make/scripts/pandoc-troff-manpage-filter.js
branchihse-manpages-branch
changeset 57051 d8697832a650
parent 57049 d13c49f43710
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/make/scripts/pandoc-troff-manpage-filter.js	Mon Dec 03 18:33:11 2018 +0100
@@ -0,0 +1,142 @@
+//
+// Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+//
+// This code is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License version 2 only, as
+// published by the Free Software Foundation.
+//
+// This code is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// version 2 for more details (a copy is included in the LICENSE file that
+// accompanied this code).
+//
+// You should have received a copy of the GNU General Public License version
+// 2 along with this work; if not, write to the Free Software Foundation,
+// Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+// or visit www.oracle.com if you need additional information or have any
+// questions.
+//
+
+//
+// Traverse a tree of pandoc format objects, calling callback on each
+// element, and replacing it if callback returns a new object.
+//
+// Inspired by the walk method in
+// https://github.com/jgm/pandocfilters/blob/master/pandocfilters.py
+//
+function traverse(obj, callback) {
+    if (Array.isArray(obj)) {
+        var processed_array = [];
+        obj.forEach(function(elem) {
+            if (elem === Object(elem) && elem.t) {
+                var replacement = callback(elem.t, elem.c || []);
+                if (!replacement) {
+                    // no replacement object returned, use original
+                    processed_array.push(traverse(elem, callback));
+                } else if (Array.isArray(replacement)) {
+                    // array of objects returned, splice all elements into array
+                    replacement.forEach(function(repl_elem) {
+                        processed_array.push(traverse(repl_elem, callback));
+                    })
+                } else {
+                    // replacement object given, traverse it
+                    processed_array.push(traverse(replacement, callback));
+                }
+            } else {
+                processed_array.push(traverse(elem, callback));
+            }
+        })
+        return processed_array;
+    } else if (obj === Object(obj)) {
+        var processed_obj = {};
+        Object.keys(obj).forEach(function(key) {
+            processed_obj[key] = traverse(obj[key], callback);
+        })
+        return processed_obj;
+    } else {
+        return obj;
+    }
+}
+
+//
+// Helper constructors to create pandoc format objects
+//
+function Space() {
+    return { 't': 'Space', 'c': [] };
+}
+
+function Str(value) {
+    return { 't': 'Str', 'c': value };
+}
+
+function Strong(value) {
+    return { 't': 'Strong', 'c': value };
+}
+
+function Header(value) {
+    return { 't': 'Header', 'c': value };
+}
+
+//
+// Callback to change all Str texts to upper case
+//
+function uppercase(type, value) {
+    if (type === 'Str') {
+        return Str(value.toUpperCase());
+    }
+}
+
+//
+// Main callback function that performs our man page AST rewrites
+//
+function manpage_filter(type, value) {
+    // If it is a header, decrease the heading level by one, and
+    // if it is a level 1 header, convert it to upper case.
+    if (type === 'Header') {
+        value[0] = Math.max(1, value[0] - 1);
+        if (value[0] == 1) {
+            return Header(traverse(value, uppercase));
+        }
+    }
+
+    // Man pages does not have superscript. We use it for footnotes, so
+    // enclose in [...] for best representation.
+    if (type === 'Superscript') {
+        return [ Str('['), value[0], Str(']') ];
+    }
+
+    // If it is a link, put the link name in bold. If it is an external
+    // link, put it in brackets. Otherwise, it is either an internal link
+    // (like "#next-heading"), or a relative link to another man page
+    // (like "java.html"), so remove it for man pages.
+    if (type === 'Link') {
+        var target = value[2][0];
+        if (target.match(/^http[s]?:/)) {
+            return [ Strong(value[1]), Space(), Str('[' + target + ']') ];
+        } else {
+            return Strong(value[1]);
+        }
+    }
+}
+
+//
+// Main function
+//
+function main() {
+    var input = "";
+    while (line = readLine()) {
+        input = input.concat(line);
+    }
+    var json = JSON.parse(input);
+
+    var transformed_json = traverse(json, manpage_filter);
+
+    print(JSON.stringify(transformed_json));
+}
+
+// ... and execute it
+main();