keyboard and mouse handling

1 files changed, 136 insertions, 0 deletions

diff --git a/tui/event.go b/tui/event.go
new file mode 100644
index 0000000..4d0a535
--- /dev/null
+++ b/tui/event.go
@@ -0,0 +1,136 @@
+package tui
+
+import (
+	"os"
+	"os/signal"
+	"zgo.at/termfo"
+	"zgo.at/termfo/keys"
+	"strings"
+	"strconv"
+	"bufio"
+	"syscall"
+	"sync"
+)
+
+type Event struct {
+	TextInput rune
+	Key keys.Key
+	Mouse struct {
+		Button int
+		Pressed bool
+		Released bool
+		X, Y int
+		Scroll int
+	}
+	Err error
+	Resize bool
+}
+
+var evChan chan Event
+var once sync.Once
+func Events() <-chan Event {
+	once.Do(func() {
+		evChan = make(chan Event, 2)
+
+		// buffer FindKeys
+		ch := make(chan termfo.Event, 16)
+		go func() {
+			r := bufio.NewReader(os.Stdin)
+			for e := range terminfo.FindKeys(r) {
+				ch <- e
+				if e.Err != nil {
+					return
+				}
+			}
+		}()
+
+		go func() {
+			for kev := range ch {
+				var ev Event
+				if kev.Err != nil {
+					ev.Err = kev.Err
+					evChan <- ev
+					return
+				}
+
+				noMods := kev.Key & (keys.Ctrl | keys.Alt) == 0
+				notSpecial := kev.Key.WithoutMods() < (1 << 32)
+				if noMods && notSpecial {
+					r := rune(kev.Key.WithoutMods())
+					if kev.Key & keys.Shift != 0 && r >= 'a' && r <= 'z' {
+						r -= 0x20
+					}
+					ev.TextInput = r
+				}
+
+				switch kev.Key {
+				case keys.Mouse:
+					if err := parseMouse(&ev, ch); err != nil {
+						ev.Err = err
+						evChan <- ev
+						return
+					}
+				default:
+					ev.Key = kev.Key
+				}
+
+				evChan <- ev
+			}
+		}()
+
+		sigs := make(chan os.Signal, 1)
+		signal.Notify(sigs, syscall.SIGWINCH)
+		go func() {
+			for _ = range sigs {
+				evChan <- Event {Resize: true}
+			}
+		}()
+	})
+
+	return evChan
+}
+
+func parseMouse(ev *Event, ch <-chan termfo.Event) error {
+	var (
+		arg strings.Builder
+		args []int
+		down bool
+	)
+	parse: for kev := range ch {
+		if kev.Err != nil {
+			return kev.Err
+		}
+		switch {
+		case kev.Key >= '0' && kev.Key <= '9':
+			arg.WriteRune(rune(kev.Key))
+		case kev.Key == ';':
+			i, _ := strconv.Atoi(arg.String())
+			args = append(args, i)
+			arg.Reset()
+		case kev.Key == 'm' | keys.Shift:
+			down = true
+			fallthrough
+		default:
+			i, _ := strconv.Atoi(arg.String())
+			args = append(args, i)
+			break parse
+		}
+	}
+	if len(args) != 3 {
+		return nil
+	}
+	ev.Mouse.X = args[1] - 1
+	ev.Mouse.Y = args[2] - 1
+	switch args[0] {
+	case 64:
+		ev.Mouse.Scroll = -1
+	case 65:
+		ev.Mouse.Scroll = 1
+	default:
+		ev.Mouse.Button = args[0]
+		ev.Mouse.Pressed = down
+		ev.Mouse.Released = !down
+	}
+
+	return nil
+}