package ui
import (
"sync/atomic"
"github.com/gdamore/tcell"
)
type UI struct {
Content DrawableInteractive
exit atomic.Value // bool
ctx *Context
screen tcell.Screen
popover *Popover
tcEvents chan tcell.Event
invalid int32 // access via atomic
}
func Initialize(content DrawableInteractiveBeeper) (*UI, error) {
screen, err := tcell.NewScreen()
if err != nil {
return nil, err
}
if err = screen.Init(); err != nil {
return nil, err
}
screen.Clear()
screen.HideCursor()
width, height := screen.Size()
state := UI{
Content: content,
screen: screen,
tcEvents: make(chan tcell.Event, 10),
}
state.ctx = NewContext(width, height, screen, state.onPopover)
state.exit.Store(false)
go func() {
for !state.ShouldExit() {
state.tcEvents <- screen.PollEvent()
}
}()
state.invalid = 1
content.OnInvalidate(func(_ Drawable) {
atomic.StoreInt32(&state.invalid, 1)
})
content.OnBeep(screen.Beep)
content.Focus(true)
return &state, nil
}
func (state *UI) onPopover(p *Popover) {
state.popover = p
}
func (state *UI) ShouldExit() bool {
return state.exit.Load().(bool)
}
func (state *UI) Exit() {
state.exit.Store(true)
}
func (state *UI) Close() {
state.screen.Fini()
}
func (state *UI) Tick() bool {
more := false
select {
case event := <-state.tcEvents:
switch event := event.(type) {
case *tcell.EventResize:
state.screen.Clear()
width, height := event.Size()
state.ctx = NewContext(width, height, state.screen, state.onPopover)
state.Content.Invalidate()
}
// if we have a popover, and it can handle the event, it does so
if state.popover == nil || !state.popover.Event(event) {
// otherwise, we send the event to the main content
state.Content.Event(event)
}
more = true
default:
}
wasInvalid := atomic.SwapInt32(&state.invalid, 0)
if wasInvalid != 0 {
if state.popover != nil {
// if the previous frame had a popover, rerender the entire display
state.Content.Invalidate()
atomic.StoreInt32(&state.invalid, 0)
}
// reset popover for the next Draw
state.popover = nil
state.Content.Draw(state.ctx)
if state.popover != nil {
// if the Draw resulted in a popover, draw it
state.popover.Draw(state.ctx)
}
state.screen.Show()
more = true
}
return more
}
func (state *UI) EnableMouse() {
state.screen.EnableMouse()
}