Support scrolling ANSI messages in preview and view modes

Supports mixed Ctrl-A and ANSI messages.

ANSIs of any length should display correctly.

ANSIs wider than 79 columns will be truncated (not horizontally scrollable).

Animated ANSIs will not render with their animation sequences in tact. :-(

exec/msglist.js

@@ -71,6 +71,8 @@ require('sbbsdefs.js', 'LEN_ALIAS');
 require("utf8_cp437.js", 'utf8_cp437');
 require("file_size.js", 'file_size_str');
 require("html2asc.js", 'html2asc');
+require("graphic.js", 'Graphic');
+var ansiterm = require("ansiterm_lib.js", 'expand_ctrl_a');
 load('822header.js');
 var hexdump = load('hexdump_lib.js');
 var mimehdr = load('mimehdr.js');
@@ -572,6 +574,7 @@ function get_msg_lines(msgbase, msg, hdr, source, hex, wrap, chop)
 	msg.source = (source===true && !hex);
 	msg.wrapped = false;
 	msg.html = false;
+	msg.ansi = false;
 	var text;
 	if(!hdr) {
 		console.print(format(preparing_fmt, options.reading_message_text || "\x01[Reading message text ..."));
@@ -611,12 +614,21 @@ function get_msg_lines(msgbase, msg, hdr, source, hex, wrap, chop)
 			}
 		}
 		text = text.replace(/\xff/g, ' ');	// Use a regular old space for nbsp
-		if(msg.wrapped) {
-			console.print(format(preparing_fmt, options.wrapping_lines || "\x01[Wrapping lines ..."));
-			text = word_wrap(text, console.screen_columns - 1, (msg.columns || 80) - 1).split('\n');
+		msg.ansi = text.indexOf("\x1b[") >= 0;
+		if(msg.ansi) {
+			var graphic = new Graphic(console.screen_columns, 10);
+			graphic.auto_extend = true;
+			graphic.ANSI = ansiterm.expand_ctrl_a(text);
+			graphic.width = console.screen_columns - 1;
+			text = graphic.MSG.split('\n');
 		} else {
-			console.print(format(preparing_fmt, options.splitting_lines || "\x01[Splitting lines ..."));
-			text = line_split(text, chop);
+			if(msg.wrapped) {
+				console.print(format(preparing_fmt, options.wrapping_lines || "\x01[Wrapping lines ..."));
+				text = word_wrap(text, console.screen_columns - 1, (msg.columns || 80) - 1).split('\n');
+			} else {
+				console.print(format(preparing_fmt, options.splitting_lines || "\x01[Splitting lines ..."));
+				text = line_split(text, chop);
+			}
 		}
 		while(text.length && !text[0].trim().length)
 			text.shift(); // Remove initial blank lines
@@ -715,6 +727,8 @@ function content_description(msg)
 		desc.push('header');
 	else if(msg.hex)
 		desc.push('hex-dumpped');
+	else if(msg.ansi)
+			desc.push('ANSI');
 	else {
 		if(msg.wrapped)
 			desc.push('wrapped');