src/smartxml/transformations.js

   1 define(function(require) {
   2
   3 'use strict';
   4
   5 var _ = require('libs/underscore'),
   6     toret = {};
   7
   8 var getTransDesc = function(desc) {
   9     if(typeof desc === 'function') {
  10         desc = {impl: desc};
  11     }
  12     if(!desc.impl) {
  13         throw new Error('Got transformation description without implementation.');
  14     }
  15     return desc;
  16 };
  17
  18 toret.createGenericTransformation = function(desc, name) {
  19     desc = getTransDesc(desc);
  20
  21     var GenericTransformation = function(document, args) {
  22         this.args = args || [];
  23
  24         var transformation = this;
  25         // _.keys(this.args).forEach(function(key) {
  26         //     if(transformation.args[key].nodeType) { //@@ change to instanceof check, fix circular dependency
  27         //         var value = transformation.args[key],
  28         //             path = value.getPath();
  29         //         Object.defineProperty(transformation.args, key, {
  30         //             get: function() {
  31         //                 if(transformation.hasRun) {
  32         //                     //console.log('returning via path');
  33         //                     return transformation.document.getNodeByPath(path);
  34         //                 } else {
  35         //                     //console.log('returning original arg');
  36         //                     return value;
  37
  38         //                 }
  39         //             }
  40         //         });
  41         //     }
  42         // });
  43
  44         // potem spr na dotychczasowych undo/redo tests;
  45
  46
  47         this.args.forEach(function(arg, idx, args) {
  48             var path;
  49             if(arg) {
  50                 if(arg.nodeType) { // ~
  51                     path = arg.getPath();
  52                     Object.defineProperty(args, idx, {
  53                         get: function() {
  54                             if(transformation.hasRun && path) {
  55                                 return transformation.document.getNodeByPath(path);
  56                             } else {
  57                                 return arg;
  58                             }
  59                         }
  60                     });
  61                 } else if(_.isObject(arg)) {
  62                     _.keys(arg).forEach(function(key) {
  63                         var value = arg[key],
  64                             path;
  65                         if(value && value.nodeType) {
  66                             path = value.getPath();
  67                             Object.defineProperty(arg, key, {
  68                                 get: function() {
  69                                     if(transformation.hasRun && path) {
  70                                         return transformation.document.getNodeByPath(path);
  71                                     } else {
  72                                         return value;
  73                                     }
  74                                 }
  75                             });
  76                         }
  77                     });
  78                 }
  79             }
  80         });
  81
  82         this.document = document;
  83         this.hasRun = false;
  84         if(desc.init) {
  85             desc.init.call(this);
  86         }
  87     };
  88     _.extend(GenericTransformation.prototype, {
  89         name: name,
  90         run: function(options) {
  91             var changeRoot;
  92             if(!desc.undo && options.beUndoable) {
  93                 changeRoot = this.getChangeRoot();
  94                 if(!changeRoot) {
  95                      throw new Error(
  96                          'Transformation {name} returned invalid change root value'
  97                          .replace('{name}', name)
  98                      );
  99                 }
 100                 this.changeRootPath = changeRoot.getPath();
 101                 this.snapshot = changeRoot.clone();
 102             }
 103             var argsToPass = desc.undo ? [this].concat(this.args) : this.args;
 104             var toret = desc.impl.apply(this.context, argsToPass);
 105             this.hasRun = true;
 106             return toret;
 107         },
 108         undo: function() {
 109             if(desc.undo) {
 110                 desc.undo.call(this.context, this);
 111             } else {
 112                 this.document.getNodeByPath(this.changeRootPath).replaceWith(this.snapshot);
 113             }
 114         },
 115         getChangeRoot: desc.getChangeRoot || function() {
 116             return this.document.root;
 117         }
 118     });
 119
 120     return GenericTransformation;
 121 };
 122
 123 toret.createContextTransformation = function(desc, name) {
 124     var GenericTransformation = toret.createGenericTransformation(desc, name);
 125
 126     var ContextTransformation = function(document, object, args) {
 127         GenericTransformation.call(this, document, args);
 128
 129         if(document === object) {
 130             this.context = document;
 131         } else {
 132             var contextPath = object.getPath(),
 133                 transformation = this;
 134             Object.defineProperty(this, 'context', {
 135                 get: function() {
 136                     if(transformation.hasRun) {
 137                         return transformation.document.getNodeByPath(contextPath);
 138                     } else {
 139                         return object;
 140                     }
 141                 }
 142             });
 143         }
 144     };
 145     ContextTransformation.prototype = Object.create(GenericTransformation.prototype);
 146     return ContextTransformation;
 147 };
 148
 149 return toret;
 150
 151 });