From 3854843cff3aaae10dd898602b05a78613937768 Mon Sep 17 00:00:00 2001
From: Milan Crha <mcrha@redhat.com>
Date: Wed, 2 Sep 2020 18:27:21 +0200
Subject: evo-I#461 - Let 'Wrap quoted text in replies' influence paragraph
 style

Related to https://gitlab.gnome.org/GNOME/evolution/-/issues/461
---
 src/camel/camel-enums.h              |  7 ++++-
 src/camel/camel-mime-filter-tohtml.c | 59 ++++++++++++++++++++++++++++++++++--
 2 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/src/camel/camel-enums.h b/src/camel/camel-enums.h
index df3c9a70f..659e9d877 100644
--- a/src/camel/camel-enums.h
+++ b/src/camel/camel-enums.h
@@ -168,6 +168,7 @@ typedef enum { /*< flags >*/
  * CamelMimeFilterToHTMLFlags:
  * @CAMEL_MIME_FILTER_TOHTML_PRE:
  *     Enclose the content in &lt;pre&gt; ... &lt;/pre&gt; tags.
+ *     Cannot be used together with %CAMEL_MIME_FILTER_TOHTML_DIV.
  * @CAMEL_MIME_FILTER_TOHTML_CONVERT_NL:
  *     Convert newline characters to &lt;br&gt; tags.
  * @CAMEL_MIME_FILTER_TOHTML_CONVERT_SPACES:
@@ -190,6 +191,9 @@ typedef enum { /*< flags >*/
  *     Group lines beginning with one or more '&gt;' characters in
  *     &lt;blockquote type="cite"&gt; ... &lt;/blockquote&gt; tags. The tags
  *     are nested according to the number of '&gt;' characters.
+ * @CAMEL_MIME_FILTER_TOHTML_DIV:
+ *     Enclose the paragraphs in &lt;div&gt; ... &lt;/div&gt; tags.
+ *     Cannot be used together with %CAMEL_MIME_FILTER_TOHTML_PRE.
  *
  * Flags for converting text/plain content into text/html.
  **/
@@ -204,7 +208,8 @@ typedef enum { /*< flags >*/
 	CAMEL_MIME_FILTER_TOHTML_CITE = 1 << 7,
 	CAMEL_MIME_FILTER_TOHTML_PRESERVE_8BIT = 1 << 8,
 	CAMEL_MIME_FILTER_TOHTML_FORMAT_FLOWED = 1 << 9,
-	CAMEL_MIME_FILTER_TOHTML_QUOTE_CITATION = 1 << 10
+	CAMEL_MIME_FILTER_TOHTML_QUOTE_CITATION = 1 << 10,
+	CAMEL_MIME_FILTER_TOHTML_DIV = 1 << 11
 } CamelMimeFilterToHTMLFlags;
 
 /**
diff --git a/src/camel/camel-mime-filter-tohtml.c b/src/camel/camel-mime-filter-tohtml.c
index 7fce56238..85254d271 100644
--- a/src/camel/camel-mime-filter-tohtml.c
+++ b/src/camel/camel-mime-filter-tohtml.c
@@ -37,6 +37,7 @@ struct _CamelMimeFilterToHTMLPrivate {
 
 	guint32 column : 31;
 	guint32 pre_open : 1;
+	gboolean div_open;
 };
 
 /*
@@ -277,7 +278,7 @@ html_convert (CamelMimeFilter *mime_filter,
 	priv = CAMEL_MIME_FILTER_TOHTML (mime_filter)->priv;
 
 	if (inlen == 0) {
-		if (!priv->pre_open && priv->blockquote_depth == 0) {
+		if (!priv->pre_open && !priv->div_open && !priv->blockquote_depth) {
 			/* No closing tags needed. */
 			*out = (gchar *) in;
 			*outlen = 0;
@@ -288,6 +289,12 @@ html_convert (CamelMimeFilter *mime_filter,
 		outptr = mime_filter->outbuf;
 		outend = mime_filter->outbuf + mime_filter->outsize;
 
+		if (priv->div_open) {
+			outptr = check_size (mime_filter, outptr, &outend, 7);
+			outptr = g_stpcpy (outptr, "</div>");
+			priv->div_open = FALSE;
+		}
+
 		while (priv->blockquote_depth > 0) {
 			outptr = check_size (mime_filter, outptr, &outend, 15);
 			outptr = g_stpcpy (outptr, "</blockquote>");
@@ -315,7 +322,7 @@ html_convert (CamelMimeFilter *mime_filter,
 	outptr = mime_filter->outbuf;
 	outend = mime_filter->outbuf + mime_filter->outsize;
 
-	if (priv->flags & CAMEL_MIME_FILTER_TOHTML_PRE && !priv->pre_open) {
+	if ((priv->flags & CAMEL_MIME_FILTER_TOHTML_PRE) != 0 && !priv->pre_open) {
 		outptr = check_size (mime_filter, outptr, &outend, 6);
 		outptr = g_stpcpy (outptr, "<pre>");
 		priv->pre_open = TRUE;
@@ -338,6 +345,12 @@ html_convert (CamelMimeFilter *mime_filter,
 			if (depth > 0) {
 				/* FIXME: we could easily support multiple color depths here */
 
