ran-proc/pkgtest/run-group-test-2023-0125-0410/ui.go

package main

import (
	"context"
	"fmt"
	"github.com/gdamore/tcell/v2"
	"github.com/oklog/run"
	"github.com/rivo/tview"
	"io"
)

type UI struct {
	app    *tview.Application
	flex   *tview.Flex
	logbox *tview.TextView
	menu   *tview.List

	running bool
	grp     *run.Group
	pctx    context.Context
	cncl    context.CancelFunc
	tasks   []*Task
	logwr   io.Writer
}

func NewUI() *UI {
	ui := &UI{
		app:    tview.NewApplication(),
		flex:   tview.NewFlex(),
		logbox: tview.NewTextView(),
		menu:   tview.NewList(),
	}
	ui.flex.AddItem(ui.menu, 32, 0, true)
	ui.flex.AddItem(ui.logbox, 0, 1, false)
	ui.flex.SetDirection(tview.FlexColumn)
	ui.logbox.SetScrollable(true)
	ui.logbox.SetBackgroundColor(tcell.ColorNavy)
	ui.logwr = tview.ANSIWriter(ui.logbox)
	ui.menu.AddItem("start", "", 0, ui.startTasks)
	ui.menu.AddItem("cancel parent", "", 0, ui.killParent)
	ui.menu.AddItem("cancel Task1", "", 0, func() {
		ui.killTask(0)
	})
	ui.menu.AddItem("cancel Task2", "", 0, func() {
		ui.killTask(1)
	})
	ui.menu.AddItem("cancel Task3", "", 0, func() {
		ui.killTask(2)
	})

	ui.app.SetRoot(ui.flex, true)
	ui.app.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
		switch event.Key() {
		case tcell.KeyF1:
			{
				ui.app.SetFocus(ui.menu)
				break
			}
		case tcell.KeyF2:
			{
				ui.app.SetFocus(ui.logbox)
				break
			}
		default:
			{
				return event
			}
		}
		return nil
	})
	return ui
}

func (u *UI) killParent() {
	if u.running {
		_, _ = fmt.Fprintln(u, "[UI] cancel parent")
		u.cncl()
	} else {
		_, _ = fmt.Fprintln(u, "[UI] tasks not running")
	}
}

func (u *UI) startTasks() {
	if !u.running {
		u.grp = &run.Group{}
		ctx, cncl := context.WithCancel(context.Background())
		u.pctx = ctx
		u.cncl = cncl

		u.tasks = make([]*Task, 3)
		for i := 0; i < 3; i++ {
			t := NewTask(i+1, u.pctx, u)
			u.tasks[i] = t
			u.grp.Add(t.Task, t.Cancel)
		}
		go func() {
			_, _ = fmt.Fprintln(u, "[UI] run tasks.")
			u.running = true
			err := u.grp.Run()
			if err != nil {
				_, _ = fmt.Fprintln(u, "[UI] all tasks end, with error:", err)
			} else {
				_, _ = fmt.Fprintln(u, "[UI] all tasks end, with no error")
			}
			u.running = false
		}()
	} else {
		_, _ = fmt.Fprintln(u, "[UI] tasks already running")
	}
}

func (u *UI) killTask(id int) {
	if !u.running {
		_, _ = fmt.Fprintln(u, "[UI] tasks not running")
		return
	}
	v := u.tasks[id]
	if v != nil {
		_, _ = fmt.Fprintf(u, "[UI] cancel task %d\n", id+1)
		v.Cancel(nil)
	}
}

func (u *UI) Write(p []byte) (n int, err error) {
	return u.logwr.Write(p)
}

func (u *UI) Run() error {
	return u.app.Run()
}