Add full scrollback copy mode and copy-all command

Copy mode previously only allowed selecting text within a single viewport.
Scrolling erased and redrawed the buffer, invalidating any active mark/region.

Two new capabilities:

- `ghostel-copy-all` (C-c M-w): Instantly copies the entire scrollback to the
  kill ring using the ghostty formatter API. No rendering needed.

- `ghostel-copy-mode-load-all` (C-c C-a in copy mode): Loads the full scrollback
  into the buffer as styled text. After loading, standard Emacs selection works
  across the entire history (C-x h, C-s, mark/region spanning any distance).
  Scroll commands switch to native Emacs scrolling in this mode.

Copy mode entry remains instant with no behavior change for quick selections.

Author: dakra

README.md

@@ -166,6 +166,7 @@ test "$INSIDE_EMACS" = 'ghostel'; and source "$EMACS_GHOSTEL_PATH/etc/ghostel.fi
 | `C-c C-d`   | Send EOF (C-d)                         |
 | `C-c C-\`   | Send quit (C-\)                        |
 | `C-c C-t`   | Enter copy mode                        |
+| `C-c M-w`   | Copy entire scrollback to kill ring    |
 | `C-y`       | Yank from kill ring (bracketed paste)  |
 | `M-y`       | Yank-pop (cycle through kill ring)     |
 | `C-c C-y`   | Paste from kill ring                   |
@@ -183,21 +184,26 @@ Keys listed in `ghostel-keymap-exceptions` (default: `C-c`, `C-x`, `C-u`,
 Enter with `C-c C-t`. Standard Emacs navigation works.
 Normal letter keys exit copy mode and send the key to the terminal.
 
-| Key           | Action                          |
-|---------------|---------------------------------|
-| `C-SPC`       | Set mark                        |
-| `M-w` / `C-w` | Copy selection and exit         |
-| `C-n` / `C-p` | Move line (scrolls at edges)    |
-| `M-v` / `C-v` | Scroll page up / down           |
-| `M-<` / `M->` | Jump to top / bottom of buffer  |
-| `C-c C-n`     | Jump to next prompt             |
-| `C-c C-p`     | Jump to previous prompt         |
-| `C-l`         | Recenter viewport               |
-| `C-c C-t`     | Exit without copying            |
-| `a`–`z`       | Exit and send key to terminal   |
+| Key           | Action                           |
+|---------------|----------------------------------|
+| `C-SPC`       | Set mark                         |
+| `M-w` / `C-w` | Copy selection and exit          |
+| `C-n` / `C-p` | Move line (scrolls at edges)     |
+| `M-v` / `C-v` | Scroll page up / down            |
+| `M-<` / `M->` | Jump to top / bottom of buffer   |
+| `C-c C-n`     | Jump to next prompt              |
+| `C-c C-p`     | Jump to previous prompt          |
+| `C-l`         | Recenter viewport                |
+| `C-c C-a`     | Load full scrollback into buffer |
+| `C-c C-t`     | Exit without copying             |
+| `a`–`z`       | Exit and send key to terminal    |
 
 Soft-wrapped newlines are automatically stripped from copied text.
 
+After `C-c C-a`, the entire scrollback history is loaded into the buffer
+as styled text. Standard Emacs commands work across the full content:
+`C-x h` to select all, `C-s` to search, mark/region spanning any distance.
+
 ## Features
 
 ### Terminal Emulation
@@ -329,6 +335,7 @@ individual faces with `M-x customize-face`.
 | `M-x ghostel-clear`            | Clear screen and scrollback                  |
 | `M-x ghostel-clear-scrollback` | Clear scrollback only                        |
 | `M-x ghostel-copy-mode`        | Enter copy mode                              |
+| `M-x ghostel-copy-all`         | Copy entire scrollback to kill ring          |
 | `M-x ghostel-paste`            | Paste from kill ring                         |
 | `M-x ghostel-send-next-key`    | Send next key literally                      |
 | `M-x ghostel-next-prompt`      | Jump to next shell prompt                    |

ghostel.el

@@ -340,9 +340,11 @@ Bump this only when the Elisp code requires a newer native module
 (declare-function ghostel--encode-key "ghostel-module")
 (declare-function ghostel--focus-event "ghostel-module")
 (declare-function ghostel--mode-enabled "ghostel-module")
+(declare-function ghostel--copy-all-text "ghostel-module")
 (declare-function ghostel--module-version "ghostel-module")
 (declare-function ghostel--mouse-event "ghostel-module")
 (declare-function ghostel--new "ghostel-module")
+(declare-function ghostel--redraw-full-scrollback "ghostel-module")
 (declare-function ghostel--redraw "ghostel-module" (term &optional full))
 (declare-function ghostel--scroll "ghostel-module")
 (declare-function ghostel--scroll-bottom "ghostel-module")
@@ -556,6 +558,9 @@ DIR is the module directory."
 (defvar-local ghostel--copy-mode-active nil
   "Non-nil when copy mode is active.")
 
