gecko/content/xul/templates/src/nsTreeRows.h

471 lines
13 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Chris Waterson <waterson@netscape.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsTreeRows_h__
#define nsTreeRows_h__
#include "nsCOMPtr.h"
#include "nsTArray.h"
#include "pldhash.h"
#include "nsIXULTemplateResult.h"
#include "nsTemplateMatch.h"
#include "nsIRDFResource.h"
/**
* This class maintains the state of the XUL tree builder's
* rows. It maps a row number to the nsTemplateMatch object that
* populates the row.
*/
class nsTreeRows
{
public:
class iterator;
friend class iterator;
enum Direction { eDirection_Forwards = +1, eDirection_Backwards = -1 };
enum ContainerType {
eContainerType_Unknown = 0,
eContainerType_Noncontainer = 1,
eContainerType_Container = 2
};
enum ContainerState {
eContainerState_Unknown = 0,
eContainerState_Open = 1,
eContainerState_Closed = 2
};
enum ContainerFill {
eContainerFill_Unknown = 0,
eContainerFill_Empty = 1,
eContainerFill_Nonempty = 2
};
class Subtree;
/**
* A row in the tree. Contains the match that the row
* corresponds to, and a pointer to the row's subtree, if there
* are any.
*/
struct Row {
nsTemplateMatch* mMatch;
ContainerType mContainerType : 4;
ContainerState mContainerState : 4;
ContainerFill mContainerFill : 4;
Subtree* mSubtree; // XXX eventually move to hashtable
};
/**
* A subtree in the tree. A subtree contains rows, which may
* contain other subtrees.
*/
class Subtree {
protected:
friend class nsTreeRows; // so that it can access members, for now
/**
* The parent subtree; null if we're the root
*/
Subtree* mParent;
/**
* The number of immediate children in this subtree
*/
PRInt32 mCount;
/**
* The capacity of the subtree
*/
PRInt32 mCapacity;
/**
* The total number of rows in this subtree, recursively
* including child subtrees.
*/
PRInt32 mSubtreeSize;
/**
* The array of rows in the subtree
*/
Row* mRows;
public:
/**
* Creates a subtree with the specified parent.
*/
Subtree(Subtree* aParent)
: mParent(aParent),
mCount(0),
mCapacity(0),
mSubtreeSize(0),
mRows(nsnull) {}
~Subtree();
/**
* Return the number of immediate child rows in the subtree
*/
PRInt32 Count() const { return mCount; }
/**
* Return the number of rows in this subtree, as well as all
* the subtrees it contains.
*/
PRInt32 GetSubtreeSize() const { return mSubtreeSize; }
/**
* Retrieve the immediate child row at the specified index.
*/
const Row& operator[](PRInt32 aIndex) const {
NS_PRECONDITION(aIndex >= 0 && aIndex < mCount, "bad index");
return mRows[aIndex]; }
/**
* Retrieve the immediate row at the specified index.
*/
Row& operator[](PRInt32 aIndex) {
NS_PRECONDITION(aIndex >= 0 && aIndex < mCount, "bad index");
return mRows[aIndex]; }
/**
* Remove all rows from the subtree.
*/
void Clear();
protected:
/**
* Insert an immediate child row at the specified index.
*/
iterator InsertRowAt(nsTemplateMatch* aMatch, PRInt32 aIndex);
/**
* Remove an immediate child row from the specified index.
*/
void RemoveRowAt(PRInt32 aChildIndex);
};
friend class Subtree;
protected:
/**
* A link in the path through the view's tree.
*/
struct Link {
Subtree* mParent;
PRInt32 mChildIndex;
Link&
operator=(const Link& aLink) {
mParent = aLink.mParent;
mChildIndex = aLink.mChildIndex;
return *this; }
PRBool
operator==(const Link& aLink) const {
return (mParent == aLink.mParent)
&& (mChildIndex == aLink.mChildIndex); }
Subtree* GetParent() { return mParent; }
const Subtree* GetParent() const { return mParent; }
PRInt32 GetChildIndex() const { return mChildIndex; }
Row& GetRow() { return (*mParent)[mChildIndex]; }
const Row& GetRow() const { return (*mParent)[mChildIndex]; }
};
public:
/**
* An iterator that can be used to traverse the tree view.
*/
class iterator {
protected:
PRInt32 mRowIndex;
nsAutoTArray<Link, 8> mLink;
void Next();
void Prev();
friend class Subtree; // so InsertRowAt can initialize us
friend class nsTreeRows; // so nsTreeRows can initialize us
/**
* Used by operator[]() to initialize an iterator.
*/
void Append(Subtree* aParent, PRInt32 aChildIndex);
/**
* Used by InsertRowAt() to initialize an iterator.
*/
void Push(Subtree *aParent, PRInt32 aChildIndex);
/**
* Used by operator[]() and InsertRowAt() to initialize an iterator.
*/
void SetRowIndex(PRInt32 aRowIndex) { mRowIndex = aRowIndex; }
/**
* Handy accessors to the top element.
