mediawiki-extensions-Visual.../modules/es/es.TransactionProcessor.js

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/**
* Creates an es.TransactionProcessor object.
*
* @class
* @constructor
*/
es.TransactionProcessor = function( model, transaction ) {
this.model = model;
this.transaction = transaction;
this.cursor = 0;
this.set = [];
this.clear = [];
};
/* Static Members */
es.TransactionProcessor.operationMap = {
// Retain
'retain': {
'commit': function( op ) {
this.retain( op );
},
'rollback': function( op ) {
this.retain( op );
}
},
// Insert
'insert': {
'commit': function( op ) {
this.insert( op );
},
'rollback': function( op ) {
this.remove( op );
}
},
// Remove
'remove': {
'commit': function( op ) {
this.remove( op );
},
'rollback': function( op ) {
this.insert( op );
}
},
// Change element attributes
'attribute': {
'commit': function( op ) {
this.attribute( op, false );
},
'rollback': function( op ) {
this.attribute( op, true );
}
},
// Change content annotations
'annotate': {
'commit': function( op ) {
this.mark( op, false );
},
'rollback': function( op ) {
this.mark( op, true );
}
}
};
/* Static Methods */
es.TransactionProcessor.commit = function( doc, transaction ) {
var tp = new es.TransactionProcessor( doc, transaction );
tp.process( 'commit' );
};
es.TransactionProcessor.rollback = function( doc, transaction ) {
var tp = new es.TransactionProcessor( doc, transaction );
tp.process( 'rollback' );
};
/* Methods */
es.TransactionProcessor.prototype.process = function( method ) {
var operations = this.transaction.getOperations();
for ( var i = 0, length = operations.length; i < length; i++ ) {
var operation = operations[i];
if ( operation.type in es.TransactionProcessor.operationMap ) {
es.TransactionProcessor.operationMap[operation.type][method].call( this, operation );
} else {
throw 'Invalid operation error. Operation type is not supported: ' + operation.type;
}
}
};
// TODO: document this. Various arguments are optional or nonoptional in different cases, that's confusing
// so it needs to be documented well.
es.TransactionProcessor.prototype.rebuildNodes = function( newData, oldNodes, parent, index ) {
var newNodes = es.DocumentModel.createNodesFromData( newData ),
remove = 0;
if ( oldNodes ) {
// Determine parent and index if not given
if ( oldNodes[0] === oldNodes[0].getRoot() ) {
// We know the values for parent and index in this case
// and don't have to compute them. Override any parent
// or index parameter passed.
parent = oldNodes[0];
index = 0;
remove = parent.getChildren().length;
} else {
parent = parent || oldNodes[0].getParent();
index = index || parent.indexOf( oldNodes[0] );
remove = oldNodes.length;
}
// Try to preserve the first node
if (
// There must be an old and new node to preserve
newNodes.length &&
oldNodes.length &&
// Node types need to match
newNodes[0].type === oldNodes[0].type &&
// Only for leaf nodes
!newNodes[0].hasChildren()
) {
var newNode = newNodes.shift(),
oldNode = oldNodes.shift();
// Let's just leave this first node in place and adjust it's length
var newAttributes = newNode.getElement().attributes,
oldAttributes = oldNode.getElement().attributes;
if ( oldAttributes || newAttributes ) {
oldNode.getElement().attributes = newAttributes;
}
oldNode.adjustContentLength( newNode.getContentLength() - oldNode.getContentLength() );
index++;
remove--;
}
}
// Try to perform this in a single operation if possible, this reduces the number of UI updates
// TODO: Introduce a global for max argument length - 1024 is also assumed in es.insertIntoArray
if ( newNodes.length < 1024 ) {
parent.splice.apply( parent, [index, remove].concat( newNodes ) );
} else if ( newNodes.length ) {
parent.splice.apply( parent, [index, remove] );
// Safe to call with arbitrary length of newNodes
es.insertIntoArray( parent, index, newNodes );
}
};
/**
* Get the parent node that would be affected by inserting given data into it's child.
*
* This is used when inserting data that closes and reopens one or more parent nodes into a child
* node, which requires rebuilding at a higher level.
