects = append(projects, proj)
	}

	widget.projects = projects
}

func (w *Widget) vimBindings(event *tcell.EventKey) tcell.Key {
	switch string(event.Rune()) {
	case "h":
		return tcell.KeyLeft
	case "l":
		return tcell.KeyRight
	case "k":
		return tcell.KeyUp
	case "j":
		return tcell.KeyDown
	}
	return event.Key()
}