/**
 * @file llxmlnode.h
 * @brief LLXMLNode definition
 *
 * $LicenseInfo:firstyear=2000&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLXMLNODE_H
#define LL_LLXMLNODE_H

#ifndef XML_STATIC
#define XML_STATIC
#endif
#ifdef LL_USESYSTEMLIBS
#include <expat.h>
#else
#include "expat/expat.h"
#endif
#include <map>

#include "indra_constants.h"
#include "llrefcount.h"
#include "llpointer.h"
#include "llstring.h"
#include "llstringtable.h"
#include "llfile.h"
#include "lluuid.h"

class LLVector3;
class LLVector3d;
class LLQuaternion;
class LLColor4;
class LLColor4U;
class LLSD;


struct CompareAttributes
{
    bool operator()(const LLStringTableEntry* const lhs, const LLStringTableEntry* const rhs) const
    {
        if (lhs == NULL)
            return true;
        if (rhs == NULL)
            return true;

        return strcmp(lhs->mString, rhs->mString) < 0;
    }
};


// Defines a simple node hierarchy for reading and writing task objects

class LLXMLNode;
typedef LLPointer<LLXMLNode> LLXMLNodePtr;
typedef std::multimap<std::string, LLXMLNodePtr > LLXMLNodeList;
typedef std::multimap<const LLStringTableEntry *, LLXMLNodePtr > LLXMLChildList;
typedef std::map<const LLStringTableEntry *, LLXMLNodePtr, CompareAttributes> LLXMLAttribList;

class LLColor4;
class LLColor4U;
class LLQuaternion;
class LLVector3;
class LLVector3d;
class LLVector4;
class LLVector4U;

struct LLXMLChildren : public LLThreadSafeRefCount
{
    LLXMLChildList map;         // Map of children names->pointers
    LLXMLNodePtr head;          // Head of the double-linked list
    LLXMLNodePtr tail;          // Tail of the double-linked list
};
typedef LLPointer<LLXMLChildren> LLXMLChildrenPtr;

class LLXMLNode : public LLThreadSafeRefCount
{
public:
    enum ValueType
    {
        TYPE_CONTAINER,     // A node which contains nodes
        TYPE_UNKNOWN,       // A node loaded from file without a specified type
        TYPE_BOOLEAN,       // "true" or "false"
        TYPE_INTEGER,       // any integer type: U8, U32, S32, U64, etc.
        TYPE_FLOAT,         // any floating point type: F32, F64
        TYPE_STRING,        // a string
        TYPE_UUID,          // a UUID
        TYPE_NODEREF,       // the ID of another node in the hierarchy to reference
    };

    enum Encoding
    {
        ENCODING_DEFAULT = 0,
        ENCODING_DECIMAL,
        ENCODING_HEX,
        // ENCODING_BASE32, // Not implemented yet
    };

protected:
    ~LLXMLNode();

public:
    LLXMLNode();
    LLXMLNode(const char* name, bool is_attribute);
    LLXMLNode(LLStringTableEntry* name, bool is_attribute);
    LLXMLNode(const LLXMLNode& rhs);
    LLXMLNodePtr deepCopy();

    bool isNull();

    bool deleteChild(LLXMLNode* child);
    void addChild(LLXMLNodePtr& new_child);
    void setParent(LLXMLNodePtr& new_parent); // reparent if necessary

    // Deserialization
    static bool parseFile(
        const std::string& filename,
        LLXMLNodePtr& node,
        LLXMLNode* defaults = nullptr);
    static bool parseBuffer(
        const char* buffer,
        U64 length,
        LLXMLNodePtr& node,
        LLXMLNode* defaults = nullptr);
    static bool parseStream(
        std::istream& str,
        LLXMLNodePtr& node,
        LLXMLNode* defaults = nullptr);
    static bool updateNode(
        LLXMLNodePtr& node,
        LLXMLNodePtr& update_node);

    static bool getLayeredXMLNode(LLXMLNodePtr& root, const std::vector<std::string>& paths);


    // Write standard XML file header:
    // <?xml version="1.0" encoding="utf-8" standalone="yes" ?>
    static void writeHeaderToFile(LLFILE *out_file);

    // Write XML to file with one attribute per line.
    // XML escapes values as they are written.
    void writeToFile(LLFILE *out_file, const std::string& indent = std::string(), bool use_type_decorations=true);
    void writeToOstream(std::ostream& output_stream, const std::string& indent = std::string(), bool use_type_decorations=true);

