# HG changeset patch
# User yiyus@1936
# Date 1248189919 -7200
# Node ID fa51423d52928d8eaac248cb6a2ea78afd99324e
# Parent  8d0cd6f66ee75cfa8e85583a9af19474bfbff20f
Back to the default branch

diff -r 8d0cd6f66ee7 -r fa51423d5292 md2html.awk
--- a/md2html.awk	Thu Jun 04 17:37:05 2009 -0500
+++ b/md2html.awk	Tue Jul 21 17:25:19 2009 +0200
@@ -1,176 +1,427 @@
 #!/bin/awk -f
+#
+# by: Jesus Galan (yiyus) 2009
+#
+# Usage: md2html.awk file.md > file.html
+# See: http://4l77.com/src/md2html.awk
 
-# md2html.awk
-# by: Jesus Galan (yiyus) <yiyu.jgl@gmail>, May 2009
-# Usage:
-# 	md2html file.md > file.html
-# Options: -v esc=false to not escape html
-
-function newblock(nblock){
-	if(text)
-		print "<" block ">" text "</" block ">";
-	text = "";
-	block = nblock ? nblock : "p";
+function eschtml(t) {
+	gsub("&", "\\&amp;", t);
+	gsub("<", "\\&lt;", t);
+	return t;
 }
 
-function subinline(tgl, inl){
-	while(match($0, tgl)){
-		if (inline[ni] == inl)
-			ni -= sub(tgl, "</" inl ">");
-		else if (sub(tgl, "<" inl ">"))
-			inline[++ni] = inl;
+function oprint(t){
+	if(nr == 0)
+		print t;
+	else
+		otext = otext "\n" t;
+}
+
+function subref(id){
+	for(; nr > 0 && sub("<<" id, ref[id], otext); nr--);
+	if(nr == 0 && otext) {
+		print otext;
+		otext = "";
 	}
 }
 
