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package main
// A simple program that counts down from 5 and then exits.
import (
"fmt"
"log"
"os"
"time"
tea "github.com/charmbracelet/bubbletea"
)
func main() {
// Log to a file. Useful in debugging since you can't really log to stdout.
// Not required.
logfilePath := os.Getenv("BUBBLETEA_LOG")
if logfilePath != "" {
if _, err := tea.LogToFile(logfilePath, "simple"); err != nil {
log.Fatal(err)
}
}
// Initialize our program
p := tea.NewProgram(model(5))
if _, err := p.Run(); err != nil {
log.Fatal(err)
}
}
// A model can be more or less any type of data. It holds all the data for a
// program, so often it's a struct. For this simple example, however, all
// we'll need is a simple integer.
type model int
// Init optionally returns an initial command we should run. In this case we
// want to start the timer.
func (m model) Init() tea.Cmd {
return tick
}
// Update is called when messages are received. The idea is that you inspect the
// message and send back an updated model accordingly. You can also return
// a command, which is a function that performs I/O and returns a message.
func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
switch msg := msg.(type) {
case tea.KeyMsg:
switch msg.String() {
case "ctrl+c", "q":
return m, tea.Quit
case "ctrl+z":
return m, tea.Suspend
}
case tickMsg:
m--
if m <= 0 {
return m, tea.Quit
}
return m, tick
}
return m, nil
}
// View returns a string based on data in the model. That string which will be
// rendered to the terminal.
func (m model) View() string {
return fmt.Sprintf("Hi. This program will exit in %d seconds.\n\nTo quit sooner press ctrl-c, or press ctrl-z to suspend...\n", m)
}
// Messages are events that we respond to in our Update function. This
// particular one indicates that the timer has ticked.
type tickMsg time.Time
func tick() tea.Msg {
time.Sleep(time.Second)
return tickMsg{}
}
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