/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2009 Torus Knot Software Ltd

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 "OgreStableHeaders.h"
#include "OgreScriptParser.h"
#include "OgreException.h"


namespace Ogre
{

	ScriptParser::ScriptParser()
	{
	}

	ConcreteNodeListPtr ScriptParser::parse(const ScriptTokenListPtr &tokens)
	{
		// MEMCATEGORY_GENERAL because SharedPtr can only free using that category
		ConcreteNodeListPtr nodes(OGRE_NEW_T(ConcreteNodeList, MEMCATEGORY_GENERAL)(), SPFM_DELETE_T);

		enum{READY, OBJECT};
		uint32 state = READY;

		ConcreteNode *parent = 0;
		ConcreteNodePtr node;
		ScriptToken *token = 0;
		ScriptTokenList::iterator i = tokens->begin(), end = tokens->end();
		while(i != end)
		{
			token = (*i).get();

			switch(state)
			{
			case READY:
				if(token->type == TID_WORD)
				{
					if(token->lexeme == "import")
					{
						node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						node->token = token->lexeme;
						node->file = token->file;
						node->line = token->line;
						node->type = CNT_IMPORT;

						// The next token is the target
						++i;
						if(i == end || ((*i)->type != TID_WORD && (*i)->type != TID_QUOTE))
							OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
								Ogre::String("expected import target at line ") + 
									Ogre::StringConverter::toString(node->line),
								"ScriptParser::parse");
						ConcreteNodePtr temp(OGRE_NEW ConcreteNode());
						temp->parent = node.get();
						temp->file = (*i)->file;
						temp->line = (*i)->line;
						temp->type = (*i)->type == TID_WORD ? CNT_WORD : CNT_QUOTE;
						if(temp->type == CNT_QUOTE)
							temp->token = (*i)->lexeme.substr(1, token->lexeme.size() - 2);
						else
							temp->token = (*i)->lexeme;
						node->children.push_back(temp);

						// The second-next token is the source
						++i;
						++i;
						if(i == end || ((*i)->type != TID_WORD && (*i)->type != TID_QUOTE))
							OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
								Ogre::String("expected import source at line ") + 
									Ogre::StringConverter::toString(node->line),
								"ScriptParser::parse");
						temp = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						temp->parent = node.get();
						temp->file = (*i)->file;
						temp->line = (*i)->line;
						temp->type = (*i)->type == TID_WORD ? CNT_WORD : CNT_QUOTE;
						if(temp->type == CNT_QUOTE)
							temp->token = (*i)->lexeme.substr(1, (*i)->lexeme.size() - 2);
						else
							temp->token = (*i)->lexeme;
						node->children.push_back(temp);

						// Consume all the newlines
						i = skipNewlines(i, end);

						// Insert the node
						if(parent)
						{
							node->parent = parent;
							parent->children.push_back(node);
						}
						else
						{
							node->parent = 0;
							nodes->push_back(node);
						}
						node = ConcreteNodePtr();
					}
					else if(token->lexeme == "set")
					{
						node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						node->token = token->lexeme;
						node->file = token->file;
						node->line = token->line;
						node->type = CNT_VARIABLE_ASSIGN;

						// The next token is the variable
						++i;
						if(i == end || (*i)->type != TID_VARIABLE)
							OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
								Ogre::String("expected variable name at line ") + 
									Ogre::StringConverter::toString(node->line),
								"ScriptParser::parse");
						ConcreteNodePtr temp(OGRE_NEW ConcreteNode());
						temp->parent = node.get();
						temp->file = (*i)->file;
						temp->line = (*i)->line;
						temp->type = CNT_VARIABLE;
						temp->token = (*i)->lexeme;
						node->children.push_back(temp);

						// The next token is the assignment
						++i;
						if(i == end || ((*i)->type != TID_WORD && (*i)->type != TID_QUOTE))
							OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
								Ogre::String("expected variable value at line ") + 
									Ogre::StringConverter::toString(node->line),
								"ScriptParser::parse");
						temp = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						temp->parent = node.get();
						temp->file = (*i)->file;
						temp->line = (*i)->line;
						temp->type = (*i)->type == TID_WORD ? CNT_WORD : CNT_QUOTE;
						if(temp->type == CNT_QUOTE)
							temp->token = (*i)->lexeme.substr(1, (*i)->lexeme.size() - 2);
						else
							temp->token = (*i)->lexeme;
						node->children.push_back(temp);

						// Consume all the newlines
						i = skipNewlines(i, end);

						// Insert the node
						if(parent)
						{
							node->parent = parent;
							parent->children.push_back(node);
						}
						else
						{
							node->parent = 0;
							nodes->push_back(node);
						}
						node = ConcreteNodePtr();
					}
					else
					{
						node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						node->file = token->file;
						node->line = token->line;
						node->type = token->type == TID_WORD ? CNT_WORD : CNT_QUOTE;
						if(node->type == CNT_QUOTE)
							node->token = token->lexeme.substr(1, token->lexeme.size() - 2);
						else
							node->token = token->lexeme;

						// Insert the node
						if(parent)
						{
							node->parent = parent;
							parent->children.push_back(node);
						}
						else
						{
							node->parent = 0;
							nodes->push_back(node);
						}

						// Set the parent
						parent = node.get();

						// Switch states
						state = OBJECT;

						node = ConcreteNodePtr();
					}
				}
				else if(token->type == TID_RBRACKET)
				{
					// Go up one level if we can
					if(parent)
						parent = parent->parent;

					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_RBRACE;

					// Consume all the newlines
					i = skipNewlines(i, end);

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}

					// Move up another level
					if(parent)
						parent = parent->parent;

					node = ConcreteNodePtr();
				}
				break;
			case OBJECT:
				if(token->type == TID_NEWLINE)
				{
					// Look ahead to the next non-newline token and if it isn't an {, this was a property
					ScriptTokenList::iterator next = skipNewlines(i, end);
					if(next == end || (*next)->type != TID_LBRACKET)
					{
						// Ended a property here
						if(parent)
							parent = parent->parent;
						state = READY;
					}
				}
				else if(token->type == TID_COLON)
				{
					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_COLON;

					// The following token are the parent objects (base classes).
                    // Require at least one of them.

