DocumentWidget: Limit scrolling to document size

1 files changed, 14 insertions, 6 deletions

diff --git a/src/ui/documentwidget.c b/src/ui/documentwidget.c
index 7fe30f1e..acfa9eac 100644
--- a/src/ui/documentwidget.c
+++ b/src/ui/documentwidget.c
@@ -177,6 +177,12 @@ static iBool processEvent_DocumentWidget_(iDocumentWidget *d, const SDL_Event *e
     }
     else if (ev->type == SDL_MOUSEWHEEL) {
         d->scrollY -= 3 * ev->wheel.y * lineHeight_Text(default_FontId);
+        if (d->scrollY < 0) d->scrollY = 0;
+        const int scrollMax =
+            size_GmDocument(d->doc).y - height_Rect(bounds_Widget(w)) + d->pageMargin * gap_UI;
+        if (scrollMax > 0) {
+            d->scrollY = iMin(d->scrollY, scrollMax);
+        }
         postRefresh_App();
         return iTrue;
     }
@@ -198,7 +204,7 @@ static void drawRun_DrawContext_(void *context, const iGmRun *run) {
     initRange_String(&text, run->text);
     iInt2 origin = addY_I2(d->bounds.pos, -d->widget->scrollY);
     drawString_Text(run->font, add_I2(run->bounds.pos, origin), run->color, &text);
-//    drawRect_Paint(&d->paint, moved_Rect(run->bounds, origin), red_ColorId);
+    drawRect_Paint(&d->paint, moved_Rect(run->bounds, origin), red_ColorId);
     deinit_String(&text);
 }
 
@@ -215,13 +221,15 @@ static void draw_DocumentWidget_(const iDocumentWidget *d) {
     }
     if (d->state != ready_DocumentState) return;
     iDrawContext ctx = {.widget = d, .bounds = bounds_Widget(w) };
-    shrink_Rect(&ctx.bounds, init1_I2(gap_UI * d->pageMargin));
+    const int margin = gap_UI * d->pageMargin;
+    shrink_Rect(&ctx.bounds, init1_I2(margin));
     init_Paint(&ctx.paint);
     drawRect_Paint(&ctx.paint, ctx.bounds, teal_ColorId);
-    render_GmDocument(d->doc,
-                      (iRangei){ d->scrollY, d->scrollY + height_Rect(ctx.bounds) },
-                      drawRun_DrawContext_,
-                      &ctx);
+    render_GmDocument(
+        d->doc,
+        (iRangei){ d->scrollY - margin, d->scrollY + height_Rect(ctx.bounds) + margin },
+        drawRun_DrawContext_,
+        &ctx);
 }
 
 iBeginDefineSubclass(DocumentWidget, Widget)