astro-domu/internal/ui/ui.go

package ui

import (
	"github.com/gdamore/tcell/v2"
	"github.com/jordanorelli/astro-domu/internal/exit"
	"github.com/jordanorelli/astro-domu/internal/wire"
	"github.com/jordanorelli/blammo"
)

type UI struct {
	*blammo.Log
	screen tcell.Screen
	mode   Mode
	client *wire.Client
}

func (ui *UI) Run() {
	ui.client = &wire.Client{
		Log:  ui.Child("client"),
		Host: "127.0.0.1",
		Port: 12805,
	}

	notifications, err := ui.client.Dial()
	if err != nil {
		exit.WithMessage(1, "unable to dial server: %v", err)
	}
	go ui.handleNotifications(notifications)

	screen, err := tcell.NewScreen()
	if err != nil {
		exit.WithMessage(1, "unable to create a screen: %v", err)
	}
	ui.screen = screen
	ui.Debug("sceen created")

	if err := screen.Init(); err != nil {
		exit.WithMessage(1, "unable to initialize screen: %v", err)
	}
	ui.Debug("screen initialized")
	width, height := screen.Size()
	ui.Debug("screen width: %d", width)
	ui.Debug("screen height: %d", height)
	ui.Debug("screen colors: %v", screen.Colors())
	ui.Debug("screen has mouse: %v", screen.HasMouse())

	ui.mode = &boxWalker{
		width:  10,
		height: 6,
	}
	ui.Info("running ui")
	if ui.run() {
		ui.Info("user requested close")
		ui.Info("closing client")
		ui.client.Close()
		ui.Info("client closed")
		ui.Info("finalizing screen")
	}
	ui.Info("run loop done, shutting down")
	screen.Fini()
}

func (ui *UI) handleNotifications(c <-chan wire.Response) {
	for n := range c {
		ui.Info("ignoring notification: %v", n)
	}
	ui.Info("notifications channel is closed so we must be done")
	ui.Info("clearing and finalizing screen from notifications goroutine")
	ui.screen.Clear()
	ui.screen.Fini()
}

// writeString writes a string in the given style from left to right beginning
// at the location (x, y). Writing of the screen just fails silently so don't
// do that.
func (ui *UI) writeString(x, y int, s string, style tcell.Style) {
	width, height := ui.screen.Size()
	if y > height {
		return
	}
	for i, r := range []rune(s) {
		x := x + i
		if x > width {
			return
		}
		ui.screen.SetContent(x, y, r, nil, style)
	}
}

func (ui *UI) run() bool {
	ui.screen.Clear()
	ui.mode.draw(ui)

	for {
		e := ui.screen.PollEvent()
		if e == nil {
			ui.Info("run loop sees nil event, breaking out")
			// someone else shut us down, so return false
			return false
		}

		switch v := e.(type) {
		case *tcell.EventKey:
			key := v.Key()
			if key == tcell.KeyCtrlC {
				ui.Info("saw ctrl+c keyboard input, shutting down")
				// we want to shut things down
				return true
			}
		}

		ui.mode.handleEvent(ui, e)
		ui.screen.Clear()
		ui.mode.draw(ui)
		ui.screen.Show()
	}
}