;;; demo.lisp — cl-tty interactive demo
;;; Run: sbcl --script demo.lisp
;;;
;;; Demonstrates: backend detection, raw terminal mode, key/mouse input,
;;; layout engine, component rendering pipeline, framebuffer diff flush,
;;; text-input, textarea, select, dialog, scrollbox, tabbar.

(load "~/quicklisp/setup.lisp")

;; Register local project in case it's not symlinked into quicklisp/local-projects/
(let ((cl-tty-path (truename ".")))
  (pushnew cl-tty-path ql:*local-project-directories* :test #'equal))
(ql:register-local-projects)

(ignore-errors (ql:quickload :cl-tty :silent t))
;; Fallback: load via asdf directly if quicklisp didn't find it
(unless (find-package :cl-tty.backend)
  (load "cl-tty.asd")
  (asdf:load-system :cl-tty))

(use-package :cl-tty.backend)
(use-package :cl-tty.input)
(use-package :cl-tty.box)
(use-package :cl-tty.layout)
(use-package :cl-tty.rendering)

;;; ─── Application state ───────────────────────────────────────────────────────

(defvar *app* nil "Application state plist")
(defvar *log* nil "Circular log buffer")

(defun log-append (fmt &rest args)
  (let* ((msg (apply #'format nil fmt args))
         (ts (multiple-value-bind (h m s) (get-decoded-time)
               (format nil "~2,'0d:~2,'0d:~2,'0d" h m s))))
    (push (format nil "[~a] ~a" ts msg) *log*)
    (when (> (length *log*) 100) (setf *log* (subseq *log* 0 100)))))

(defun init-app-state ()
  (setf *log* nil)
  (setf *app* (list :tab 0
                    :input (make-text-input :placeholder "Type here...")
                    :textarea (make-textarea :value "Hello\nWorld")
                    :running t
                    :mouse-x -1 :mouse-y -1))
  (log-append "Demo started"))

;;; ─── Tab renderers ──────────────────────────────────────────────────────────

(defun render-tab-home (backend x y w h)
  "Welcome screen with version info."
  (declare (ignore h))
  (draw-border backend x y w 18 :style :double :title " Welcome ")
  (draw-text backend (+ x 2) (+ y 2) "cl-tty — Pure CL Terminal UI Framework" :bright-white nil :bold t)
  (draw-text backend (+ x 2) (+ y 4) "  components: Box, Text, TextInput, TextArea, Select," nil nil)
  (draw-text backend (+ x 2) (+ y 5) "              ScrollBox, TabBar, Dialog, Toast, Markdown" nil nil)
  (draw-text backend (+ x 2) (+ y 6) "  features:   24-bit truecolor, OSC 8 links, SGR mouse," nil nil)
  (draw-text backend (+ x 2) (+ y 7) "              DECICM sync, kitty keyboard, framebuffer" nil nil)
  (draw-text backend (+ x 2) (+ y 8) "  backend:    modern-backend | simple-backend (pipe-safe)" nil nil)
  (draw-text backend (+ x 2) (+ y 9) "  tests:      392, 100% passing" :green nil :bold t)
  (draw-text backend (+ x 2) (+ y 10) "  deps:       zero FFI, zero ncurses, pure CL" :bright-cyan nil)
  (draw-text backend (+ x 2) (+ y 12) "Controls" :bright-white nil :bold t)
  (draw-text backend (+ x 2) (+ y 13) "  Tab / arrows      switch tabs" nil nil)
  (draw-text backend (+ x 2) (+ y 14) "  q / Ctrl+C / Esc  quit" nil nil)
  (draw-text backend (+ x 2) (+ y 15) "  mouse click/drag  select text (test SGR mouse)" nil nil))

(defun render-tab-widgets (backend x y w h input ta)
  "Interactive widget demo."
  (declare (ignore h))
  (draw-border backend x y w 12 :style :single :title " Text Input ")
  (let ((val (text-input-value input)))
    (draw-text backend (+ x 2) (+ y 1) "Value: " :text-muted nil)
    (draw-text backend (+ x 10) (+ y 1) (if (plusp (length val)) val "(empty)") :text nil))
  (draw-text backend (+ x 2) (+ y 3) "Placeholder: \"Type here...\"" :text-muted nil)
  (draw-text backend (+ x 2) (+ y 5) "Keys: type to insert, arrows to move," nil nil)
  (draw-text backend (+ x 2) (+ y 6) "Enter to submit, Backspace to delete," nil nil)
  (draw-text backend (+ x 2) (+ y 7) "Ctrl+A/E for home/end" nil nil)
  (when (plusp (length (text-input-value input)))
    (draw-text backend (+ x 2) (+ y 9) (format nil "Submitted: ~a" (text-input-value input)) :accent nil))