+				if ((priv->flags & CAMEL_MIME_FILTER_TOHTML_DIV) != 0 && !priv->div_open) {
+					outptr = check_size (mime_filter, outptr, &outend, 6);
+					outptr = g_stpcpy (outptr, "<div>");
+					priv->div_open = TRUE;
+				}
+
 				outptr = check_size (mime_filter, outptr, &outend, 25);
 				outptr += sprintf (outptr, "<font color=\"#%06x\">", (priv->color & 0xffffff));
 			}
@@ -352,6 +365,13 @@ html_convert (CamelMimeFilter *mime_filter,
 			goffset skip = 0;
 
 			depth = citation_depth (start, inend, &skip);
+
+			if (priv->div_open && depth != priv->blockquote_depth) {
+				outptr = check_size (mime_filter, outptr, &outend, 7);
+				outptr = g_stpcpy (outptr, "</div>");
+				priv->div_open = FALSE;
+			}
+
 			while (priv->blockquote_depth < depth) {
 				outptr = check_size (mime_filter, outptr, &outend, 25);
 				outptr = g_stpcpy (outptr, "<blockquote type=\"cite\">");
@@ -371,11 +391,23 @@ html_convert (CamelMimeFilter *mime_filter,
 			start += skip;
 
 		} else if (priv->flags & CAMEL_MIME_FILTER_TOHTML_CITE) {
+			if ((priv->flags & CAMEL_MIME_FILTER_TOHTML_DIV) != 0 && !priv->div_open) {
+				outptr = check_size (mime_filter, outptr, &outend, 6);
+				outptr = g_stpcpy (outptr, "<div>");
+				priv->div_open = TRUE;
+			}
+
 			outptr = check_size (mime_filter, outptr, &outend, 6);
 			outptr = g_stpcpy (outptr, "&gt; ");
 			priv->column += 2;
 		}
 
+		if ((priv->flags & CAMEL_MIME_FILTER_TOHTML_DIV) != 0 && !priv->div_open) {
+			outptr = check_size (mime_filter, outptr, &outend, 6);
+			outptr = g_stpcpy (outptr, "<div>");
+			priv->div_open = TRUE;
+		}
+
 #define CONVERT_URLS (CAMEL_MIME_FILTER_TOHTML_CONVERT_URLS | CAMEL_MIME_FILTER_TOHTML_CONVERT_ADDRESSES)
 		if (priv->flags & CONVERT_URLS) {
 			gsize matchlen, len;
@@ -457,6 +489,17 @@ html_convert (CamelMimeFilter *mime_filter,
 				outptr = g_stpcpy (outptr, "<br>");
 			}
 
+			if (priv->div_open) {
+				if (inptr == start && *start != '\r' && *start != '\n' && !(priv->flags & CAMEL_MIME_FILTER_TOHTML_CONVERT_NL)) {
+					outptr = check_size (mime_filter, outptr, &outend, 5);
+					outptr = g_stpcpy (outptr, "<br>");
+				}
+
+				outptr = check_size (mime_filter, outptr, &outend, 7);
+				outptr = g_stpcpy (outptr, "</div>");
+				priv->div_open = FALSE;
+			}
+
 			outptr = append_string_verbatim (mime_filter, "\n", outptr, &outend);
 		}
 
@@ -472,6 +515,12 @@ html_convert (CamelMimeFilter *mime_filter,
 				inend,
 				outptr, &outend);
 
+		if (priv->div_open) {
+			outptr = check_size (mime_filter, outptr, &outend, 7);
+			outptr = g_stpcpy (outptr, "</div>");
+			priv->div_open = FALSE;
+		}
+
 		while (priv->blockquote_depth > 0) {
 			outptr = check_size (mime_filter, outptr, &outend, 14);
 			outptr = g_stpcpy (outptr, "</blockquote>");
@@ -587,6 +636,12 @@ camel_mime_filter_tohtml_new (CamelMimeFilterToHTMLFlags flags,
 	CamelMimeFilterToHTMLPrivate *priv;
 	gint i;
 
+	/* Prefer PRE over DIV, when used together (which they should not) */
+	if ((flags & (CAMEL_MIME_FILTER_TOHTML_PRE | CAMEL_MIME_FILTER_TOHTML_DIV)) ==
+	    (CAMEL_MIME_FILTER_TOHTML_PRE | CAMEL_MIME_FILTER_TOHTML_DIV)) {
+		flags = flags & ~CAMEL_MIME_FILTER_TOHTML_DIV;
+	}
+
 	filter = g_object_new (CAMEL_TYPE_MIME_FILTER_TOHTML, NULL);
 	priv = CAMEL_MIME_FILTER_TOHTML (filter)->priv;
 
-- 
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