Added basic terminal coloring to the infolines

js/hi01379.js

@@ -28,11 +28,74 @@ Hi01379 = (function(psGopherRequest) {
     }).join('\n')
   }
 
+  function terminalize(str, attrs) { // partial terminal styling support with ANSI codes
+    if(!attrs) attrs = [] // accept previous attributes array if present
+    var prevattrs = attrs.join(' ') // preserve stringified copy
+    var out = '', c, styleseq, sl, l = str.length, i, j, att, attindex, strattrs,
+        visualOpenTag='<span data-styling="%s">', visualCloseTag='</span>',
+        modes = ['', 'BB', 'FN', 'IT', 'UL', 'BL', '', 'IN', 'HI', 'ST']
+    for(i=0;i<l;i++) {
+      c = str[i]
+      if(c === '\x1b') { // escape character encountered
+        c = str[i+1] // get the next character, don't increase the counter yet
+        if(c === '[') { // ANSI sequence starting
+          i++ // increase the counter, now it's pointing to [
+          styleseq='' // init style sequence buffer
+          do { // read the style sequence until m character or any whitespace
+            c = str[++i] // increase the counter once more, [ is ignored
+            styleseq += c
+          } while(c !== 'm' && c !== ' ' && c !== '\t' && c !== '\r' && c !== '\n')
+          styleseq = styleseq.slice(0, -1).split(';') // attributes are delimited by ;
+          for(sl=styleseq.length,j=0;j<sl;j++) { // iterate over attributes in their order
+            att = parseInt(styleseq[j]) // in this case parseInt is more reliable than |0
+            if(att === 0) attrs = [] // reset all styling
+            else if(att >= 30 && att <= 37) attrs.push('FC'+(att-30)) // foreground color
+            else if(att >= 40 && att <= 47) attrs.push('BC'+(att-40)) // background color
+            else if(att < 10) attrs.push(modes[att]) // activate special modes
+            else if(att > 20 && att < 30) { // deactivate special modes
+              if(att === 22) { // also deactivate bold mode 1
+                attindex = attrs.indexOf('BB')
+                if(attindex > -1)
+                  attrs.splice(attindex, 1)
+              }
+              attindex = attrs.indexOf(modes[att - 20])
+              if(attindex > -1)
+                attrs.splice(attindex, 1)
+            }
+            else if(att === 39) { // reset only the foreground color
+              attrs = attrs.map(function(v) {
+                return v.startsWith('FC') ? '' : v
+              }).filter(String)
+            }
+            else if(att === 49) { // reset only the background color
+              attrs = attrs.map(function(v) {
+                return v.startsWith('BC') ? '' : v
+              }).filter(String)
+            }
+          }
+          // now we have our attrs array with all styling applied, output the tags
+          strattrs = attrs.join(' ')
+          if(strattrs != prevattrs) { // there are some changes
+            if(prevattrs != '') // previous attributes were not empty
+              out += visualCloseTag
+            if(strattrs) // current attributes are not empty
+              out += visualOpenTag.replace('%s', strattrs)
+            prevattrs = strattrs // update the previous attribute cache
+          }
+        } // don't add any processed characters "as is" to the output
+        else continue // skip the escape and proceed with the loop
+      }
+      else out += c // just append it to the output
+    } 
+    return {output: out, attrs: attrs} // return both output and remaining attributes
+  }
+
   function gophermapToHTML(gmap, chost, cport) {
     if(!cport) cport = 70
     if(!chost) chost = 'localhost'
     var lines = gmap.split(/\r?\n/), line, l = lines.length, i, lbr = '<br>',
         type, rest, desc, sel, host, port,
+        iattrs = [], istyled, // attribute cache and styled infomessage placeholder
         output = '', pretag = 'pre', preflag = false
     for(i=0;i<l;i++) {
       line = lines[i]
@@ -55,11 +118,14 @@ Hi01379 = (function(psGopherRequest) {
           preflag = true
           output += '<' + pretag + '>'
         }
-        output += desc + '\n'
+        istyled = terminalize(desc, iattrs)
+        iattrs = istyled.attrs
+        output += istyled.output + '\n'
       }
       else { //information messages ended, stop preformatting
         if(preflag) {
           preflag = false
+          iattrs = [] // reset info styling attributes
           output += '</' + pretag + '>'
         }
         if(desc = desc.trim()) { // ignore empty descriptions