-function dolink(href, lnk){
-	# Undo escaped html in uris
-	gsub(/&amp;/, "\\&", href);
-	gsub(/&lt;/, "<", href);
-	gsub(/&gt;/, ">", href);
-	# & can be tricky, and not standard:
-	gsub(/&/, "\\\\\\&", href);
-	gsub(/&/, "\\\\\\&", lnk);
-	return "<a href=\"" href "\">" lnk "</a>";
+function nextil(t) {
+	if(!match(t, /[`<&\[*_\\-]|(\!\[)/))
+		return t;
+	t1 = substr(t, 1, RSTART - 1);
+	tag = substr(t, RSTART, RLENGTH);
+	t2 = substr(t, RSTART + RLENGTH);
+	if(ilcode && tag != "`")
+		return eschtml(t1 tag) nextil(t2);
+	# Backslash escaping
+	if(tag == "\\"){
+		if(match(t2, /^[\\`*_{}\[\]()#+\-\.!]/)){
+			tag = substr(t2, 1, 1);
+			t2 = substr(t2, 2);
+		}
+		return t1 tag nextil(t2);
+	}
+	# Dashes
+	if(tag == "-"){
+		if(sub(/^-/, "", t2))
+			tag = "&#8212;";
+		return t1 tag nextil(t2);
+	}
+	# Inline Code
+	if(tag == "`"){
+		if(sub(/^`/, "", t2)){
+			if(!match(t2, /``/))
+				return t1 "&#8221;" nextil(t2);
+			ilcode2 = !ilcode2;
+		}
+		else if(ilcode2)
+			return t1 tag nextil(t2);
+		tag = "<code>";
+		if(ilcode){
+			t1 = eschtml(t1);
+			tag = "</code>";
+		}
+		ilcode = !ilcode;
+		return t1 tag nextil(t2);
+	}
+	if(tag == "<"){
+	# Autolinks
+		if(match(t2, /^[^ 	]+[\.@][^ 	]+>/)){
+			url = eschtml(substr(t2, 1, RLENGTH - 1));
+			t2 = substr(t2, RLENGTH + 1);
+			linktext = url;
+			if(match(url, /@/) && !match(url, /^mailto:/))
+				url = "mailto:" url;
+			return t1 "<a href=\"" url "\">" linktext "</a>" nextil(t2);
+		}
+	# Html tags
+		if(match(t2, /^[A-Za-z\/!][^>]*>/)){
+			tag = tag substr(t2, RSTART, RLENGTH);
+			t2 = substr(t2, RLENGTH + 1);
+			return t1 tag nextil(t2);
+		}
+		return t1 "&lt;" nextil(t2);
+	}
+	# Html special entities
+	if(tag == "&"){
+		if(match(t2, /^#?[A-Za-z0-9]+;/)){
+			tag = tag substr(t2, RSTART, RLENGTH);
+			t2 = substr(t2, RLENGTH + 1);
+			return t1 tag nextil(t2);
+		}
+		return t1 "&amp;" nextil(t2);
+	}
+	# Images
+	if(tag == "!["){
+		if(!match(t2, /(\[.*\])|(\(.*\))/))
+			return t1 tag nextil(t2);
+		match(t2, /^[^\]]*/);
+		alt = substr(t2, 1, RLENGTH);
+		t2 = substr(t2, RLENGTH + 2);
+		if(match(t2, /^\(/)){
+			# Inline
+			sub(/^\(/, "", t2);
+			match(t2, /^[^\)]+/);
+			url = eschtml(substr(t2, 1, RLENGTH));
+			t2 = substr(t2, RLENGTH + 2);
+			title = "";
+			if(match(url, /[ 	]+\".*\"[ 	]*$/)) {
+				title = substr(url, RSTART, RLENGTH);
+				url = substr(url, 1, RSTART - 1);
+				match(title, /\".*\"/);
+				title = " title=\"" substr(title, RSTART + 1, RLENGTH - 2) "\"";
+			}
+			if(match(url, /^<.*>$/))
+				url = substr(url, 2, RLENGTH - 2);
+			return t1 "<img src=\"" url "\" alt=\"" alt "\"" title " />" nextil(t2);
+		}
+		else{
+			# Referenced
+			sub(/^ ?\[/, "", t2);
+			id = alt;
+			if(match(t2, /^[^\]]+/))
+				id = substr(t2, 1, RLENGTH);
+			t2 = substr(t2, RLENGTH + 2);
+			if(ref[id])
+				r = ref[id];
+			else{
+				r = "<<" id;
+				nr++;
+			}
+			return t1 "<img src=\"" r "\" alt=\"" alt "\" />" nextil(t2);
+		}
+	}
+	# Links
+	if(tag == "["){
+		if(!match(t2, /(\[.*\])|(\(.*\))/))
+			return t1 tag nextil(t2);
+		match(t2, /^[^\]]*(\[[^\]]*\][^\]]*)*/);
+		linktext = substr(t2, 1, RLENGTH);
+		t2 = substr(t2, RLENGTH + 2);
+		if(match(t2, /^\(/)){
+			# Inline
+			match(t2, /^[^\)]+(\([^\)]+\)[^\)]*)*/);
+			url = substr(t2, 2, RLENGTH - 1);
+			pt2 = substr(t2, RLENGTH + 2);
+			title = "";
+			if(match(url, /[ 	]+\".*\"[ 	]*$/)) {
+				title = substr(url, RSTART, RLENGTH);
+				url = substr(url, 1, RSTART - 1);
+				match(title, /\".*\"/);
+				title = " title=\"" substr(title, RSTART + 1, RLENGTH - 2) "\"";
+			}
+			if(match(url, /^<.*>$/))
+				url = substr(url, 2, RLENGTH - 2);
+			url = eschtml(url);
+			return t1 "<a href=\"" url "\"" title ">" nextil(linktext) "</a>" nextil(pt2);
+		}
+		else{
+			# Referenced
+			sub(/^ ?\[/, "", t2);
+			id = linktext;
+			if(match(t2, /^[^\]]+/))
+				id = substr(t2, 1, RLENGTH);
+			t2 = substr(t2, RLENGTH + 2);
+			if(ref[id])
+				r = ref[id];
+			else{
+				r = "<<" id;
+				nr++;
+			}
+			pt2 = t2;
+			return t1 "<a href=\"" r "\" />" nextil(linktext) "</a>" nextil(pt2);
+		}
+	}
+	# Emphasis
+	if(match(tag, /[*_]/)){
+		ntag = tag;
+		if(sub("^" tag, "", t2)){
+			if(stag[ns] == tag && match(t2, "^" tag))
+				t2 = tag t2;
+			else
+				ntag = tag tag
+		}
+		n = length(ntag);
+		tag = (n == 2) ? "strong" : "em";
+		if(match(t1, / $/) && match(t2, /^ /))
+			return t1 tag nextil(t2);
+		if(stag[ns] == ntag){
+			tag = "/" tag;
+			ns--;
+		}
+		else
+			stag[++ns] = ntag;
+		tag = "<" tag ">";
+		return t1 tag nextil(t2);
+	}
+}
+
+function inline(t) {
+	ilcode = 0;
+	ilcode2 = 0;
+	ns = 0;
+	
+	return nextil(t);
+}
+
+function printp(tag) {
+	if(!match(text, /^[ 	]*$/)){
+		text = inline(text);
+		if(tag != "")
+			oprint("<" tag ">" text "</" tag ">");
+		else
+			oprint(text);
+	}
+	text = "";
 }
 
