Add gitbook init command, fixes GitbookIO#67

Author: Aaron O'Mullan

bin/gitbook.js

@@ -7,6 +7,7 @@ var prog = require('commander');
 
 var pkg = require('../package.json');
 var generators = require("../lib/generate").generators;
+var initDir = require("../lib/generate/init");
 var fs = require('../lib/generate/fs');
 
 var utils = require('./utils');
@@ -82,6 +83,14 @@ buildCommand(prog)
     });
 });
 
+prog
+.command('init [source_dir]')
+.description('Create files and folders based on contents of SUMMARY.md')
+.action(function(dir) {
+    dir = dir || process.cwd();
+    return initDir(dir);
+});
+
 // Parse and fallback to help if no args
 if(_.isEmpty(prog.parse(process.argv).args) && process.argv.length === 2) {
     prog.help();

lib/generate/fs.js

@@ -51,4 +51,9 @@ module.exports = {
     copy: Q.denodeify(fsExtra.copy),
     remove: Q.denodeify(fsExtra.remove),
     symlink: Q.denodeify(fsExtra.symlink),
+    exists: function(path) {
+        var d = Q.defer();
+        fs.exists(path, d.resolve);
+        return d.promise;
+    },
 };

lib/generate/init.js

@@ -0,0 +1,69 @@
+var Q = require('q');
+var _ = require('lodash');
+
+var path = require('path');
+
+var fs = require('./fs');
+var parse = require('../parse');
+
+
+// Extract paths out of a summary
+function paths(summary) {
+    return _.reduce(summary.chapters, function(accu, chapter) {
+        return accu.concat(
+            _.filter([chapter.path].concat(_.pluck(chapter.articles, 'path')))
+        );
+    }, []);
+}
+
+// Get the parent folders out of a group of files
+function folders(files) {
+    return _.chain(files)
+    .map(function(file) {
+        return path.dirname(file);
+    })
+    .uniq()
+    .value();
+}
+
+function initDir(dir) {
+    return fs.readFile(path.join(dir, 'SUMMARY.md'), 'utf8')
+    .then(function(src) {
+        // Parse summary
+        return parse.summary(src);
+    })
+    .then(function(summary) {
+        // Extract paths from summary
+        return paths(summary);
+    })
+    .then(function(paths) {
+        // Convert to absolute paths
+        return _.map(paths, function(file) {
+            return path.resolve(file);
+        });
+    })
+    .then(function(files) {
+        // Create folders
+        return Q.all(_.map(folders(files), function(folder) {
+            return fs.mkdirp(folder);
+        }))
+        .then(_.constant(files));
+    })
+    .then(function(files) {
+        // Create files that don't exist
+        return Q.all(_.map(files, function(file) {
+            return fs.exists(file)
+            .then(function(exists) {
+                if(exists) return;
+                return fs.writeFile(file, '');
+            });
+        }));
+    })
+    .fail(function(err) {
+        console.error(err.stack);
+    });
+}
+
+
+// Exports
+module.exports = initDir;