/*
	This file is part of Warzone 2100.
	Copyright (C) 1999-2004  Eidos Interactive
	Copyright (C) 2005-2007  Warzone Resurrection Project

	Warzone 2100 is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	Warzone 2100 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 General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with Warzone 2100; if not, write to the Free Software
	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
 * StrRes.c
 *
 * String storage an manipulation functions
 *
 */

#include <string.h>
#include <stdlib.h>

/* Allow frame header files to be singly included */
#define FRAME_LIB_INCLUDE

#include "types.h"
#include "debug.h"
#include "treap.h"
#include "strres.h"
#include "strresly.h"

/* A string block */
typedef struct STR_BLOCK
{
	char	**apStrings;
	UDWORD	idStart, idEnd;

#ifdef DEBUG_CHECK_FOR_UNUSED_STRINGS
	unsigned int*   aUsage;
#endif

	struct STR_BLOCK* psNext;
} STR_BLOCK;

/* An ID entry */
typedef struct STR_ID
{
	UDWORD	id;
	char	*pIDStr;
} STR_ID;

/* A String Resource */
typedef struct STR_RES
{
	struct TREAP_NODE**     psIDTreap;              ///< The treap to store string identifiers
	STR_BLOCK*              psStrings;              ///< The store for the strings themselves
	size_t                  init, ext;              ///< Sizes for the string blocks
	UDWORD                  nextID;                 ///< The next free ID
} STR_RES;

/* Static forward declarations */
static void strresReleaseIDStrings(STR_RES *psRes);

/* Allocate a string block */
static STR_BLOCK* strresAllocBlock(const size_t size)
{
	STR_BLOCK* const psBlock = (STR_BLOCK*)malloc(sizeof(*psBlock));
	if (!psBlock)
	{
		debug(LOG_ERROR, "Out of memory - 1");
		abort();
		return NULL;
	}

	psBlock->apStrings = (char**)calloc(size, sizeof(*psBlock->apStrings));
	if (!psBlock->apStrings)
	{
		debug(LOG_ERROR, "Out of memory - 2");
		abort();
		free(psBlock);
		return NULL;
	}

#ifdef DEBUG_CHECK_FOR_UNUSED_STRINGS
	psBlock->aUsage = (unsigned int*)calloc(size, sizeof(*psBlock->aUsage));
	if (!psBlock->aUsage)
	{
		debug(LOG_ERROR, "Out of memory - 3");
		abort();
		free(psBlock->apStrings);
		free(psBlock);
		return NULL;
	}
#endif

	return psBlock;
}


/* Initialise the string system */
STR_RES* strresCreate(size_t init, size_t ext)
{
	STR_RES* const psRes = (STR_RES*)malloc(sizeof(*psRes));
	if (!psRes)
	{
		debug(LOG_ERROR, "Out of memory");
		abort();
		return NULL;
	}
	psRes->init = init;
	psRes->ext = ext;
	psRes->nextID = 0;

	psRes->psIDTreap = treapCreate();
	if (!psRes->psIDTreap)
	{
		debug(LOG_ERROR, "Out of memory");
		abort();
		free(psRes);
		return NULL;
	}

	psRes->psStrings = strresAllocBlock(init);
	if (!psRes->psStrings)
	{
		treapDestroy(psRes->psIDTreap);
		free(psRes);
		return NULL;
	}
	psRes->psStrings->psNext = NULL;
	psRes->psStrings->idStart = 0;
	psRes->psStrings->idEnd = init-1;

	return psRes;
}


/* Release the id strings, but not the strings themselves,
 * (they can be accessed only by id number).
 */
static void strresReleaseIDStrings(STR_RES *psRes)
{
	STR_ID		*psID;

	ASSERT( psRes != NULL,
		"strresReleaseIDStrings: Invalid string res pointer" );

	for(psID = treapGetSmallest(psRes->psIDTreap); psID;
		psID = treapGetSmallest(psRes->psIDTreap))
	{
		treapDel(psRes->psIDTreap, psID->pIDStr);
		free(psID->pIDStr);
		free(psID);
	}
}


/* Shutdown the string system */
void strresDestroy(STR_RES *psRes)
{
	STR_BLOCK	*psBlock, *psNext = NULL;
	UDWORD		i;

	ASSERT( psRes != NULL,
		"strresDestroy: Invalid string res pointer" );

	// Free the string id's
	strresReleaseIDStrings(psRes);

	// Free the strings themselves
	for(psBlock = psRes->psStrings; psBlock; psBlock=psNext)
	{
		for(i=psBlock->idStart; i<=psBlock->idEnd; i++)
		{
#ifdef DEBUG_CHECK_FOR_UNUSED_STRINGS
			if (psBlock->aUsage[i - psBlock->idStart] == 0
				&& i != 0 && i < psRes->nextID)
			{
 				debug( LOG_NEVER, "strresDestroy: String id %d not used:\n               \"%s\"\n", i, psBlock->apStrings[i - psBlock->idStart] );
			}
#endif
			if (psBlock->apStrings[i - psBlock->idStart])
			{
				free(psBlock->apStrings[i - psBlock->idStart]);
			}
#ifdef DEBUG
			else if (i < psRes->nextID)
			{
				debug( LOG_NEVER, "strresDestroy: No string loaded for id %d\n", i );
			}
#endif
		}
		psNext = psBlock->psNext;
		free(psBlock->apStrings);
#ifdef DEBUG_CHECK_FOR_UNUSED_STRINGS
		free(psBlock->aUsage);
#endif
		free(psBlock);
	}

