songty/Static-site-generator

'use strict';

var fs = require('fs');
var options = { encoding: 'utf8' };
var path = require('path');

/**
 * Reads files at a path
 *
 * @function
 * @param {string} ipath - The path at which to read
 * @param {function} cb - The callback to call. The callback receives two
 * arguments, `err`, an error, and `contents`, the contents of path file.
 */
var fileReader = module.exports.fileReader = function (textFile, cb) {
    fs.readFile(textFile, options, function(err, contents) {
        if (err) { return cb(err); }
        cb(null, contents);
    });
};

/**
 * Reads path to a file
 *
 * @function
 * @param {string} ipath - The path at which to read
 * @param {function} cb - The callback to call. The callback receives two
 * arguments, `err`, an error, and `files`, an array of file names.
 */
var pathReader = module.exports.pathReader = function (ipath, cb) {
    fs.readdir(ipath, function(err, files) {
        if (err) { return cb(err); }
        cb(null, files);
    });
};

/**
 * Writes files at a path
 *
 * @function
 * @param {string} newFile - The path at which to write
 * @param {function} contents - The contents be written.
 * @param {function} cb - The call back of this function return nothing.
 */
var fileWriter = module.exports.fileWriter = function (newFile, contents, cb) {
    fs.writeFile(newFile, contents, options, function (err) {
        if (err) {throw err;}
        cb();
    });
};

/**
 * Deltes all files in the generated directory
 *
 * @function
 * @param {function} cb - The call back to shreader.
 */
var fileShreader  = module.exports.fileShreader = function (cb) {
    var targetDir = path.join(__dirname, 'test/fixtures/generated');
    pathReader(targetDir, function(err, files) {
        if (err) { return cb(err); }
        var counter = 0;
        if (counter === files.length) {cb();}
        files.forEach(function(element) {
            var targetFile = path.join(targetDir, element);
            fs.unlink(targetFile, function() {
                // TODO: handle errors
                counter += 1;
                if (counter === files.length) { cb(); }     
            });
        });
    });
};

/**
 * Check if the string contains html
 *
 * @function
 * @param {string} ifile - return true if ifile is html.
 */
var isHtml = module.exports.isHtml = function(ifile) {
    return ifile.search('html') !== -1;
};

/**
 * Reading the contents of the source pages
 *
 * @function
 * @param {function} cb - The callback to call. The callback receives one
 * argument, `pages`, an array of html page file names.
 */
var sourcePage = module.exports.sourcePage = function(path, cb) {
    pathReader(path, function(err, files) {
        if (err) { return cb(err); }        
        var filtered = files.filter(isHtml);
        cb(filtered);
    });
};


/**
 * Reading the contents of the template pages
 * Splits the default template into two parts on {{ content }}
 *
 * @function
 * @param {string} path - The path of the source template.
 * @param {function} cb - The callback to call. The callback receives one
 * argument, `temp`, an array with two elemnts with contents split in half.
 */
var sourceTemplate = module.exports.sourceTemplate = function(path, cb) {
    fileReader(path, function(err, contents) {
        if (err) { return cb(err); }        
        if (contents.search("{{ content }}") !== -1) {
            var defaultTemplate = contents.split("{{ content }}");
            cb(defaultTemplate);
        }
    });
};

/**
 * Generates files using a default template
 * TODO: make function take arguments for template and page path.
 *
 * @function
 * @param {function} cb - The callback to call
 */
var generator = module.exports.generator = function (cb) {
    fileShreader(function() {
        var mP = __dirname;
        var tempPath = path.join(mP, 'test/fixtures/source/layouts/default.html');
        var pagePath = path.join(mP, 'test/fixtures/source/pages');
        sourceTemplate(tempPath, function(temp) {
            sourcePage(pagePath, function(pages) {
                var counter = 0;
                if (counter === pages.length) {cb();}
                pages.forEach(function(eachPage) {
                    fileReader(path.join(pagePath, eachPage), function(err, contents) {
                        if (err) { throw err; }
                        var resultArray = temp[0].concat(contents, temp[1]);
                        // console.log(resultArray);
                        var writePath = path.join(mP, 'test/fixtures/generated', eachPage);
                        fileWriter(writePath, resultArray, function(){});
                        //TODO: Errors handling
                        counter +=1;
                        if (counter === pages.length) {cb();}
                    });
                });

            });
        });
    }); 
};