+(defvar-local ghostel--copy-mode-full-buffer nil
+  "Non-nil when full scrollback has been loaded into the buffer in copy mode.")
+
 (defvar-local ghostel--process nil
   "The shell process.")
 
@@ -647,6 +652,7 @@ Used for prompt navigation and optional re-application after full redraws.")
     (define-key map (kbd "C-c C-\\")  #'ghostel-send-C-backslash)
     (define-key map (kbd "C-c C-d")   #'ghostel-send-C-d)
     (define-key map (kbd "C-c C-t")   #'ghostel-copy-mode)
+    (define-key map (kbd "C-c M-w")   #'ghostel-copy-all)
     (define-key map (kbd "C-c C-y")   #'ghostel-paste)
     (define-key map (kbd "C-c C-l")   #'ghostel-clear-scrollback)
     (define-key map (kbd "C-c C-q")   #'ghostel-send-next-key)
@@ -1004,89 +1010,107 @@ pasted using bracketed paste."
 (defun ghostel--scroll-up (&optional _event)
   "Scroll the terminal viewport up (into scrollback)."
   (interactive "e")
-  (when ghostel--term
-    (ghostel--scroll ghostel--term -3)
-    (if ghostel--copy-mode-active
-        (let ((inhibit-read-only t))
-          (ghostel--redraw ghostel--term ghostel-full-redraw))
-      (setq ghostel--force-next-redraw t)
-      (ghostel--invalidate))))
+  (if ghostel--copy-mode-full-buffer
+      (scroll-down 3)
+    (when ghostel--term
+      (ghostel--scroll ghostel--term -3)
+      (if ghostel--copy-mode-active
+          (let ((inhibit-read-only t))
+            (ghostel--redraw ghostel--term ghostel-full-redraw))
+        (setq ghostel--force-next-redraw t)
+        (ghostel--invalidate)))))
 
 (defun ghostel--scroll-down (&optional _event)
   "Scroll the terminal viewport down."
   (interactive "e")
-  (when ghostel--term
-    (ghostel--scroll ghostel--term 3)
-    (if ghostel--copy-mode-active
-        (let ((inhibit-read-only t))
-          (ghostel--redraw ghostel--term ghostel-full-redraw))
-      (setq ghostel--force-next-redraw t)
-      (ghostel--invalidate))))
+  (if ghostel--copy-mode-full-buffer
+      (scroll-up 3)
+    (when ghostel--term
+      (ghostel--scroll ghostel--term 3)
+      (if ghostel--copy-mode-active
+          (let ((inhibit-read-only t))
+            (ghostel--redraw ghostel--term ghostel-full-redraw))
+        (setq ghostel--force-next-redraw t)
+        (ghostel--invalidate)))))
 
 (defun ghostel-copy-mode-scroll-up ()
   "Scroll the terminal viewport up by a page in copy mode."
   (interactive)
-  (when ghostel--term
-    (let ((height (count-lines (point-min) (point-max))))
-      (ghostel--scroll ghostel--term (- 2 height))
-      (let ((inhibit-read-only t))
-        (ghostel--redraw ghostel--term ghostel-full-redraw)))))
+  (if ghostel--copy-mode-full-buffer
+      (scroll-down-command)
+    (when ghostel--term
+      (let ((height (count-lines (point-min) (point-max))))
+        (ghostel--scroll ghostel--term (- 2 height))
+        (let ((inhibit-read-only t))
+          (ghostel--redraw ghostel--term ghostel-full-redraw))))))
 
 (defun ghostel-copy-mode-scroll-down ()
   "Scroll the terminal viewport down by a page in copy mode."
   (interactive)
-  (when ghostel--term
-    (let ((height (count-lines (point-min) (point-max))))
-      (ghostel--scroll ghostel--term (- height 2))
-      (let ((inhibit-read-only t))
-        (ghostel--redraw ghostel--term ghostel-full-redraw)))))
+  (if ghostel--copy-mode-full-buffer
+      (scroll-up-command)
+    (when ghostel--term
+      (let ((height (count-lines (point-min) (point-max))))
+        (ghostel--scroll ghostel--term (- height 2))
+        (let ((inhibit-read-only t))
+          (ghostel--redraw ghostel--term ghostel-full-redraw))))))
 
