module.exports = function(params, callback) {
'use strict';
var path = require('path');
var async = require('async');
var _ = require('lodash');
var assemble = params.assemble;
var grunt = params.grunt;
var options = assemble.options;
var pages = options.pages;
var defaults = options.permalink;
var escRegEx = function(string) {
return string.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, "\\$1");
};
var PATH_SEP = path.sep.slice(-1);
var INDEX = 'index.html';
var INDEX_RE = new RegExp(escRegEx(PATH_SEP + INDEX) + '$');
// parse lodash template <%= %>
var parseTpl = function(input, data, page) {
try {
return _.template(input, data);
} catch (error) {
grunt.fail.fatal(error.message + ' at ' + page.src);
}
};
// convert {{ variable }} to <%= variable %>
// {{{{ not_variable }}}} to {{ not_variable }}
var unescTpl = function(input) {
return input.replace(/\{{2,}/g, function(match) {
return match.length > 2 ? match.substr(2) : '<%=';
}).replace(/\}{2,}/g, function(match) {
return match.length > 2 ? match.substr(2) : '%>';
});
};
// standardize permalink output
var standard = function(permalink) {
permalink = permalink || '';
if (permalink.slice(0, 1) !== PATH_SEP) {
permalink = PATH_SEP + permalink;
}
permalink = permalink.replace(INDEX_RE, PATH_SEP);
return permalink;
};
if (_.isString(defaults) && !_.isEmpty(defaults)) {
defaults = unescTpl(defaults);
}
async.each(pages, function(page, next) {
page.data = page.data || {};
var yfm = page.data;
var permalink = defaults;
var dirname = page.dirname;
if (page.filePair && page.filePair.dest) {
dirname = page.filePair.destForPermalink ||
page.filePair.dest_for_permalink ||
page.filePair.dest;
}
if (!_.isUndefined(yfm.permalink)) {
permalink = yfm.permalink;
}
if (!_.isEmpty(permalink)) {
var data = _.assign({}, options, page, yfm);
var permalinks;
if (_.isString(permalink)) {
permalink = unescTpl(permalink);
permalink = parseTpl(permalink, data, page);
permalink = permalink.trim();
permalinks = permalink.split('\n');
} else if (_.isArray(permalink)) {
permalinks = permalink;
} else {
grunt.fail.fatal('the permalink of ' + page.src +
' is neither a string nor an array');
}
for (var i = permalinks.length - 1; i >= 0; i--) {
var permalink = permalinks[i];
if (_.isEmpty(permalink)) continue;
permalink = unescTpl(permalink);
permalink = parseTpl(permalink, data, page);
permalink = permalink.trim();
if (_.isEmpty(permalink)) continue;
page.dest = path.join(dirname, permalink);
if (page.dest.slice(-1) === PATH_SEP) {
page.dest = path.join(page.dest, 'index.html');
}
page.data.permalink = standard(permalink);
if (i > 0) {
page = _.cloneDeep(page);
pages.push(page);
}
}
}
if (!page.data.permalink) {
page.data.permalink = page.dest.substr(dirname.length);
}
page.data.permalink = standard(page.data.permalink);
if (typeof options.permalinkCallback === 'function') {
options.permalinkCallback.call(page);
}
next();
});
callback();
};