*
* @method
* @param {es.DocumentNode} node Child node to start from
* @param {Array} data Data to inspect for closings
* @returns {es.DocumentNode} Lowest level parent node being affected
*/
es.TransactionProcessor.prototype.getScope = function( node, data ) {
var i,
length,
level = 0,
max = 0;
for ( i = 0, length = data.length; i < length; i++ ) {
if ( typeof data[i].type === 'string' ) {
level += data[i].type.charAt( 0 ) === '/' ? 1 : -1;
max = Math.max( max, level );
}
}
if ( max > 0 ) {
for ( i = 0; i < max - 1; i++ ) {
node = node.getParent();
}
}
return node;
};
es.TransactionProcessor.prototype.applyAnnotations = function( to, update ) {
var i,
j,
k,
length,
annotation,
changes = 0,
index;
// Handle annotations
if ( this.set.length ) {
for ( i = 0, length = this.set.length; i < length; i++ ) {
annotation = this.set[i];
// Auto-build annotation hash
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getHash( annotation );
}
for ( j = this.cursor; j < to; j++ ) {
// Auto-convert to array
if ( es.isArray( this.model.data[j] ) ) {
this.model.data[j].push( annotation );
} else {
this.model.data[j] = [this.model.data[j], annotation];
}
}
}
changes++;
}
if ( this.clear.length ) {
for ( i = 0, length = this.clear.length; i < length; i++ ) {
annotation = this.clear[i];
if ( annotation instanceof RegExp ) {
for ( j = this.cursor; j < to; j++ ) {
var matches = es.DocumentModel.getMatchingAnnotations(
this.model.data[j], annotation
);
for ( k = 0; k < matches.length; k++ ) {
index = this.model.data[j].indexOf( matches[k] );
if ( index !== -1 ) {
this.model.data[j].splice( index, 1 );
}
}
// Auto-convert to string
if ( this.model.data[j].length === 1 ) {
this.model.data[j] = this.model.data[j][0];
}
}
} else {
// Auto-build annotation hash
if ( annotation.hash === undefined ) {
annotation.hash = es.DocumentModel.getHash( annotation );
}
for ( j = this.cursor; j < to; j++ ) {
index = es.DocumentModel.getIndexOfAnnotation(
this.model.data[j], annotation
);
if ( index !== -1 ) {
this.model.data[j].splice( index, 1 );
}
// Auto-convert to string
if ( this.model.data[j].length === 1 ) {
this.model.data[j] = this.model.data[j][0];
}
}
}
}
changes++;
}
if ( update && changes ) {
var fromNode = this.model.getNodeFromOffset( this.cursor ),
toNode = this.model.getNodeFromOffset( to );
this.model.traverseLeafNodes( function( node ) {
node.emit( 'update' );
if ( node === toNode ) {
return false;
}
}, fromNode );
}
};
es.TransactionProcessor.prototype.retain = function( op ) {
this.applyAnnotations( this.cursor + op.length, true );
this.cursor += op.length;
};
es.TransactionProcessor.prototype.insert = function( op ) {
var node,
index,
offset;
if ( es.DocumentModel.isStructuralOffset( this.model.data, this.cursor ) ) {
es.insertIntoArray( this.model.data, this.cursor, op.data );
this.applyAnnotations( this.cursor + op.data.length );
node = this.model.getNodeFromOffset( this.cursor );
offset = this.model.getOffsetFromNode( node );
index = node.getIndexFromOffset( this.cursor - offset );
this.rebuildNodes( op.data, null, node, index );
} else {
node = this.model.getNodeFromOffset( this.cursor );
if ( node.getParent() === this.model ) {
offset = this.model.getOffsetFromNode( node );
} else {
node = this.getScope( node, op.data );
offset = this.model.getOffsetFromNode( node );
}
if ( es.DocumentModel.containsElementData( op.data ) ) {
// Perform insert on linear data model
es.insertIntoArray( this.model.data, this.cursor, op.data );
this.applyAnnotations( this.cursor + op.data.length );
// Synchronize model tree
if ( offset === -1 ) {
throw 'Invalid offset error. Node is not in model tree';
}
this.rebuildNodes(
this.model.data.slice( offset, offset + node.getElementLength() + op.data.length ),
[node]
);
} else {
// Perform insert on linear data model
// TODO this is duplicated from above
es.insertIntoArray( this.model.data, this.cursor, op.data );
this.applyAnnotations( this.cursor + op.data.length );
// Update model tree
node.adjustContentLength( op.data.length, true );
node.emit( 'update', this.cursor - offset );
}
}
this.cursor += op.data.length;
};
es.TransactionProcessor.prototype.remove = function( op ) {
if ( es.DocumentModel.containsElementData( op.data ) ) {
// Figure out which nodes are covered by the removal
var ranges = this.model.selectNodes( new es.Range( this.cursor, this.cursor + op.data.length ) );
// Build the list of nodes to rebuild and the data to keep
var oldNodes = [], newData = [], parent = null, index = null, firstKeptNode, lastKeptNode;
for ( var i = 0; i < ranges.length; i++ ) {
oldNodes.push( ranges[i].node );
if ( ranges[i].range !== undefined ) {
// We have to keep part of this node
if ( firstKeptNode === undefined ) {
// This is the first node we're keeping
firstKeptNode = ranges[i].node;
}
// Compute the start and end offset of this node
// We could do that with getOffsetFromNode() but
// we already have all the numbers we need so why would we
var startOffset = ranges[i].globalRange.start - ranges[i].range.start,
endOffset = startOffset + ranges[i].node.getContentLength(),
// Get this node's data
nodeData = this.model.data.slice( startOffset, endOffset );
// Remove data covered by the range from nodeData
nodeData.splice( ranges[i].range.start, ranges[i].range.end - ranges[i].range.start );
// What remains in nodeData is the data we need to keep
// Append it to newData
newData = newData.concat( nodeData );
lastKeptNode = ranges[i].node;
}
}
// Surround newData with the right openings and closings if needed
if ( firstKeptNode !== undefined ) {
// There are a number of conceptually different cases here,
// but the algorithm for dealing with them is the same.
