Interactive demo with tab navigation

- Three tabs: Home, Components, Stats with different content
- Real keyboard input: arrow keys to switch tabs, q to quit
- CSI escape sequence parsing for arrow keys
- Footer bar shows current tab position
- Tab bar highlights active tab in bright blue

demo.lisp

@@ -1,72 +1,155 @@
-;;; demo.lisp — cl-tty demo application
+;;; demo.lisp — cl-tty interactive demo
 ;;; Run: sbcl --script demo.lisp
 
 (load "~/quicklisp/setup.lisp")
 (ql:register-local-projects)
 (ql:quickload :cl-tty :silent t)
 
-;; ─── Demo ───────────────────────────────────────────────────────────────────
+;;; ─── Low-level input ───────────────────────────────────────────────────────
+
+(defun read-raw (&optional timeout)
+  (let ((fn (symbol-function (find-symbol "READ-RAW-BYTE" :cl-tty.input))))
+    (funcall fn :timeout (or timeout 10))))
+
+(defun read-key ()
+  (let ((b (read-raw)))
+    (unless b (return-from read-key nil))
+    (case b
+      (#x1b                                    ; ESC — could be Arrow, Escape, or Alt
+          (let ((b2 (read-raw 1)))
+          (unless b2 (return-from read-key :escape))
+          (if (= b2 #x5b)                      ; ESC [
+              (let ((b3 (read-raw 1)))
+                (case b3
+                  (#x41 :up)    (#x42 :down)
+                  (#x43 :right) (#x44 :left)
+                  (#x48 :home)  (#x46 :end)
+                  (#x5e                          ; ESC [ N ~
+                    (let ((b4 (read-raw 1)))
+                      (case b4
+                        (#x31 :home) (#x34 :end)
+                        (#x35 :page-up) (#x36 :page-down)
+                        (t :unknown))))
+                  (t :unknown)))
+              (t :unknown))))
+      (#x03 :ctrl-c)
+      (#x0d :enter)
+      (#x09 :tab)
+      (#x7f :backspace)
+      (t (code-char b)))))                     ; printable
+
+;;; ─── Tab content renderers ─────────────────────────────────────────────────
+
+(defun render-home (be)
+  (cl-tty.backend:draw-border be 6 7 68 10 :style :single :title " Welcome ")
+  (cl-tty.backend:draw-text be 8  9 "cl-tty — Pure CL terminal UI framework"
+                            :bright-white :default :bold t)
+  (cl-tty.backend:draw-text be 8 11 "  - 11 versions, 12 components"
+                            :white :default)
+  (cl-tty.backend:draw-text be 8 12 "  - No ncurses, no FFI, no external deps"
+                            :white :default)
+  (cl-tty.backend:draw-text be 8 13 "  - 280+ tests, 100% passing"
+                            :green :default)
+  (cl-tty.backend:draw-text be 8 15 "Arrows: switch tabs   Enter/q: quit"
+                            :bright-cyan :default :bold t))
+
+(defun render-components (be)
+  (cl-tty.backend:draw-border be 6 7 68 12 :style :single :title " Components ")
+  (loop for i from 0 below 6
+        for pair = (nth i '(("Box"        "Bordered containers, title, bg")
+                           ("Text"        "Styled text, word-wrap, spans")
+                           ("ScrollBox"   "Scrollable viewport, scrollbars")
+                           ("TabBar"      "Tab navigation — you're using it!")
+                           ("Select"      "Dropdown with fuzzy filter")
+                           ("Dialog"      "Modal overlays + Toast notifs")))
+        do (cl-tty.backend:draw-text be 8 (+ 9 i) (first pair)
+                                     :bright-yellow :default :bold t)
+           (cl-tty.backend:draw-text be 24 (+ 9 i) (second pair)
+                                     :white :default)))
+
+(defun render-stats (be)
+  (cl-tty.backend:draw-border be 6 7 68 10 :style :single :title " Stats ")
+  (cl-tty.backend:draw-text be 8  9 "Metric"     :bright-white :default :bold t)
+  (cl-tty.backend:draw-text be 40 9 "Value"      :bright-white :default :bold t)
+  (loop for i from 0 below 8
+        for pair = (nth i '(("Versions"     "11")
+                           ("Components"   "12")
+                           ("Tests"        "280+")
+                           ("Lines"        "~3060")
+                           ("Dependencies" "0")
+                           ("FFI"          "0")
+                           ("ncurses"      "no")
+                           ("License"      "TBD")))
+        do (cl-tty.backend:draw-text be 8  (+ 11 i) (first pair)
+                                     :white :default)
+           (cl-tty.backend:draw-text be 40 (+ 11 i) (second pair)
+                                     :bright-green :default :bold t)))
+
+;;; ─── Tab bar ───────────────────────────────────────────────────────────────
+
+(defun render-tabs (be tabs active)
+  (let ((x 8))
+    (cl-tty.backend:draw-rect be 6 4 68 1 :bg :default)
+    (loop for label in tabs for i from 0
+          do (let* ((text (format nil " ~a " label)) (len (length text)))
+               (if (= i active)
+                   (progn (cl-tty.backend:draw-rect be x 4 len 1 :bg :bright-blue)
+                          (cl-tty.backend:draw-text be x 4 text
+                                                    :bright-white :bright-blue :bold t))
+                   (cl-tty.backend:draw-text be x 4 text :bright-white :default))
+               (incf x (+ len 2))))))
+
+;;; ─── Main loop ─────────────────────────────────────────────────────────────
 
