First commit

utils/db-mixins.js

@@ -0,0 +1,86 @@
+(function(root) {
+
+  var _ = root._ || require('underscore');
+
+  if (!root._) {
+    _.mixin(require('underscore.inflections'));
+  }
+  
+  function get(db, table, id) {
+    return _.find(db[table], function (row) {
+      return row.id === id  
+    });
+  }
+
+  function exist(db, table, id) {
+    return !_.isUndefined(_.get(db, table, id));
+  }
+
+  function createId(db, table) {
+    if (_.isEmpty(db[table])) {
+      return 1;
+    } else {
+      return _.max(db[table], function(row) {
+        return row.id;
+      }).id + 1;
+    }
+  }
+
+  function create(db, table, obj) {
+    var clone = _.clone(obj);
+
+    if (_.isUndefined(clone.id)) clone.id = _.createId(db, table);
+
+    db[table].push(clone);
+
+    return clone;
+  }
+
+  function update(db, table, id, attrs) {
+    var row = get(db, table, id),
+        updatedRow = _.extend(row, attrs),
+        index = _.indexOf(db[table], row);
+      
+    db[table][index] = updatedRow;
+  }
+
+  function clean(db) {
+    var toBeRemoved = [];
+
+    _(db).each(function(table, tableName) {
+      _(table).each(function(row) {
+        _(row).each(function(value, key) {
+          if (/Id$/.test(key)) {
+            var reference = _.pluralize(key.slice(0, - 2));
+            if (!_.exist(db, reference, row[key])) {
+              toBeRemoved.push({
+                tableName: tableName, 
+                id: row.id
+              });
+            }
+          }
+        });
+      });
+    });
+
+    _(toBeRemoved).each(function(row) {
+      _.remove(db, row.tableName, row.id);
+    });
+  }
+
+  function remove(db, table, id) {
+    var newTable = _.reject(db[table], function(row) {
+        return row.id === id;
+    });
+
+    db[table] = newTable;
+  }
+
+  _.get = get;
+  _.exist = exist;
+  _.createId = createId;
+  _.create = create;
+  _.update = update;
+  _.clean = clean;
+  _.remove = remove;
+})(this);