	// Release the treap and free the final memory
	treapDestroy(psRes->psIDTreap);
	free(psRes);
}


/* Return the ID number for an ID string */
BOOL strresGetIDNum(STR_RES *psRes, const char *pIDStr, UDWORD *pIDNum)
{
	STR_ID	*psID;

	ASSERT( psRes != NULL,
		"strresGetIDNum: Invalid string res pointer" );

	psID = treapFind(psRes->psIDTreap, pIDStr);
	if (!psID)
	{
		*pIDNum = 0;
		return false;
	}

	*pIDNum = psID->id;

	return true;
}


/* Return the ID stored ID string that matches the string passed in */
char* strresGetIDString(STR_RES *psRes, const char *pIDStr)
{
	STR_ID *psID;

	ASSERT(psRes != NULL, "Invalid string res pointer");

	psID = treapFind(psRes->psIDTreap, pIDStr);
	if (!psID)
	{
		return NULL;
	}

	return psID->pIDStr;
}


/* Store a string */
BOOL strresStoreString(STR_RES *psRes, char *pID, const char *pString)
{
	STR_ID		*psID;
	char		*pNew;
	STR_BLOCK	*psBlock;

	ASSERT( psRes != NULL,
		"strresStoreString: Invalid string res pointer" );

	// Find the id for the string
	psID = treapFind(psRes->psIDTreap, pID);
	if (!psID)
	{
		// No ID yet so generate a new one
		psID = (STR_ID*)malloc(sizeof(*psID));
		if (!psID)
		{
			debug( LOG_ERROR, "strresStoreString: Out of memory" );
			abort();
			return false;
		}
		psID->pIDStr = strdup(pID);
		if (!psID->pIDStr)
		{
			debug( LOG_ERROR, "strresStoreString: Out of memory" );
			abort();
			free(psID);
			return false;
		}
		psID->id = psRes->nextID;
		psRes->nextID += 1;
		treapAdd(psRes->psIDTreap, psID->pIDStr, psID);
	}

	// Find the block to store the string in
	for(psBlock = psRes->psStrings; psBlock->idEnd < psID->id;
		psBlock = psBlock->psNext)
	{
		if (!psBlock->psNext)
		{
			// Need to allocate a new string block
			psBlock->psNext = strresAllocBlock(psRes->ext);
			if (!psBlock->psNext)
			{
				return false;
			}
			psBlock->psNext->idStart = psBlock->idEnd+1;
			psBlock->psNext->idEnd = psBlock->idEnd + psRes->ext;
			psBlock->psNext->psNext = NULL;
		}
	}

	// Put the new string in the string block
	if (psBlock->apStrings[psID->id - psBlock->idStart] != NULL)
	{
		debug( LOG_ERROR, "strresStoreString: Duplicate string for id: %s", psID->pIDStr );
		abort();
		return false;
	}

	// Allocate a copy of the string
	pNew = strdup(pString);
	if (!pNew)
	{
		debug( LOG_ERROR, "strresStoreString: Out of memory" );
		abort();
		return false;
	}
	psBlock->apStrings[psID->id - psBlock->idStart] = pNew;

	return true;
}


/* Get the string from an ID number */
char *strresGetString(STR_RES *psRes, UDWORD id)
{
	STR_BLOCK	*psBlock;

	ASSERT( psRes != NULL,
		"strresGetString: Invalid string res pointer" );

	// find the block the string is in
	for(psBlock = psRes->psStrings; psBlock && psBlock->idEnd < id;
		psBlock = psBlock->psNext)
	{}

	if (!psBlock)
	{
		ASSERT( false, "strresGetString: String not found" );
		// Return the default string
		return psRes->psStrings->apStrings[0];
	}

	ASSERT( psBlock->apStrings[id - psBlock->idStart] != NULL,
		"strresGetString: String not found" );

#ifdef DEBUG_CHECK_FOR_UNUSED_STRINGS
	psBlock->aUsage[id - psBlock->idStart] += 1;
#endif

	if (psBlock->apStrings[id - psBlock->idStart] == NULL)
	{
		// Return the default string
		return psRes->psStrings->apStrings[0];
	}

	return psBlock->apStrings[id - psBlock->idStart];
}


/* Load a string resource file */
BOOL strresLoad(STR_RES* psRes, const char* fileName)
{
	bool retval;
	lexerinput_t input;

	input.type = LEXINPUT_PHYSFS;
	input.input.physfsfile = PHYSFS_openRead(fileName);
	if (!input.input.physfsfile)
	{
		debug(LOG_ERROR, "strresLoadFile: PHYSFS_openRead(\"%s\") failed with error: %s\n", fileName, PHYSFS_getLastError());
		return false;
	}

	strres_set_extra(&input);
	retval = (strres_parse(psRes) == 0);

	strres_lex_destroy();
	PHYSFS_close(input.input.physfsfile);

	return retval;
}

/* Get the ID number for a string*/
UDWORD strresGetIDfromString(STR_RES *psRes, const char *pString)
{
	STR_BLOCK *psBlock, *psNext = NULL;
	unsigned int i;

	ASSERT( psRes != NULL,
		"strresGetID: Invalid string res pointer" );

	// Search through all the blocks to find the string
	for(psBlock = psRes->psStrings; psBlock != NULL; psBlock=psNext)
	{
		for(i = psBlock->idStart; i <= psBlock->idEnd; i++)
		{
			if ( psBlock->apStrings[i - psBlock->idStart] &&
				!strcmp(psBlock->apStrings[i - psBlock->idStart], pString) )
			{
				return i;
			}
		}
		psNext = psBlock->psNext;
	}
	return 0;
}