 (defun ghostel-copy-mode-previous-line ()
   "Move to the previous line, scrolling the viewport if at the top."
   (interactive)
   (let ((col (current-column)))
-    (if (= (line-number-at-pos) 1)
-        (when ghostel--term
-          (ghostel--scroll ghostel--term -1)
-          (let ((inhibit-read-only t))
-            (ghostel--redraw ghostel--term ghostel-full-redraw))
-          (goto-char (point-min)))
-      (forward-line -1))
+    (if ghostel--copy-mode-full-buffer
+        (forward-line -1)
+      (if (= (line-number-at-pos) 1)
+          (when ghostel--term
+            (ghostel--scroll ghostel--term -1)
+            (let ((inhibit-read-only t))
+              (ghostel--redraw ghostel--term ghostel-full-redraw))
+            (goto-char (point-min)))
+        (forward-line -1)))
     (move-to-column col)))
 
 (defun ghostel-copy-mode-next-line ()
   "Move to the next line, scrolling the viewport if at the bottom."
   (interactive)
   (let ((col (current-column)))
-    (if (>= (line-number-at-pos) (line-number-at-pos (point-max)))
-        (when ghostel--term
-          (ghostel--scroll ghostel--term 1)
-          (let ((inhibit-read-only t))
-            (ghostel--redraw ghostel--term ghostel-full-redraw))
-          (goto-char (point-max))
-          (beginning-of-line))
-      (forward-line 1))
+    (if ghostel--copy-mode-full-buffer
+        (forward-line 1)
+      (if (>= (line-number-at-pos) (line-number-at-pos (point-max)))
+          (when ghostel--term
+            (ghostel--scroll ghostel--term 1)
+            (let ((inhibit-read-only t))
+              (ghostel--redraw ghostel--term ghostel-full-redraw))
+            (goto-char (point-max))
+            (beginning-of-line))
+        (forward-line 1)))
     (move-to-column col)))
 
 (defun ghostel-copy-mode-beginning-of-buffer ()
   "Scroll to the top of scrollback in copy mode."
   (interactive)
-  (when ghostel--term
-    (ghostel--scroll-top ghostel--term)
-    (let ((inhibit-read-only t))
-      (ghostel--redraw ghostel--term ghostel-full-redraw))
-    (goto-char (point-min))))
+  (if ghostel--copy-mode-full-buffer
+      (goto-char (point-min))
+    (when ghostel--term
+      (ghostel--scroll-top ghostel--term)
+      (let ((inhibit-read-only t))
+        (ghostel--redraw ghostel--term ghostel-full-redraw))
+      (goto-char (point-min)))))
 
 (defun ghostel-copy-mode-end-of-buffer ()
   "Scroll to the bottom of scrollback in copy mode."
   (interactive)
-  (when ghostel--term
-    (ghostel--scroll-bottom ghostel--term)
-    (let ((inhibit-read-only t))
-      (ghostel--redraw ghostel--term ghostel-full-redraw))
-    ;; The native redraw already positions point at the terminal cursor,
-    ;; so no explicit goto-char needed here.
-    ))
+  (if ghostel--copy-mode-full-buffer
+      (progn
+        (goto-char (point-max))
+        (skip-chars-backward " \t\n"))
+    (when ghostel--term
+      (ghostel--scroll-bottom ghostel--term)
+      (let ((inhibit-read-only t))
+        (ghostel--redraw ghostel--term ghostel-full-redraw))
+      ;; The native redraw already positions point at the terminal cursor,
+      ;; so no explicit goto-char needed here.
+      )))
 
 (defun ghostel-copy-mode-end-of-line ()
   "Move to the last non-whitespace character on the line."
@@ -1100,30 +1124,32 @@ Scrolls the terminal viewport so the current line is vertically
 centered, then redraws.  When the scroll is clamped at a scrollback
 boundary (nothing to scroll into), does nothing."
   (interactive)
-  (when ghostel--term
-    (let* ((current-line (line-number-at-pos))
-           (win-height (window-body-height))
-           (center (/ win-height 2))
-           (col (current-column)))
-      (unless (= current-line center)
-        ;; Hash the buffer to detect whether the scroll was clamped.
-        (let ((old-hash (buffer-hash)))
-          (ghostel--scroll ghostel--term (- current-line center))
-          (let ((inhibit-read-only t))
-            (ghostel--redraw ghostel--term ghostel-full-redraw))
-          ;; If the buffer changed the viewport actually moved —
-          ;; reposition point at center.  Otherwise the scroll was
-          ;; clamped; restore point since redraw moved it to the
-          ;; terminal cursor.
-          (if (equal old-hash (buffer-hash))
-              (progn
-                (goto-char (point-min))
-                (forward-line (1- current-line))
-                (move-to-column col))
-            (goto-char (point-min))
-            (forward-line (1- (min center (line-number-at-pos (point-max)))))
-            (move-to-column col)
-            (recenter)))))))
+  (if ghostel--copy-mode-full-buffer
+      (recenter)
+    (when ghostel--term
+      (let* ((current-line (line-number-at-pos))
+             (win-height (window-body-height))
+             (center (/ win-height 2))
+             (col (current-column)))
+        (unless (= current-line center)
+          ;; Hash the buffer to detect whether the scroll was clamped.
+          (let ((old-hash (buffer-hash)))
+            (ghostel--scroll ghostel--term (- current-line center))
+            (let ((inhibit-read-only t))
+              (ghostel--redraw ghostel--term ghostel-full-redraw))
+            ;; If the buffer changed the viewport actually moved —
+            ;; reposition point at center.  Otherwise the scroll was
+            ;; clamped; restore point since redraw moved it to the
+            ;; terminal cursor.
+            (if (equal old-hash (buffer-hash))
+                (progn
+                  (goto-char (point-min))
+                  (forward-line (1- current-line))
+                  (move-to-column col))
+              (goto-char (point-min))
+              (forward-line (1- (min center (line-number-at-pos (point-max)))))
+              (move-to-column col)
+              (recenter))))))))
 
