CONFIGURE: Generate html README and NEWS by default on macOS

There was already a configure option to specify a output format other
than plain text, but this had to be specified explicitely when
executing configure. Now the ports can define a default other than
plain text.

On macOS now by default pandoc generate html output. It could
in theory also generate rtf, but those are not properly displayed
by TextEdit, and in addition TextEdit cannot handle link internal
to the document (such as for the TOC). But if we are fine with
no link for the TOC, we could pipe the pandoc html output with
textutil to generate the RTF documents.

Also this change allows to have an extension for the pandoc output
files. By default this is empty for plain text (as before) and
the same as the format otherwise (for example .rtf or .html).

3 files changed, 32 insertions, 5 deletions

diff --git a/.gitignore b/.gitignore
index ed6b6e02d2..2708700d6a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -38,7 +38,9 @@ lib*.a
 /scummvm-conf.cpp
 /tmp_*.cpp
 /README
+/README.html
 /NEWS
+/NEWS.html
 
 /build
 /staging
diff --git a/Makefile.common b/Makefile.common
index b058ae9a13..c6c47fd075 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -13,7 +13,7 @@ all: $(EXECUTABLE).dwp
 endif
 
 ifdef USE_PANDOC
-all: README NEWS
+all: README$(PANDOCEXT) NEWS$(PANDOCEXT)
 endif
 
 ######################################################################
@@ -237,10 +237,10 @@ VERFILE := $(DISTDIR)/$(DISTNAME)/base/internal_version.h
 
 ifdef USE_PANDOC
 # Convert README.md and NEWS.md to plain text for any platform that might require it
-README: ${srcdir}/README.md
+README$(PANDOCEXT): ${srcdir}/README.md
 	$(QUIET_PANDOC)$(PANDOC) -f gfm -t $(PANDOCFORMAT) -o $@ $<
 
-NEWS: ${srcdir}/NEWS.md
+NEWS$(PANDOCEXT): ${srcdir}/NEWS.md
 	$(QUIET_PANDOC)$(PANDOC) -f gfm -t $(PANDOCFORMAT) -o $@ $<
 endif
 
@@ -275,7 +275,7 @@ dist-src: \
 # Common files
 DIST_FILES_DOCS:=$(addprefix $(srcdir)/,AUTHORS COPYING COPYING.BSD COPYING.LGPL COPYING.FREEFONT COPYRIGHT NEWS.md README.md)
 ifdef USE_PANDOC
-DIST_FILES_DOCS+=README NEWS
+DIST_FILES_DOCS+=README$(PANDOCEXT) NEWS$(PANDOCEXT)
 endif
 
 DIST_FILES_DOCS_languages=cz da de es fr it no-nb se
diff --git a/configure b/configure
index 1289b2158f..62b43d35ab 100755
--- a/configure
+++ b/configure
@@ -229,7 +229,8 @@ NASM=""
 _tainted_build=no
 PANDOC=""
 _pandocpath="$PATH"
-_pandocformat="plain"
+_pandocformat="default"
+_pandocext="default"
 # The following variables are automatically detected, and should not
 # be modified otherwise. Consider them read-only.
 _posix=no
@@ -2705,6 +2706,16 @@ case $_host_os in
 				echo "Could not determine path for Xcode Tools"
 			fi
 		fi
+
+		# Use pandoc to generate README and NEWS file for the bundle
+		# Also default to  HTML rather than plain text as it gives a nicer
+		# formating, especially for the README. We could consider using RTF
+		# as well, but TextEdit does not support links within the document,
+		# and having a TOC with links, which we do with html, is quite convenient.
+		_pandoc=yes
+		if test "$_pandocformat" = "default"; then
+			_pandocformat="html"
+		fi
 		;;
 	dreamcast)
 		append_var DEFINES "-D__DC__"
@@ -5141,6 +5152,19 @@ fi
 
 define_in_config_if_yes $_pandoc 'USE_PANDOC'
 
+# Default to plain text output for pandoc
+if test -z "$_pandocformat" -o "$_pandocformat" = "default"; then
+	_pandocformat="plain"
+fi
+
+if test "$_pandocext" = "default"; then
+	if test "$_pandocformat" = plain; then
+		_pandocext=""
+	else
+		_pandocext=".$_pandocformat"
+	fi
+fi
+
 #
 # Enable vkeybd / keymapper / event recorder
 #
@@ -5619,6 +5643,7 @@ NASM := $NASM
 NASMFLAGS := $NASMFLAGS
 PANDOC := $PANDOC
 PANDOCFORMAT := $_pandocformat
+PANDOCEXT := $_pandocext
 ZLIB_LIBS := $ZLIB_LIBS
 ZLIB_CFLAGS := $ZLIB_CFLAGS