// 1. Removal within one node: firstKeptNode === lastKeptNode
// 2. Merge of siblings: firstKeptNode.getParent() === lastKeptNode.getParent()
// 3. Merge of arbitrary depth: firstKeptNode and lastKeptNode have a common ancestor
// Because #1 and #2 are special cases of #3 (merges with depth=0 and depth=1, respectively),
// the code below that deals with the general case (#3) and automatically covers
// #1 and #2 that way as well.
// Simultaneously traverse upwards from firstKeptNode and lastKeptNode
// to find the common ancestor. On our way up, keep the element of each
// node we visit and verify that the transaction is a valid merge (i.e. it satisfies
// the merge criteria in prepareRemoval()'s canMerge()).
// FIXME: The code is essentially the same as canMerge(), merge these algorithms
var openings = [], closings = [],
paths = es.DocumentNode.getCommonAncestorPaths( firstKeptNode, lastKeptNode ),
i, prevN1, prevN2;
if ( !paths ) {
throw 'Removal is not a valid merge: nodes do not have a common ancestor or are not at the same depth';
}
for ( i = 0; i < paths.node1Path.length; i++ ) {
// Verify the element types are equal
if ( paths.node1Path[i].getElementType() !== paths.node2Path[i].getElementType() ) {
throw 'Removal is not a valid merge: corresponding parents have different types ( ' +
paths.node1Path[i].getElementType() + ' vs ' + paths.node2Path[i].getElementType() + ' )';
}
// Record the opening of n1 and the closing of n2
openings.push( paths.node1Path[i].getElement() );
closings.push( { 'type': '/' + paths.node2Path[i].getElementType() } );
}
// Surround newData with the openings and closings
newData = openings.reverse().concat( newData, closings );
// Rebuild oldNodes if needed
// This only happens for merges with depth > 1
prevN1 = paths.node1Path.length ? paths.node1Path[paths.node1Path.length - 1] : null;
prevN2 = paths.node2Path.length ? paths.node2Path[paths.node2Path.length - 1] : null;
if ( prevN1 && prevN1 !== oldNodes[0] ) {
oldNodes = [ prevN1 ];
parent = paths.commonAncestor;
index = parent.indexOf( prevN1 ); // Pass to rebuildNodes() so it's not recomputed
if ( index === -1 ) {
throw "Tree corruption detected: node isn't in its parent's children array";
}
var foundPrevN2 = false;
for ( var j = index + 1; !foundPrevN2 && j < parent.getChildren().length; j++ ) {
oldNodes.push( parent.getChildren()[j] );
foundPrevN2 = parent.getChildren()[j] === prevN2;
}
if ( !foundPrevN2 ) {
throw "Tree corruption detected: node isn't in its parent's children array";
}
}
}
// Update the linear model
this.model.data.splice( this.cursor, op.data.length );
// Perform the rebuild. This updates the model tree
this.rebuildNodes( newData, oldNodes, parent, index );
} else {
// We're removing content only. Take a shortcut
// Get the node we are removing content from
var node = this.model.getNodeFromOffset( this.cursor );
// Update model tree
node.adjustContentLength( -op.data.length, true );
// Update the linear model
this.model.data.splice( this.cursor, op.data.length );
// Emit an update so things sync up
var offset = this.model.getOffsetFromNode( node );
node.emit( 'update', this.cursor - offset );
}
};
es.TransactionProcessor.prototype.attribute = function( op, invert ) {
var element = this.model.data[this.cursor];
if ( element.type === undefined ) {
throw 'Invalid element error. Can not set attributes on non-element data.';
}
if ( ( op.method === 'set' && !invert ) || ( op.method === 'clear' && invert ) ) {
// Automatically initialize attributes object
if ( !element.attributes ) {
element.attributes = {};
}
element.attributes[op.key] = op.value;
} else if ( ( op.method === 'clear' && !invert ) || ( op.method === 'set' && invert ) ) {
if ( element.attributes ) {
delete element.attributes[op.key];
}
// Automatically clean up attributes object
var empty = true;
for ( var key in element.attributes ) {
empty = false;
break;
}
if ( empty ) {
delete element.attributes;
}
} else {
throw 'Invalid method error. Can not operate attributes this way: ' + method;
}
};
es.TransactionProcessor.prototype.mark = function( op, invert ) {
var target;
if ( ( op.method === 'set' && !invert ) || ( op.method === 'clear' && invert ) ) {
target = this.set;
} else if ( ( op.method === 'clear' && !invert ) || ( op.method === 'set' && invert ) ) {
target = this.clear;
} else {
throw 'Invalid method error. Can not operate attributes this way: ' + method;
}
if ( op.bias === 'start' ) {
target.push( op.annotation );
} else if ( op.bias === 'stop' ) {
var index;
if ( op.annotation instanceof RegExp ) {
index = target.indexOf( op.annotation );
} else {
index = es.DocumentModel.getIndexOfAnnotation( target, op.annotation );
}
if ( index === -1 ) {
throw 'Annotation stack error. Annotation is missing.';
}
target.splice( index, 1 );
}
};