*/
Link& GetTop() { return mLink[mLink.Length() - 1]; }
const Link& GetTop() const { return mLink[mLink.Length() - 1]; }
public:
iterator() : mRowIndex(-1) {}
iterator(const iterator& aIterator);
iterator& operator=(const iterator& aIterator);
PRBool operator==(const iterator& aIterator) const;
PRBool operator!=(const iterator& aIterator) const {
return !aIterator.operator==(*this); }
const Row& operator*() const { return GetTop().GetRow(); }
Row& operator*() { return GetTop().GetRow(); }
const Row* operator->() const { return &(GetTop().GetRow()); }
Row* operator->() { return &(GetTop().GetRow()); }
iterator& operator++() { Next(); return *this; }
iterator operator++(int) { iterator temp(*this); Next(); return temp; }
iterator& operator--() { Prev(); return *this; }
iterator operator--(int) { iterator temp(*this); Prev(); return temp; }
/**
* Return the current parent link
*/
Subtree* GetParent() { return GetTop().GetParent(); }
const Subtree* GetParent() const { return GetTop().GetParent(); }
/**
* Return the current child index
*/
PRInt32 GetChildIndex() const { return GetTop().GetChildIndex(); }
/**
* Return the depth of the path the iterator is maintaining
* into the tree.
*/
PRInt32 GetDepth() const { return mLink.Length(); }
/**
* Return the current row index of the iterator
*/
PRInt32 GetRowIndex() const { return mRowIndex; }
/**
* Pop the iterator up a level.
*/
iterator& Pop() { mLink.SetLength(GetDepth() - 1); return *this; }
};
/**
* Retrieve the first element in the view
*/
iterator First();
/**
* Retrieve (one past) the last element in the view
*/
iterator Last();
/**
* Find the row that contains the given resource
*/
iterator FindByResource(nsIRDFResource* aResource);
/**
* Find the row that contains the result
*/
iterator Find(nsIXULTemplateResult* aResult);
/**
* Retrieve the ith element in the view
*/
iterator operator[](PRInt32 aIndex);
nsTreeRows() : mRoot(nsnull) {}
~nsTreeRows() {}
/**
* Ensure that a child subtree exists within the specified parent
* at the specified child index within the parent. (In other
* words, create a subtree if one doesn't already exist.)
*/
Subtree*
EnsureSubtreeFor(Subtree* aParent, PRInt32 aChildIndex);
/**
* Ensure that a child subtree exists at the iterator's position.
*/
Subtree*
EnsureSubtreeFor(iterator& aIterator) {
return EnsureSubtreeFor(aIterator.GetParent(),
aIterator.GetChildIndex()); }
/**
* Get the child subtree for the specified parent at the specified
* child index. Optionally return the child subtree's size. Will
* return `null' if no subtree exists.
*/
Subtree*
GetSubtreeFor(const Subtree* aParent,
PRInt32 aChildIndex,
PRInt32* aSubtreeSize = nsnull);
/**
* Retrieve the size of the subtree within the specified parent.
*/
PRInt32
GetSubtreeSizeFor(const Subtree* aParent,
PRInt32 aChildIndex) {
PRInt32 size;
GetSubtreeFor(aParent, aChildIndex, &size);
return size; }
/**
* Retrieve the size of the subtree within the specified parent.
*/
PRInt32
GetSubtreeSizeFor(const iterator& aIterator) {
PRInt32 size;
GetSubtreeFor(aIterator.GetParent(), aIterator.GetChildIndex(), &size);
return size; }
/**
* Remove the specified subtree for a row, leaving the row itself
* intact.
*/
void
RemoveSubtreeFor(Subtree* aParent, PRInt32 aChildIndex);
/**
* Remove the specified subtree for a row, leaving the row itself
* intact.
*/
void
RemoveSubtreeFor(iterator& aIterator) {
RemoveSubtreeFor(aIterator.GetParent(), aIterator.GetChildIndex()); }
/**
* Remove the specified row from the view
*/
PRInt32
RemoveRowAt(iterator& aIterator) {
iterator temp = aIterator--;
Subtree* parent = temp.GetParent();
parent->RemoveRowAt(temp.GetChildIndex());
InvalidateCachedRow();
return parent->Count(); }
/**
* Insert a new match into the view
*/
iterator
InsertRowAt(nsTemplateMatch* aMatch, Subtree* aSubtree, PRInt32 aChildIndex) {
InvalidateCachedRow();
return aSubtree->InsertRowAt(aMatch, aChildIndex); }
/**
* Raw access to the rows; e.g., for sorting.
*/
Row*
GetRowsFor(Subtree* aSubtree) { return aSubtree->mRows; }
/**
* Remove all of the rows
*/
void Clear();
/**
* Return the total number of rows in the tree view.
*/
PRInt32 Count() const { return mRoot.GetSubtreeSize(); }
/**
* Retrieve the root subtree
*/
Subtree* GetRoot() { return &mRoot; }
/**
* Set the root resource for the view
*/
void SetRootResource(nsIRDFResource* aResource) {
mRootResource = aResource; }
/**
* Retrieve the root resource for the view
*/
nsIRDFResource* GetRootResource() {
return mRootResource.get(); }
/**
* Invalidate the cached row; e.g., because the view has changed
* in a way that would corrupt the iterator.
*/
void
InvalidateCachedRow() { mLastRow = iterator(); }
protected:
/**
* The root subtree.
*/
Subtree mRoot;
/**
* The root resource for the view
*/
nsCOMPtr<nsIRDFResource> mRootResource;
/**
* The last row that was asked for by operator[]. By remembering
* this, we can usually avoid the O(n) search through the row
* array to find the row at the specified index.
*/
iterator mLastRow;
};
#endif // nsTreeRows_h__