    // Utility
    void findName(const std::string& name, LLXMLNodeList &results);
    void findName(LLStringTableEntry* name, LLXMLNodeList &results);
    void findID(const std::string& id, LLXMLNodeList &results);


    virtual LLXMLNodePtr createChild(const char* name, bool is_attribute);
    virtual LLXMLNodePtr createChild(LLStringTableEntry* name, bool is_attribute);


    // Getters
    U32 getBoolValue(U32 expected_length, bool *array);
    U32 getByteValue(U32 expected_length, U8 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getIntValue(U32 expected_length, S32 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getUnsignedValue(U32 expected_length, U32 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getLongValue(U32 expected_length, U64 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getFloatValue(U32 expected_length, F32 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getDoubleValue(U32 expected_length, F64 *array, Encoding encoding = ENCODING_DEFAULT);
    U32 getStringValue(U32 expected_length, std::string *array);
    U32 getUUIDValue(U32 expected_length, LLUUID *array);
    U32 getNodeRefValue(U32 expected_length, LLXMLNode **array);

    bool hasAttribute(const char* name );

    bool getAttributeBOOL(const char* name, bool& value );
    bool getAttributeU8(const char* name, U8& value );
    bool getAttributeS8(const char* name, S8& value );
    bool getAttributeU16(const char* name, U16& value );
    bool getAttributeS16(const char* name, S16& value );
    bool getAttributeU32(const char* name, U32& value );
    bool getAttributeS32(const char* name, S32& value );
    bool getAttributeF32(const char* name, F32& value );
    bool getAttributeF64(const char* name, F64& value );
    bool getAttributeColor(const char* name, LLColor4& value );
    bool getAttributeColor4(const char* name, LLColor4& value );
    bool getAttributeColor4U(const char* name, LLColor4U& value );
    bool getAttributeVector3(const char* name, LLVector3& value );
    bool getAttributeVector3d(const char* name, LLVector3d& value );
    bool getAttributeQuat(const char* name, LLQuaternion& value );
    bool getAttributeUUID(const char* name, LLUUID& value );
    bool getAttributeString(const char* name, std::string& value );

    const ValueType& getType() const { return mType; }
    U32 getLength() const { return mLength; }
    U32 getPrecision() const { return mPrecision; }
    const std::string& getValue() const { return mValue; }
    std::string getSanitizedValue() const;
    std::string getTextContents() const;
    const LLStringTableEntry* getName() const { return mName; }
    bool hasName(const char* name) const { return mName == gStringTable.checkStringEntry(name); }
    bool hasName(const std::string& name) const { return mName == gStringTable.checkStringEntry(name.c_str()); }
    const std::string& getID() const { return mID; }

    U32 getChildCount() const;
    // getChild returns a Null LLXMLNode (not a NULL pointer) if there is no such child.
    // This child has no value so any getTYPEValue() calls on it will return 0.
    bool getChild(const char* name, LLXMLNodePtr& node, bool use_default_if_missing = true);
    bool getChild(const LLStringTableEntry* name, LLXMLNodePtr& node, bool use_default_if_missing = true);
    void getChildren(const char* name, LLXMLNodeList &children, bool use_default_if_missing = true) const;
    void getChildren(const LLStringTableEntry* name, LLXMLNodeList &children, bool use_default_if_missing = true) const;

    // recursively finds all children at any level matching name
    void getDescendants(const LLStringTableEntry* name, LLXMLNodeList &children) const;

    bool getAttribute(const char* name, LLXMLNodePtr& node, bool use_default_if_missing = true);
    bool getAttribute(const LLStringTableEntry* name, LLXMLNodePtr& node, bool use_default_if_missing = true);

    S32 getLineNumber();

    // The following skip over attributes
    LLXMLNodePtr getFirstChild() const;
    LLXMLNodePtr getNextSibling() const;

    LLXMLNodePtr getRoot();

