/****************************************************************************
Copyright (c) 2009, Radon Labs GmbH
Copyright (c) 2011-2013,WebJet Business Division,CYOU
 
http://www.genesis-3d.com.cn

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
****************************************************************************/
#include "stdneb.h"
#include "io/util/bxmlloaderutil.h"
#include "util/string.h"

namespace IO
{
using namespace Util;

//------------------------------------------------------------------------------
/**
*/
BXmlLoaderUtil::BXmlLoaderUtil() :
    buffer(0),
    bufSize(0),
    header(0),
    attrs(0),
    nodes(0),
    curNodeIndex(InvalidNodeIndex)
{
    // empty
}

//------------------------------------------------------------------------------
/**
*/
BXmlLoaderUtil::~BXmlLoaderUtil()
{
    // we don't own the buffer memory, so we don't free anything
}

//------------------------------------------------------------------------------
/**
*/
void
BXmlLoaderUtil::SetupFromFileInMemory(void* buf, SizeT size)
{
    n_assert(!this->IsValid());
    n_assert(0 != buf);
    n_assert(size_t(size) > sizeof(BXMLFileHeader));
    this->buffer = buf;
    this->bufSize = size;

    // setup pointers into buffer
    ubyte* ubPtr = (ubyte*) buf;
    this->header = (BXMLFileHeader*) ubPtr;
    n_assert(this->header->magic == 'BXML');
    n_assert(this->header->numStrings > 0);

    ubPtr += sizeof(BXMLFileHeader);

    this->attrs = (BXMLFileAttr*) ubPtr;    
    ubPtr += sizeof(BXMLFileAttr) * this->header->numAttrs;

    this->nodes = (BXMLFileNode*) ubPtr;
    ubPtr += sizeof(BXMLFileNode) * this->header->numNodes;

    // setup string table
    this->stringTable.Reserve(this->header->numStrings);
    uint i;
    for (i = 0; i < this->header->numStrings; i++)
    {
        this->stringTable.Append((const char*)ubPtr);
        ubPtr += String::StrLen((const char*)ubPtr) + 1;
    }

    // set current node index to root node
    this->curNodeIndex = 0;
}

//------------------------------------------------------------------------------
/**
*/
void
BXmlLoaderUtil::Discard()
{
    n_assert(this->IsValid());
    
    // NOTE: we don't own the buffer, so don't free it
    this->buffer = 0;
    this->bufSize = 0;
    this->header = 0;
    this->attrs = 0;
    this->nodes = 0;
    this->stringTable.Clear();
    this->curNodeIndex = InvalidNodeIndex;
}

//------------------------------------------------------------------------------
/**
    NOTE: childName may be 0 or point to an empty string
*/
ushort
BXmlLoaderUtil::FindChildNodeIndex(ushort nodeIndex, const char* childName) const
{
    n_assert((nodeIndex < this->header->numNodes) && (0 != childName));
    ushort childNodeIndex = this->nodes[nodeIndex].firstChildIndex;
    if (InvalidNodeIndex != childNodeIndex) do
    {
        const char* curChildName = this->stringTable[this->nodes[childNodeIndex].nameIndex];
        if ((0 == childName[0]) || (0 == String::StrCmp(curChildName, childName)))
        {
            return childNodeIndex;
        }
        childNodeIndex = this->nodes[childNodeIndex].nextSiblingIndex;
    }
    while (InvalidNodeIndex != childNodeIndex);
    
    // fallthrough: not found
    return InvalidNodeIndex;
}

//------------------------------------------------------------------------------
/**
    NOTE: childName may be 0 or point to an empty string
*/
ushort
BXmlLoaderUtil::FindSiblingNodeIndex(ushort nodeIndex, const char* sibName) const
{
    n_assert((nodeIndex < this->header->numNodes) && (0 != sibName));
    ushort sibNodeIndex = this->nodes[nodeIndex].nextSiblingIndex;
    if (InvalidNodeIndex != sibNodeIndex) do
    {
        const char* curSibName = this->stringTable[this->nodes[sibNodeIndex].nameIndex];
        if ((0 == sibName[0]) || (0 == String::StrCmp(curSibName, sibName)))
        {
            return sibNodeIndex;
        }
        sibNodeIndex = this->nodes[sibNodeIndex].nextSiblingIndex;
    }
    while (InvalidNodeIndex != sibNodeIndex);
    
    // fallthrough: not found
    return InvalidNodeIndex;
}

//------------------------------------------------------------------------------
/**
*/
ushort
BXmlLoaderUtil::GetParentNodeIndex(ushort nodeIndex) const
{
    n_assert(nodeIndex < this->header->numNodes);
    return this->nodes[nodeIndex].parentIndex;
}