 (defun run-demo ()
-  (let ((backend (make-instance 'cl-tty.backend:modern-backend))
+  (let* ((be (make-instance 'cl-tty.backend:modern-backend))
-        (read-fn (symbol-function (find-symbol "READ-RAW-BYTE" :cl-tty.input))))
+         (tabs '(" Home " " Components " " Stats "))
-    ;; Initialize
+         (active 0)
-    (cl-tty.backend:initialize-backend backend)
+         (running t))
-    (cl-tty.backend:backend-clear backend)
-    (cl-tty.backend:cursor-hide backend)
 
-    ;; Title box
+    (cl-tty.backend:initialize-backend be)
-    (cl-tty.backend:draw-border backend 1 1 78 3 :style :double :title " cl-tty Demo ")
+    (cl-tty.backend:cursor-hide be)
-    (cl-tty.backend:draw-text backend 3 2
-      "A pure-CL terminal UI framework. No ncurses, no FFI."
-      :white :default :bold t)
 
-    ;; Components grid
+    (loop while running
-    (cl-tty.backend:draw-border backend 1 5 78 12 :style :single :title " Components ")
+          do (cl-tty.backend:backend-clear be)
-    (loop for i from 0 below 5
-          for item = (nth i '((" Box                  Bordered containers with title and background"
-                               " Text                 Styled text with word-wrap and spans")
-                              (" ScrollBox            Scrollable viewport with scrollbars"
-                               " TabBar               Horizontal tab navigation")
-                              (" Select               Dropdown with fuzzy filter"
-                               " TextInput / TextArea  Single/multi-line input with undo")
-                              (" Markdown             Renders markdown with syntax highlighting"
-                               " Dialog / Toast       Modal overlays and notifications")
-                              (" Mouse                Event handlers and text selection"
-                               " Slot System          Named slots for extensible UI")))
-          do (cl-tty.backend:draw-text backend 3 (+ 7 i) (first item) :white :default)
-             (cl-tty.backend:draw-text backend 42 (+ 7 i) (second item) :white :default))
 
-    ;; Backend features table
+             ;; Title
-    (cl-tty.backend:draw-border backend 1 18 78 5 :style :single :title " Backend Support ")
+             (cl-tty.backend:draw-border be 2 1 76 3 :style :double :title " cl-tty ")
-    (cl-tty.backend:draw-text backend 3 20 "Feature" :bright-white :default :bold t)
+             (cl-tty.backend:draw-text be 4 2
-    (cl-tty.backend:draw-text backend 25 20 "modern" :bright-white :default :bold t)
+               "Interactive demo — navigate with arrows, q to quit"
-    (cl-tty.backend:draw-text backend 40 20 "simple" :bright-white :default :bold t)
+               :bright-white :default)
-    (cl-tty.backend:draw-text backend 3 21 "Truecolor (24-bit)" :white :default)
-    (cl-tty.backend:draw-text backend 25 21 "yes" :green :default)
-    (cl-tty.backend:draw-text backend 40 21 "no" :red :default)
-    (cl-tty.backend:draw-text backend 3 22 "OSC 8 hyperlinks" :white :default)
-    (cl-tty.backend:draw-text backend 25 22 "yes" :green :default)
-    (cl-tty.backend:draw-text backend 40 22 "no" :red :default)
 
-    ;; Footer bar
+             ;; Tabs + content
-    (cl-tty.backend:draw-rect backend 1 24 78 1 :bg :blue)
+             (render-tabs be tabs active)
-    (cl-tty.backend:draw-text backend 2 24 " Press q to quit " :bright-white :blue :bold t)
+             (case active
+               (0 (render-home be))
+               (1 (render-components be))
+               (2 (render-stats be)))
 
-    (cl-tty.backend:cursor-show backend)
+             ;; Footer
+             (cl-tty.backend:draw-rect be 2 23 76 1 :bg :blue)
+             (cl-tty.backend:draw-text be 2 23
+               (format nil " Tab ~d/3: ~a "
+                       (1+ active) (string-trim " " (nth active tabs)))
+               :bright-white :blue :bold t)
 
-    ;; Wait for q keypress
+             ;; Input
-    (loop
+             (let ((key (read-key)))
-      (let ((ch (funcall read-fn :timeout 1)))
+               (case key
-        (when ch
+                 (:ctrl-c  (setf running nil))
-          (when (or (char= (code-char ch) #\q) (= ch 3))
+                 (:enter   (setf running nil))
-            (return)))))
+                 (#\q      (setf running nil))
+                 (#\Q      (setf running nil))
+                 (:right   (setf active (mod (1+ active) (length tabs))))
+                 (:left    (setf active (mod (1- active) (length tabs))))
+                 (:tab     (setf active (mod (1+ active) (length tabs)))))))
 
-    ;; Cleanup
+    (cl-tty.backend:cursor-show be)
-    (cl-tty.backend:backend-clear backend)
+    (cl-tty.backend:backend-clear be)
-    (cl-tty.backend:shutdown-backend backend)))
+    (cl-tty.backend:shutdown-backend be)))
 
-;; ─── Run ────────────────────────────────────────────────────────────────────
+;;; ─── Entry ──────────────────────────────────────────────────────────────────
 
-(when (probe-file "/dev/tty")
+(if (probe-file "/dev/tty")
-  (run-demo))
+    (run-demo)
+    (format t "No TTY detected. Run in a terminal for the interactive demo.~%"))