 BEGIN {
-	ni = 0;	# inlines
-	nl = 0;	# nested lists
+	blank = 0;
+	code = 0;
+	hr = 0;
+	html = 0;
+	nl = 0;
+	nr = 0;
+	otext = "";
 	text = "";
-	block = "p";
+	par = "p";
 }
 
-# Escape html
-esc != "false" {
-	gsub("&", "\\&amp;")
-	gsub("<", "\\&lt;")
-	gsub(">", "\\&gt;")
-}
+# References
+!code && /^ *\[[^\]]*\]:[ 	]+/ {
+	sub(/^ *\[/, "");
+	match($0, /\]/);
+	id = substr($0, 1, RSTART - 1);
+	sub(id "\\]:[ 	]+", "");
+	title = "";
+	if(match($0, /\".*\"$/))
+		title = "\" title=\"" substr($0, RSTART + 1, RLENGTH - 2);
+	sub(/[ 	]+\".*\"$/, "");
+	url = eschtml($0);
+	ref[id] = url title;
 
-# Horizontal rules (_ is not in markdown)
-/^[ 	]*([-*_] ?)+[ 	]*$/ && text == "" {
-	print "<hr>";
+	subref(id);
 	next;
 }
 
-# Tables (not in markdown)
-# Syntax:
-# 		Right Align| 	Center Align	|Left Align
-/([ 	]\|)|(\|[ 	])/ {
-	if(block != "table")
-		newblock("table");
-	nc = split($0, cells, "|");
-	$0 = "<tr>\n";
-	for(i = 1; i <= nc; i++){
-		align = "left";
-		if(sub(/^[ 	]+/, "", cells[i])){
-			if(sub(/[ 	]+$/, "", cells[i]))
-				align = "center";
-			else
-				align = "right";
-		}
-		sub(/[ 	]+$/,"", cells[i]);
-		$0 = $0 "<td align=\"" align "\">" cells[i] "</td>\n";
-	}
-	$0 = $0 "</tr>";
+# html
+!html && /^<(address|blockquote|center|dir|div|dl|fieldset|form|h[1-6r]|\
+isindex|menu|noframes|noscript|ol|p|pre|table|ul|!--)/ {
+	if(code)
+		oprint("</pre></code>");
+	for(; !text && block[nl] == "blockquote"; nl--)
+		oprint("</blockquote>");
+	match($0, /^<(address|blockquote|center|dir|div|dl|fieldset|form|h[1-6r]|\
+	isindex|menu|noframes|noscript|ol|p|pre|table|ul|!--)/);
+	htag = substr($0, 2, RLENGTH - 1);
+	if(!match($0, "(<\\/" htag ">)|((^<hr ?\\/?)|(--)>$)"))
+		html = 1;
+	if(html && match($0, /^<hr/))
+		hr = 1;
+	oprint($0);
+	next;
 }
 
