v0.1.4 tui uniform transparent background policy, tui example added

cmd/example-tui/main.go

@@ -0,0 +1,103 @@
+// fv — file voyager: an lf / midnight-commander / xxd hybrid.
+// Demo application for the terminal + tui + color packages.
+//
+// Layout:   [parent dir] [current dir list] [preview: info + text/hex/dir table]
+// Enter on a file opens a fullscreen hex viewer with byte cursor and search.
+//
+// Keys (browse): j/k/arrows move · h/l or ←/→ parent/enter · Enter open
+//
+//	gg/G top/bottom · PgUp/PgDn, Ctrl+D/U page · ~ home · . hidden · s sort
+//	/ live filter (Esc clears) · Space mark · a mark-all · u unmark
+//	y yank paths · r rename · m mkdir · D delete (confirm) · T theme
+//	? help · Ctrl+L redraw · q quit · Q quit + exec $SHELL in last dir
+//
+// Keys (hex):    hjkl/arrows · 0/$ row ends · g/G · PgUp/PgDn · Ctrl+D/U
+//
+//	/ search (hex bytes like "de ad" / "0xdead", or literal text) · n/N cycle
+//	Esc/q back
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"syscall"
+	"time"
+
+	"github.com/lixenwraith/terminal"
+)
+
+const tickInterval = 100 * time.Millisecond // 10 fps animation clock
+
+func main() {
+	term := terminal.New()
+
+	// Raw-mode safety net: restore the terminal before re-panicking.
+	defer func() {
+		if r := recover(); r != nil {
+			terminal.EmergencyReset(os.Stdout)
+			panic(r)
+		}
+	}()
+
+	if err := term.Init(); err != nil {
+		fmt.Fprintln(os.Stderr, "terminal init:", err)
+		os.Exit(1)
+	}
+	_ = term.SetMouseMode(terminal.MouseModeClick) // wheel + click select
+
+	start, err := os.Getwd()
+	if err != nil {
+		start = "/"
+	}
+	app := newApp(term, start)
+	if err := app.loadDir(start, ""); err != nil {
+		term.Fini()
+		fmt.Fprintln(os.Stderr, "read dir:", err)
+		os.Exit(1)
+	}
+
+	// Animation clock: the input reader never emits {EventKey, KeyNone}
+	// (unknown sequences are swallowed), so it is a collision-free
+	// synthetic tick marker through the MPSC event channel.
+	tickDone := make(chan struct{})
+	go func() {
+		t := time.NewTicker(tickInterval)
+		defer t.Stop()
+		for {
+			select {
+			case <-tickDone:
+				return
+			case <-t.C:
+				term.PostEvent(terminal.Event{Type: terminal.EventKey, Key: terminal.KeyNone})
+			}
+		}
+	}()
+
+	for !app.quit {
+		app.render()
+		app.handleEvent(term.PollEvent())
+	}
+	close(tickDone)
+	term.Fini()
+
+	// --- cd-on-exit -----------------------------------------------------
+	// A child cannot change the parent shell's cwd. Best scriptless
+	// approximation: chdir + exec a fresh $SHELL (Q). Plain quit (q)
+	// records the dir for optional shell-function integration.
+	last := app.br.cwd
+	_ = os.Chdir(last)
+	if dir, err := os.UserCacheDir(); err == nil {
+		_ = os.WriteFile(filepath.Join(dir, "fv_lastdir"), []byte(last+"\n"), 0o600)
+	}
+	if app.execShell {
+		sh := os.Getenv("SHELL")
+		if sh == "" {
+			sh = "/bin/sh"
+		}
+		if _, err := os.Stat(sh); err == nil {
+			_ = syscall.Exec(sh, []string{sh}, os.Environ()) // no return on success
+		}
+	}
+	fmt.Fprintln(os.Stderr, last)
+}