//------------------------------------------------------------------------------
/**
*/
const char*
BXmlLoaderUtil::GetNodeName(ushort nodeIndex) const
{
    n_assert(nodeIndex < this->header->numNodes);
    return this->stringTable[this->nodes[nodeIndex].nameIndex];
}

//------------------------------------------------------------------------------
/**
*/
ushort
BXmlLoaderUtil::FindNodeIndex(const char* path) const
{
    n_assert(0 != path);
    
    // find the starting node index
    bool isAbsPath = (path[0] == '/');
    ushort nodeIndex;
    if (isAbsPath)
    {
        nodeIndex = 0;
    }
    else
    {
        nodeIndex = this->curNodeIndex;
    }

    // shortcut if path is not actually a path but a single node name
    if (0 == String::StrChr(path, '/'))
    {
        return this->FindChildNodeIndex(nodeIndex, path);
    }
    else
    {
        // if really a path, need to split into path tokens
        Array<String> tokens = String(path).Tokenize("/");

        // check if root node is valid
        if (isAbsPath && (tokens[0] != this->stringTable[this->nodes[0].nameIndex]))
        {
            return InvalidNodeIndex;
        }
        IndexT i = isAbsPath ? 1 : 0;
        SizeT num = tokens.Size();
        for (; i < num; i++)
        {
            const String& curToken = tokens[i];
            if (curToken == ".")
            {
                // do nothing
            }
            else if (curToken == "..")
            {
                // go to parent directory
                nodeIndex = this->nodes[nodeIndex].parentIndex;
                if (InvalidNodeIndex == nodeIndex)
                {
                    n_error("BXmlLoaderUtil::FindNode(%s): path points above root node!", path);
                    return InvalidNodeIndex;
                }
            }
            else
            {
                nodeIndex = this->FindChildNodeIndex(nodeIndex, curToken.AsCharPtr());
                if (InvalidNodeIndex == nodeIndex)
                {
                    return InvalidNodeIndex;
                }
            }
        }
        return nodeIndex;
    }
}

//------------------------------------------------------------------------------
/**
*/
bool
BXmlLoaderUtil::SetToFirstChild(const char* name)
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    ushort index = this->FindChildNodeIndex(this->curNodeIndex, name);
    if (InvalidNodeIndex != index)
    {
        this->curNodeIndex = index;
        return true;
    }
    else
    {
        return false;
    }
}

//------------------------------------------------------------------------------
/**
*/
bool
BXmlLoaderUtil::SetToNextChild(const char* name)
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    ushort index = this->FindSiblingNodeIndex(this->curNodeIndex, name);
    if (InvalidNodeIndex != index)
    {
        this->curNodeIndex = index;
        return true;
    }
    else
    {
        this->SetToParent();
        return false;
    }
}

//------------------------------------------------------------------------------
/**
*/
bool
BXmlLoaderUtil::SetToParent()
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    ushort index = this->nodes[this->curNodeIndex].parentIndex;
    if (InvalidNodeIndex != index)
    {
        this->curNodeIndex = index;
        return true;
    }
    else
    {
        return false;
    }
}

//------------------------------------------------------------------------------
/**
    Returns a local attribute index by name, this is NOT an index
    into the global attributes array!
*/
uint
BXmlLoaderUtil::FindAttrIndex(const char* attrName) const
{
    n_assert((0 != attrName) && (InvalidNodeIndex != this->curNodeIndex));
    uint firstAttrIndex = this->nodes[this->curNodeIndex].attrIndex;
    uint numAttrs = this->nodes[this->curNodeIndex].numAttrs;
    uint i;
    for (i = 0; i < numAttrs; i++)
    {
        const char* curAttrName = this->stringTable[this->attrs[firstAttrIndex + i].nameIndex];
        if (0 == String::StrCmp(curAttrName, attrName))
        {
            return i;
        }
    }
    // fallthrough: not found
    return InvalidAttrIndex;
}

//------------------------------------------------------------------------------
/**
*/
uint
BXmlLoaderUtil::GetNumAttrs() const
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    return this->nodes[this->curNodeIndex].numAttrs;
}

//------------------------------------------------------------------------------
/**
*/
const char*
BXmlLoaderUtil::GetAttrName(uint attrIndex) const
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    uint globalAttrIndex = this->nodes[this->curNodeIndex].attrIndex + attrIndex;
    return this->stringTable[this->attrs[globalAttrIndex].nameIndex];
}

//------------------------------------------------------------------------------
/**
*/
const char*
BXmlLoaderUtil::GetAttrValue(uint attrIndex) const
{
    n_assert(InvalidNodeIndex != this->curNodeIndex);
    uint globalAttrIndex = this->nodes[this->curNodeIndex].attrIndex + attrIndex;
    return this->stringTable[this->attrs[globalAttrIndex].valueIndex];
}

} // namespace IO