installer: Rewrite welcome page.

The welcome page is the only page using absolute positioning for the newt
components, so that the page occupies all the screen space. This is becoming
too hard to manage, so switch to grid management like elsewhere, even if the
result is less appealing.

Also add an info text to the page with a mention on how to switch back to the
original installer.

* gnu/installer/newt/welcome.scm (run-menu-page): Use a vertically stacked
grid instead of hard window placement.

1 files changed, 27 insertions, 31 deletions

diff --git a/gnu/installer/newt/welcome.scm b/gnu/installer/newt/welcome.scm
index 8ed9f68918..3a0e45e198 100644
--- a/gnu/installer/newt/welcome.scm
+++ b/gnu/installer/newt/welcome.scm
@@ -26,20 +26,14 @@
   #:use-module (newt)
   #:export (run-welcome-page))
 
-;; Margin between screen border and newt root window.
-(define margin-left (make-parameter 3))
-(define margin-top (make-parameter 3))
-
 ;; Expected width and height for the logo.
-(define logo-width (make-parameter 50))
-(define logo-height (make-parameter 23))
+(define logo-width (make-parameter 43))
+(define logo-height (make-parameter 19))
 
-(define (nearest-exact-integer x)
-  "Given a real number X, return the nearest exact integer, with ties going to
-the nearest exact even integer."
-  (inexact->exact (round x)))
+(define info-textbox-width (make-parameter 70))
+(define options-listbox-height (make-parameter 5))
 
-(define* (run-menu-page title logo
+(define* (run-menu-page title info-text logo
                         #:key
                         listbox-items
                         listbox-item->text)
@@ -55,30 +49,27 @@ we want this page to occupy all the screen space available."
              (cons key item)))
          items))
 
-  (let* ((windows
-          (make-window (margin-left)
-                       (margin-top)
-                       (- (screen-columns) (* 2 (margin-left)))
-                       (- (screen-rows) (* 2 (margin-top)))
-                       title))
-         (logo-textbox
-          (make-textbox (nearest-exact-integer
-                         (- (/ (screen-columns) 2)
-                            (+ (/ (logo-width) 2) (margin-left))))
-                        (margin-top) (logo-width) (logo-height) 0))
-         (text (set-textbox-text logo-textbox
-                                 (read-all logo)))
+  (let* ((logo-textbox
+          (make-textbox -1 -1 (logo-width) (logo-height) 0))
+         (info-textbox
+          (make-reflowed-textbox -1 -1
+                                 info-text
+                                 (info-textbox-width)))
          (options-listbox
-          (make-listbox (margin-left)
-                        (+ (logo-height) (margin-top))
-                        (- (screen-rows) (+ (logo-height)
-                                            (* (margin-top) 4)))
+          (make-listbox -1 -1
+                        (options-listbox-height)
                         (logior FLAG-BORDER FLAG-RETURNEXIT)))
          (keys (fill-listbox options-listbox listbox-items))
+         (grid (vertically-stacked-grid
+                GRID-ELEMENT-COMPONENT logo-textbox
+                GRID-ELEMENT-COMPONENT info-textbox
+                GRID-ELEMENT-COMPONENT options-listbox))
          (form (make-form)))
-    (set-listbox-width options-listbox (- (screen-columns)
-                                          (* (margin-left) 4)))
-    (add-components-to-form form logo-textbox options-listbox)
+
+    (set-textbox-text logo-textbox (read-all logo))
+
+    (add-form-to-grid grid form #t)
+    (make-wrapped-grid-window grid title)
 
     (receive (exit-reason argument)
         (run-form form)
@@ -102,6 +93,11 @@ the page. Ask the user to choose between manual installation, graphical
 installation and reboot."
   (run-menu-page
    (G_ "GNU GuixSD install")
+   (G_ "Welcome to GNU GuixSD installer!
+
+Please note that the present graphical installer is still under heavy \
+development, so you might want to fallback to the classical installer by \
+pressing CTRL-ALT-F3.")
    logo
    #:listbox-items
    `((,(G_ "Install using the unguided shell based process")