					ScriptTokenList::iterator j = i + 1;
					j = skipNewlines(j, end);
					if(j == end || ((*j)->type != TID_WORD && (*j)->type != TID_QUOTE)) {
						OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
							Ogre::String("expected object identifier at line ") + 
                                    Ogre::StringConverter::toString(node->line),
							"ScriptParser::parse");
                    }

					while(j != end && ((*j)->type == TID_WORD || (*j)->type == TID_QUOTE))
					{
						ConcreteNodePtr tempNode = ConcreteNodePtr(OGRE_NEW ConcreteNode());
						tempNode->token = (*j)->lexeme;
						tempNode->file = (*j)->file;
						tempNode->line = (*j)->line;
						tempNode->type = (*j)->type == TID_WORD ? CNT_WORD : CNT_QUOTE;
						tempNode->parent = node.get();
						node->children.push_back(tempNode);
						++j;
					}

					// Move it backwards once, since the end of the loop moves it forwards again anyway
					j--;
					i = j;

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}
					node = ConcreteNodePtr();
				}
				else if(token->type == TID_LBRACKET)
				{
					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_LBRACE;

					// Consume all the newlines
					i = skipNewlines(i, end);

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}

					// Set the parent
					parent = node.get();

					// Change the state
					state = READY;

					node = ConcreteNodePtr();
				}
				else if(token->type == TID_RBRACKET)
				{
					// Go up one level if we can
					if(parent)
						parent = parent->parent;

					// If the parent is currently a { then go up again
					if(parent && parent->type == CNT_LBRACE && parent->parent)
						parent = parent->parent;

					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_RBRACE;

					// Consume all the newlines
					i = skipNewlines(i, end);

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}

					// Move up another level
					if(parent)
						parent = parent->parent;

					node = ConcreteNodePtr();
					state = READY;
				}
				else if(token->type == TID_VARIABLE)
				{
					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_VARIABLE;

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}
					node = ConcreteNodePtr();
				}
				else if(token->type == TID_QUOTE)
				{
					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme.substr(1, token->lexeme.size() - 2);
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_QUOTE;

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}
					node = ConcreteNodePtr();
				}
				else if(token->type == TID_WORD)
				{
					node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
					node->token = token->lexeme;
					node->file = token->file;
					node->line = token->line;
					node->type = CNT_WORD;

					// Insert the node
					if(parent)
					{
						node->parent = parent;
						parent->children.push_back(node);
					}
					else
					{
						node->parent = 0;
						nodes->push_back(node);
					}
					node = ConcreteNodePtr();
				}
				break;
			}

			++i;
		}

		return nodes;
	}

	ConcreteNodeListPtr ScriptParser::parseChunk(const ScriptTokenListPtr &tokens)
	{
		// MEMCATEGORY_GENERAL because SharedPtr can only free using that category
		ConcreteNodeListPtr nodes(OGRE_NEW_T(ConcreteNodeList, MEMCATEGORY_GENERAL)(), SPFM_DELETE_T);

		ConcreteNodePtr node;
		ScriptToken *token = 0;
		for(ScriptTokenList::const_iterator i = tokens->begin(); i != tokens->end(); ++i)
		{
			token = (*i).get();

			switch(token->type)
			{
			case TID_VARIABLE:
				node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
				node->file = token->file;
				node->line = token->line;
				node->parent = 0;
				node->token = token->lexeme;
				node->type = CNT_VARIABLE;
				break;
			case TID_WORD:
				node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
				node->file = token->file;
				node->line = token->line;
				node->parent = 0;
				node->token = token->lexeme;
				node->type = CNT_WORD;
				break;
			case TID_QUOTE:
				node = ConcreteNodePtr(OGRE_NEW ConcreteNode());
				node->file = token->file;
				node->line = token->line;
				node->parent = 0;
				node->token = token->lexeme.substr(1, token->lexeme.size() - 2);
				node->type = CNT_QUOTE;
			default:
				OGRE_EXCEPT(Exception::ERR_INVALID_STATE, 
					Ogre::String("unexpected token") + token->lexeme + " at line " + 
						Ogre::StringConverter::toString(token->line),
					"ScriptParser::parseChunk");
			}

			if(!node.isNull())
				nodes->push_back(node);
		}

		return nodes;
	}

	ScriptToken *ScriptParser::getToken(ScriptTokenList::iterator i, ScriptTokenList::iterator end, int offset)
	{
		ScriptToken *token = 0;
		ScriptTokenList::iterator iter = i + offset;
		if(iter != end)
			token = (*i).get();
		return token;
	}

	ScriptTokenList::iterator ScriptParser::skipNewlines(ScriptTokenList::iterator i, ScriptTokenList::iterator end)
	{
		while(i != end && (*i)->type == TID_NEWLINE)
			++i;
		return i;
	}

}