 
 ;;; Mouse input
@@ -1214,6 +1240,7 @@ boundary (nothing to scroll into), does nothing."
     (define-key map (kbd "M->")             #'ghostel-copy-mode-end-of-buffer)
     (define-key map (kbd "C-e")             #'ghostel-copy-mode-end-of-line)
     (define-key map (kbd "C-l")             #'ghostel-copy-mode-recenter)
+    (define-key map (kbd "C-c C-a")         #'ghostel-copy-mode-load-all)
     map)
   "Keymap for `ghostel-copy-mode'.
 Standard Emacs navigation works.
@@ -1259,19 +1286,26 @@ Press \\`q' or \\[ghostel-copy-mode-exit] to exit without copying."
   "Exit copy mode and return to terminal mode."
   (interactive)
   (when ghostel--copy-mode-active
-    (setq ghostel--copy-mode-active nil)
-    (setq cursor-type ghostel--saved-cursor-type)
-    (deactivate-mark)
-    (use-local-map ghostel--saved-local-map)
-    (when ghostel--saved-hl-line-mode
-      (hl-line-mode -1))
-    (setq buffer-read-only nil)
-    (setq mode-line-process nil)
-    (force-mode-line-update)
-    (when ghostel--term
-      (ghostel--scroll-bottom ghostel--term))
-    (ghostel--invalidate)
-    (message "Copy mode exited")))
+    (let ((was-full ghostel--copy-mode-full-buffer))
+      (setq ghostel--copy-mode-active nil)
+      (setq ghostel--copy-mode-full-buffer nil)
+      (setq cursor-type ghostel--saved-cursor-type)
+      (deactivate-mark)
+      (use-local-map ghostel--saved-local-map)
+      (when ghostel--saved-hl-line-mode
+        (hl-line-mode -1))
+      (setq buffer-read-only nil)
+      (setq mode-line-process nil)
+      (force-mode-line-update)
+      (when ghostel--term
+        (ghostel--scroll-bottom ghostel--term)
+        (when was-full
+          ;; Erase stale full-scrollback content so normal redraw rebuilds
+          (let ((inhibit-read-only t))
+            (erase-buffer)
+            (ghostel--redraw ghostel--term t))))
+      (ghostel--invalidate)
+      (message "Copy mode exited"))))
 
 (defun ghostel-copy-mode-exit-and-send ()
   "Exit copy mode and send the key that triggered exit to the terminal."
@@ -1313,6 +1347,34 @@ stripped so the copied text matches the original terminal content."
       (message "Copied to kill ring")))
   (ghostel-copy-mode-exit))
 
+(defun ghostel-copy-mode-load-all ()
+  "Load the entire scrollback into the buffer for cross-viewport selection.
+After loading, standard Emacs navigation and selection work across
+the full scrollback history."
+  (interactive)
+  (when (and ghostel--copy-mode-active ghostel--term
+             (not ghostel--copy-mode-full-buffer))
+    (message "Loading scrollback...")
+    (let* ((saved-line (1- (line-number-at-pos))) ; 0-based line within viewport
+           (saved-col (current-column))
+           (inhibit-read-only t)
+           (viewport-line (ghostel--redraw-full-scrollback ghostel--term)))
+      (goto-char (point-min))
+      (forward-line (+ (1- viewport-line) saved-line))
+      (move-to-column saved-col)
+      (recenter saved-line))
+    (setq ghostel--copy-mode-full-buffer t)
+    (message "Scrollback loaded")))
+
+(defun ghostel-copy-all ()
+  "Copy the entire scrollback buffer to the kill ring."
+  (interactive)
+  (when ghostel--term
+    (let ((text (ghostel--copy-all-text ghostel--term)))
+      (when (and text (> (length text) 0))
+        (kill-new text)
+        (message "Copied %d characters to kill ring" (length text))))))
+
 
 ;;; Hyperlinks (OSC 8)