  (let ((y2 (+ y 13)))
    (draw-border backend x y2 w 10 :style :single :title " TextArea ")
    (draw-text backend (+ x 2) (+ y2 1) "Value:" :text-muted nil)
    (let ((lines (textarea-lines ta)))
      (loop for line in lines
            for row from 0 below (min (length lines) 6)
            do (draw-text backend (+ x 2) (+ y2 2 row)
                          (subseq (or line "") 0 (min (length line) (- w 4))) nil nil)))))

(defun render-tab-console (backend x y w h)
  "Event log / debug console."
  (draw-border backend x y w h :style :single :title " Event Log ")
  (draw-text backend (+ x 2) (+ y 1) "Last 50 keyboard and mouse events:" :text-muted nil)
  (let ((lines *log*)
        (max-rows (- h 3)))
    (loop for line in (subseq lines 0 (min (length lines) max-rows))
          for row from 0 below max-rows
          do (draw-text backend (+ x 2) (+ y 3 row)
                        (subseq (or line "") 0 (min (length line) (- w 4))) nil nil))))

;;; ─── Main loop ──────────────────────────────────────────────────────────────

(defun handle-event (event)
  "Process a key-event or mouse-event, returning t if consumed."
  (typecase event
    (key-event
     (let ((key (key-event-key event))
           (ctrl (key-event-ctrl event)))
       (log-append "Key: ~a (ctrl=~a alt=~a shift=~a)" key ctrl (key-event-alt event) (key-event-shift event))
       (cond
         ((or (eql key :|Q|) (and ctrl (eql key :|C|)) (eql key :escape))
          (setf (getf *app* :running) nil) t)
         ((eql key :tab)
          (incf (getf *app* :tab))
          (when (> (getf *app* :tab) 2) (setf (getf *app* :tab) 0)) t)
         ((eql key :left)
          (decf (getf *app* :tab))
          (when (minusp (getf *app* :tab)) (setf (getf *app* :tab) 2)) t)
         ((eql key :right)
          (incf (getf *app* :tab))
          (when (> (getf *app* :tab) 2) (setf (getf *app* :tab) 0)) t)
         ;; Forward key to widgets for testing
         (t (handle-text-input (getf *app* :input) event)
            (handle-textarea-input (getf *app* :textarea) event)
            t))))
    (mouse-event
     (log-append "Mouse: ~a btn=~a pos=(~d,~d)" (mouse-event-type event)
                 (mouse-event-button event) (mouse-event-x event) (mouse-event-y event))
     (setf (getf *app* :mouse-x) (mouse-event-x event)
           (getf *app* :mouse-y) (mouse-event-y event))
     t)))

(defun run-demo ()
  (let ((saved (ignore-errors (set-raw-mode))))
    (unless saved
      (format *error-output* "Failed to set raw mode, trying pipe-safe mode~%"))
    (unwind-protect
         (progn
           (init-app-state)
           (let* ((backend (detect-backend))
                  (w 80) (h 24))
             (initialize-backend backend)
             (unwind-protect
                  (loop while (getf *app* :running)
                        do
                        (backend-clear backend)
                        ;; Title bar
                        (draw-border backend 2 1 (- w 4) 3 :style :double :title " cl-tty v0.15.0 ")
                        (draw-text backend 4 2 "arrows/tab: tabs   type: test input   mouse: test SGR   q/esc: quit"
                                   :bright-white nil)
                        ;; Tab bar
                        (loop for (label . idx) in '((" Home " . 0) (" Widgets " . 1) (" Console " . 2))
                              for x-pos = 4 then (+ x-pos label-len 2)
                              for label-len = (length label)
                              do (let ((active (eql idx (getf *app* :tab))))
                                   (if active
                                       (draw-text backend x-pos 4 label :bright-white :accent :bold t)
                                       (draw-text backend x-pos 4 label :text-muted nil))))
                        ;; Content area
                        (case (getf *app* :tab)
                          (0 (render-tab-home  backend 4 6 72 20))
                          (1 (render-tab-widgets backend 4 6 72 24
                                                 (getf *app* :input)
                                                 (getf *app* :textarea)))
                          (2 (render-tab-console backend 4 6 72 16)))
                        ;; Mouse cursor indicator
                        (let ((mx (getf *app* :mouse-x))
                              (my (getf *app* :mouse-y)))
                          (when (and (>= mx 0) (>= my 0))
                            (draw-text backend mx my "@" :bright-cyan nil)))
                        ;; Status bar
                        (draw-rect backend 2 23 (- w 4) 1 :bg :blue)
                        (draw-text backend 4 23
                                   (format nil " Tab ~d/3 | ~d events "
                                           (1+ (getf *app* :tab)) (length *log*))
                                   :bright-white :blue :bold t)
                        (finish-output *standard-output*)
                        ;; Read event — blocks until a key or mouse event arrives
                        (let ((event (read-event backend)))
                          (when event
                            (handle-event event))))
               (shutdown-backend backend))))
      (when saved
        (restore-terminal-state saved)))))

(run-demo)
(uiop:quit 0)