-# Ordered and unordered (possibly nested) lists
-/^[ 	]*([*+-]|(([0-9]+[\.-]?)+))[ 	]/ {
-	newblock("li");
-	nnl = 1;
-	while(match($0, /^[ 	]/)){
-		sub(/^[ 	]/,"");
-		nnl++;
-	}
-	while(nl > nnl)
-		print "</" list[nl--] ">";
-	while(nl < nnl){
-		list[++nl] = "ol";
-		if(match($0, /^[*+-]/))
-			list[nl] = "ul";
-		print "<" list[nl] ">";
-	}
-	sub(/^([*+-]|(([0-9]+[\.-]?)+))[ 	]/,"");
+html && (/(^<\/(address|blockquote|center|dir|div|dl|fieldset|form|h[1-6r]|\
+isindex|menu|noframes|noscript|ol|p|pre|table|ul).*)|(--)>$/ ||
+(hr && />$/)) {
+	html = 0;
+	hr = 0;
+	oprint($0);
+	next;
 }
 
-# Multi line list items
-block == "li" {
-	sub(/^( *)|(	*)/,"");
+html {
+	oprint($0);
+	next;
+}
+
+# List and quote blocks
+
+#   Remove indentation
+{
+	for(nnl = 0; nnl < nl; nnl++)
+		if((match(block[nnl + 1], /[ou]l/) && !sub(/^(    |	)/, "")) || \
+		(block[nnl + 1] == "blockquote" && !sub(/^> ?/, "")))
+			break;
+}
+nnl < nl && !blank && text && ! /^ ? ? ?([*+-]|([0-9]+\.)+)( +|	)/ { nnl = nl; }
+#   Quote blocks
+{ 
+	while(sub(/^> /, ""))
+		nblock[++nnl] = "blockquote";
+}
+#   Horizontal rules
+{ hr = 0; }
+(blank || (!text && !code)) && /^ ? ? ?([-*_][ 	]*)([-*_][ 	]*)([-*_][ 	]*)+$/ {
+	if(code){
+		oprint("</pre></code>");
+		code = 0;
+	}
+	blank = 0;
+	nnl = 0;
+	hr = 1;
+}
+#   List items
+block[nl] ~ /[ou]l/ && /^$/ {
+	blank = 1;
+	next;
+}
+{ newli = 0; }
+!hr && (nnl != nl || !text || block[nl] ~ /[ou]l/) && /^ ? ? ?[*+-]( +|	)/ {
+	sub(/^ ? ? ?[*+-]( +|	)/, "");
+	nnl++;
+	nblock[nnl] = "ul";
+	newli = 1;
+}
+(nnl != nl || !text || block[nl] ~ /[ou]l/) && /^ ? ? ?([0-9]+\.)+( +|	)/ {
+	sub(/^ ? ? ?([0-9]+\.)+( +|	)/, "");
+	nnl++;
+	nblock[nnl] = "ol";
+	newli = 1;
+}
+newli { 
+	if(blank && nnl == nl && !par)
+		par = "p";
+	blank = 0;
+	printp(par);
+	if(nnl == nl && block[nl] == nblock[nl])
+		oprint("</li><li>");
+}
+blank && ! /^$/ {
+	if(match(block[nnl], /[ou]l/) && !par)
+		par = "p";
+	printp(par);
+	par = "p";
+	blank = 0;
+}
+		
+# Close old blocks and open new ones
+nnl != nl || nblock[nl] != block[nl] {
+	if(code){
+		oprint("</pre></code>");
+		code = 0;
+	}
+	printp(par);
+	b = (nnl > nl) ? nblock[nnl] : block[nnl];
+	par = (match(b, /[ou]l/)) ? "" : "p";
+}
+nnl < nl || (nnl == nl && nblock[nl] != block[nl]) {
+	for(; nl > nnl || (nnl == nl && pblock[nl] != block[nl]); nl--){
+		if(match(block[nl], /[ou]l/))
+			oprint("</li>");
+		oprint("</" block[nl] ">");
+	}
+}
+nnl > nl {
+	for(; nl < nnl; nl++){
+		block[nl + 1] = nblock[nl + 1];
+		oprint("<" block[nl + 1] ">");
+		if(match(block[nl + 1], /[ou]l/))
+			oprint("<li>");
+	}
+}
+hr {
+	oprint("<hr>");
+	next;
 }
 
