From bea482877e9c8774fad86b22bd065e213a80a3ba Mon Sep 17 00:00:00 2001
From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Tue, 5 Jan 2021 14:53:15 +0100
Subject: [PATCH] Re-implement display of MARGIN_RIGHT_ADDRESS_BOX

The correct way of implementing this is at paragraph level. Once this
is clear, the implementation is straightforward.

Note that RtL is not handled correctly by the \lyxrightaddress macro.

Fixes bug #11918 and #8152.
---
 src/TextMetrics.cpp | 66 +++++++++++++++++----------------------------
 1 file changed, 25 insertions(+), 41 deletions(-)

diff --git a/src/TextMetrics.cpp b/src/TextMetrics.cpp
index 89e8699077..0f2ef90b9d 100644
--- a/src/TextMetrics.cpp
+++ b/src/TextMetrics.cpp
@@ -557,6 +557,29 @@ bool TextMetrics::redoParagraph(pit_type const pit, bool const align_rows)
 	if (row_index < pm.rows().size())
 		pm.rows().resize(row_index);
 
+	// This type of margin can only be handled at the global paragraph level
+	if (par.layout().margintype == MARGIN_RIGHT_ADDRESS_BOX) {
+		int offset = 0;
+		if (par.isRTL(buffer.params())) {
+			// globally align the paragraph to the left.
+			int minleft = max_width_;
+			for (Row const & row : pm.rows())
+				minleft = min(minleft, row.left_margin);
+			offset = right_margin - minleft;
+		} else {
+			// globally align the paragraph to the right.
+			int maxwid = 0;
+			for (Row const & row : pm.rows())
+				maxwid = max(maxwid, row.width());
+			offset = max_width_ - right_margin - maxwid;
+		}
+
+		for (Row & row : pm.rows()) {
+			row.left_margin += offset;
+			row.dim().wid += offset;
+		}
+	}
+
 	// The space above and below the paragraph.
 	int const top = parTopSpacing(pit);
 	pm.rows().front().dim().asc += top;
@@ -779,22 +802,6 @@ int TextMetrics::labelFill(Row const & row) const
 }
 
 
-#if 0
-// Not used, see TextMetrics::breakRow
-// this needs special handling - only newlines count as a break point
-static pos_type addressBreakPoint(pos_type i, Paragraph const & par)
-{
-	pos_type const end = par.size();
-
-	for (; i < end; ++i)
-		if (par.isNewline(i))
-			return i + 1;
-
-	return end;
-}
-#endif
-
-
 int TextMetrics::labelEnd(pit_type const pit) const
 {
 	// labelEnd is only needed if the layout fills a flushleft label.
@@ -886,14 +893,6 @@ bool TextMetrics::breakRow(Row & row, int const right_margin) const
 	// the width available for the row.
 	int const width = max_width_ - row.right_margin;
 
-#if 0
-	//FIXME: As long as leftMargin() is not correctly implemented for
-	// MARGIN_RIGHT_ADDRESS_BOX, we should also not do this here.
-	// Otherwise, long rows will be painted off the screen.
-	if (par.layout().margintype == MARGIN_RIGHT_ADDRESS_BOX)
-		return addressBreakPoint(pos, par);
-#endif
-
 	// check for possible inline completion
 	DocIterator const & ic_it = bv_->inlineCompletionPos();
 	pos_type ic_pos = -1;
@@ -1729,25 +1728,10 @@ int TextMetrics::leftMargin(pit_type const pit, pos_type const pos) const
 		}
 		break;
 
-	case MARGIN_RIGHT_ADDRESS_BOX: {
-#if 0
-		// The left margin depends on the widest row in this paragraph.
-		// This code is wrong because it depends on the rows, but at the
-		// same time this function is used in redoParagraph to construct
-		// the rows.
-		ParagraphMetrics const & pm = par_metrics_[pit];
-		int minfill = max_width_;
-		for (row : pm.rows())
-			if (row.fill() < minfill)
-				minfill = row.fill();
-		l_margin += bfm.signedWidth(layout.leftmargin);
-		l_margin += minfill;
-#endif
-		// also wrong, but much shorter.
-		l_margin += max_width_ / 2;
+	case MARGIN_RIGHT_ADDRESS_BOX:
+		// This is handled globally in redoParagraph().
 		break;
 	}
-	}
 
 	if (!par.params().leftIndent().zero())
 		l_margin += par.params().leftIndent().inPixels(max_width_, lfm.em());
-- 
2.39.2