/**
 * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 **/
#include "lwip/opt.h"
#include "lwip/def.h"
#include "fs.h"
#include "fsdata.h"
#include <string.h>
#include "tm_stm32f4_ethernet.h"

/** Set this to 1 to include "fsdata_custom.c" instead of "fsdata.c" for the
 * file system (to prevent changing the file included in CVS) */
#ifndef HTTPD_USE_CUSTUM_FSDATA
#define HTTPD_USE_CUSTUM_FSDATA 0
#endif

#if HTTPD_USE_CUSTUM_FSDATA
#include "fsdata_custom.c"
#else /* HTTPD_USE_CUSTUM_FSDATA */
#include "fsdata.h"
#endif /* HTTPD_USE_CUSTUM_FSDATA */

/* Define the file system memory allocation structure. */
struct fs_table {
	struct fs_file file;
	uint8_t inuse;
};

/* Number of opened files */
static uint16_t opened_files = 0;

/* Allocate file system memory */
struct fs_table fs_memory[ETHERNET_MAX_OPEN_FILES];

/*-----------------------------------------------------------------------------------*/
static struct fs_file * fs_malloc(void) {
	int i;
	for (i = 0; i < ETHERNET_MAX_OPEN_FILES; i++) {
		if (fs_memory[i].inuse == 0) {
			fs_memory[i].inuse = 1;
			/* Set index we are */
			fs_memory[i].file.id = i;
			/* Set pointer to location */
			fs_memory[i].file.opened_files_count = &opened_files;
			return (&fs_memory[i].file);
		}
	}
	return (NULL);
}

/*-----------------------------------------------------------------------------------*/
static void fs_free(struct fs_file *file) {
	int i;
	for(i = 0; i < ETHERNET_MAX_OPEN_FILES; i++) {
		if (&fs_memory[i].file == file) {
			fs_memory[i].inuse = 0;
			break;
		}
	}
	return;
}

/*-----------------------------------------------------------------------------------*/
struct fs_file * fs_open(const char *name) {
	struct fs_file *file;
	const struct fsdata_file *f;

	file = fs_malloc();
	if (file == NULL) {
		return NULL;
	}

#if LWIP_HTTPD_CUSTOM_FILES
	if (strlen(name) < ETHERNET_SERVER_MAX_CUSTOM_FILENAME) {
		/* Call user function */
		if (TM_ETHERNETSERVER_OpenFileCallback(file, name)) {
			/* Set settings */
			file->is_custom_file = 1;
			file->http_header_included = 0;
			file->index = 0;
			file->pextension = NULL;
			
			/* Set file name */
			strcpy(file->file_name, name);

			/* Increase number of opened files */
			opened_files++;
			
			/* Return pointer */
			return file;
		}
	}

	file->is_custom_file = 0;
#endif /* LWIP_HTTPD_CUSTOM_FILES */

	for(f = FS_ROOT; f != NULL; f = f->next) {
		if (!strcmp(name, (char *)f->name)) {
			file->data = (const char *)f->data;
			file->len = f->len;
			file->index = f->len;
			file->pextension = NULL;
			file->http_header_included = f->http_header_included;
#if HTTPD_PRECALCULATED_CHECKSUM
			file->chksum_count = f->chksum_count;
			file->chksum = f->chksum;
#endif /* HTTPD_PRECALCULATED_CHECKSUM */
#if LWIP_HTTPD_FILE_STATE
			file->state = fs_state_init(file, name);
#endif /* #if LWIP_HTTPD_FILE_STATE */
			
			/* Increase number of opened files */
			opened_files++;
			
			return file;
		}
	}
	fs_free(file);
	return NULL;
}

/*-----------------------------------------------------------------------------------*/
void fs_close(struct fs_file *file) {
	/* Decrease number of opened files */
	opened_files--;
#if LWIP_HTTPD_CUSTOM_FILES
	if (file->is_custom_file) {				
		/* Call user function */
		TM_ETHERNETSERVER_CloseFileCallback(file);
	}
#endif /* LWIP_HTTPD_CUSTOM_FILES */
#if LWIP_HTTPD_FILE_STATE
	fs_state_free(file, file->state);
#endif /* #if LWIP_HTTPD_FILE_STATE */
	fs_free(file);
}
/*-----------------------------------------------------------------------------------*/
int fs_read(struct fs_file *file, char *buffer, int count) {
	int read;
#if LWIP_HTTPD_CUSTOM_FILES
		if (file->is_custom_file) {
		/* Read custom file */
		/* Call user function */
		read = TM_ETHERNETSERVER_ReadFileCallback(file, buffer, count);
		/* Increase index value */
		file->index += read;
		/* Return number of read characters */
		return read;
	}
#endif /* LWIP_HTTPD_CUSTOM_FILES */

	if (file->index == file->len) {
		return -1;
	}

	read = file->len - file->index;
	if(read > count) {
		read = count;
	}

	MEMCPY(buffer, (file->data + file->index), read);
	file->index += read;

	return(read);
}
/*-----------------------------------------------------------------------------------*/
int fs_bytes_left(struct fs_file *file) {
	return file->len - file->index;
}