 # Code blocks
-/^(    |	)/ {
-	if(block != "pre")
-		newblock("pre");
-	sub(/^(    |	)/, "");
-	text = text $0 "\n";
+code && /^$/ { 
+	if(blanK)
+		oprint("");
+	blank = 1;
+	next;
+}
+!text && sub(/^(	|    )/, "") {
+	if(blanK)
+		oprint("");
+	blank = 0;
+	if(!code)
+		oprint("<code><pre>");
+	code = 1;
+	$0 = eschtml($0);
+	oprint($0);
+	next;
+}
+code {
+	oprint("</pre></code>");
+	code = 0;
+}
+
+# Setex-style Headers
+text && /^=+$/ {printp("h1"); next;}
+text && /^-+$/ {printp("h2"); next;} 
+
+# Atx-Style headers
+/^#+/ && (!newli || par=="p" || /^##/) {
+	for(n = 0; n < 6 && sub(/^# */, ""); n++)
+		sub(/#$/, "");
+	par = "h" n;
+}
+
+# Paragraph	
+/^$/ {
+	printp(par);
+	par = "p";
 	next;
 }
 
-# Paragraph
-/^$/ {
-	newblock();
-	while(nl > 0)
-		print "</" list[nl--] ">";
-}
-
-# Setex-style Headers
-# (Plus h3 with underscores.)
-/^=+$/ {
-	block = "h" 1;
-	next;
-}
-
-/^-+$/ {
-	block = "h" 2;
-	next;
-}
-
-/^_+$/ {
-	block = "h" 3;
-	next;
-}
-
-# Atx-style headers
-/^#/ {
-	newblock();
-	match($0, /#+/);
-	n = RLENGTH;
-	if(n > 6)
-		n = 6;
-	text = substr($0, RLENGTH + 1);
-	block = "h" n;
-	next;
-}
-
-// {
-	# Images
-	while(match($0, /!\[[^\]]+\]\([^\)]+\)/)){
-		split(substr($0, RSTART + 2, RLENGTH - 3), a, /\]\(/);
-		sub(/!\[[^\]]+\]\([^\)]+\)/, "<img src=\"" a[2] "\" alt=\"" a[1] "\">");
-	}
-	# Links
-	while(match($0, /\[[^\]]+\]\([^\)]+\)/)){
-		split(substr($0, RSTART + 1, RLENGTH - 2), a, /\]\(/);
-		sub(/\[[^\]]+\]\([^\)]+\)/, dolink(a[2], a[1]));
-	}
-	# Auto links (uri matching is poor)
-	na = split($0, a, /(^\()|[ 	]|([,\.\)]([ 	]|$))/);
-	for(i = 1; i <= na; i++)
-		if(match(a[i], /^(((https?|ftp|file|news|irc):\/\/)|(mailto:)).+$/))
-			sub(a[i], dolink(a[i], a[i]));
-	# Inline
-	subinline("(\\*\\*)|(__)", "strong");
-	subinline("\\*", "em");
-	subinline("`", "code");
-	text = text (text ? " " : "") $0;
-}
+# Add text
+{ text = (text ? text " " : "") $0; }
 
 END {
-	while(ni > 0)
-		text = text "</" inline[ni--] ">";
-	newblock();
-	while(nl > 0)
-		print "</" list[nl--] ">";
+	if(code){
+		oprint("</pre></code>");
+		code = 0;
+	}
+	printp(par);
+	for(; nl > 0; nl--){
+		if(match(block[nl], /[ou]l/))
+			oprint("</li>");
+		oprint("</" block[nl] ">");
+	}
+	gsub(/<<[^\"]*/, "", otext);
+	print(otext);
 }