    // Setters

    bool setAttributeString(const char* attr, const std::string& value);

    void setBoolValue(const bool value) { setBoolValue(1, &value); }
    void setByteValue(const U8 value, Encoding encoding = ENCODING_DEFAULT) { setByteValue(1, &value, encoding); }
    void setIntValue(const S32 value, Encoding encoding = ENCODING_DEFAULT) { setIntValue(1, &value, encoding); }
    void setUnsignedValue(const U32 value, Encoding encoding = ENCODING_DEFAULT) { setUnsignedValue(1, &value, encoding); }
    void setLongValue(const U64 value, Encoding encoding = ENCODING_DEFAULT) { setLongValue(1, &value, encoding); }
    void setFloatValue(const F32 value, Encoding encoding = ENCODING_DEFAULT, U32 precision = 0) { setFloatValue(1, &value, encoding); }
    void setDoubleValue(const F64 value, Encoding encoding = ENCODING_DEFAULT, U32 precision = 0) { setDoubleValue(1, &value, encoding); }
    void setStringValue(const std::string& value) { setStringValue(1, &value); }
    void setUUIDValue(const LLUUID value) { setUUIDValue(1, &value); }
    void setNodeRefValue(const LLXMLNode *value) { setNodeRefValue(1, &value); }

    void setBoolValue(U32 length, const bool *array);
    void setByteValue(U32 length, const U8 *array, Encoding encoding = ENCODING_DEFAULT);
    void setIntValue(U32 length, const S32 *array, Encoding encoding = ENCODING_DEFAULT);
    void setUnsignedValue(U32 length, const U32* array, Encoding encoding = ENCODING_DEFAULT);
    void setLongValue(U32 length, const U64 *array, Encoding encoding = ENCODING_DEFAULT);
    void setFloatValue(U32 length, const F32 *array, Encoding encoding = ENCODING_DEFAULT, U32 precision = 0);
    void setDoubleValue(U32 length, const F64 *array, Encoding encoding = ENCODING_DEFAULT, U32 precision = 0);
    void setStringValue(U32 length, const std::string *array);
    void setUUIDValue(U32 length, const LLUUID *array);
    void setNodeRefValue(U32 length, const LLXMLNode **array);
    void setValue(const std::string& value);
    void setName(const std::string& name);
    void setName(LLStringTableEntry* name);

    void setLineNumber(S32 line_number);

    // Escapes " (quot) ' (apos) & (amp) < (lt) > (gt)
    static std::string escapeXML(const std::string& xml);

    // Set the default node corresponding to this default node
    void setDefault(LLXMLNode *default_node);

    // Find the node within defaults_list which corresponds to this node
    void findDefault(LLXMLNode *defaults_list);

    void updateDefault();

    // Delete any child nodes that aren't among the tree's children, recursive
    void scrubToTree(LLXMLNode *tree);

    bool deleteChildren(const std::string& name);
    bool deleteChildren(LLStringTableEntry* name);
    void setAttributes(ValueType type, U32 precision, Encoding encoding, U32 length);
//  void appendValue(const std::string& value); // Unused

    bool fromXMLRPCValue(LLSD& target);

    // Unit Testing
    void createUnitTest(S32 max_num_children);
    bool performUnitTest(std::string &error_buffer);

protected:
    bool removeChild(LLXMLNode* child);
    bool isFullyDefault();

    bool parseXmlRpcArrayValue(LLSD& target);
    bool parseXmlRpcStructValue(LLSD& target);

public:
    std::string mID;                // The ID attribute of this node

    XML_Parser *mParser;        // Temporary pointer while loading

    bool mIsAttribute;          // Flag is only used for output formatting
    U32 mVersionMajor;          // Version of this tag to use
    U32 mVersionMinor;
    U32 mLength;                // If the length is nonzero, then only return arrays of this length
    U32 mPrecision;             // The number of BITS per array item
    ValueType mType;            // The value type
    Encoding mEncoding;         // The value encoding
    S32 mLineNumber;            // line number in source file, if applicable

    LLXMLNode* mParent;             // The parent node
    LLXMLChildrenPtr mChildren;     // The child nodes
    LLXMLAttribList mAttributes;        // The attribute nodes
    LLXMLNodePtr mPrev;             // Double-linked list previous node
    LLXMLNodePtr mNext;             // Double-linked list next node

    static bool sStripEscapedStrings;
    static bool sStripWhitespaceValues;

protected:
    LLStringTableEntry *mName;      // The name of this node

    // The value of this node (use getters/setters only)
    // Values are not XML-escaped in memory
    // They may contain " (quot) ' (apos) & (amp) < (lt) > (gt)
    std::string mValue;

    LLXMLNodePtr mDefault;      // Mirror node in the default tree

    static const char *skipWhitespace(const char *str);
    static const char *skipNonWhitespace(const char *str);
    static const char *parseInteger(const char *str, U64 *dest, bool *is_negative, U32 precision, Encoding encoding);
    static const char *parseFloat(const char *str, F64 *dest, U32 precision, Encoding encoding);
};

#endif // LL_LLXMLNODE