#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include "cpdf.h"
#include "parse.h"
#include "utils.h"
/* function compute number of locations of char c from buffer to character c 
 */
int strlenc(char *buffer, char c, char to)
{
	int i = 0;
	while (*buffer && *buffer != to) {
		if (*buffer == c)
			i++;
		buffer++;
	}
	return i;
}

/* function compute lenght of string to char to
 */
int strlento(char *buffer, char to)
{
	int i = 0;
	while (*buffer && *buffer != to) {
		i++;
		buffer++;
	}
	return i;
}

/* convert hex to bin
 */
char *hex(char *buffer)
{
	char *hex_array, *end;
	char num[5] = { '0', 'x', '\0', '\0', '\0' };
	int i;
	if (*buffer != '<')
		return NULL;
	if ((i = strlento(buffer + 1, '>') >> 1) == 0)
		return NULL;
	end = hex_array = (char *) xmalloc(i);
	for (buffer++; *buffer != '>'; hex_array++) {
		num[2] = *buffer;
		if (*(buffer + 1) == '>') {
			num[3] = '0';
			buffer++;
		} else {
			num[3] = *(buffer + 1);
			buffer += 2;
		}
		*hex_array = (char) strtoul((char *) &num, NULL, 16);
	}
	return end;
}

/* interpreter for special characters in name string */
char *name(char *buffer)
{
	char *ret, *end;
	char num[5] = { '0', 'x', '\0', '\0', '\0' };
	if (*buffer != '/')
		return NULL;
	if (memchr(buffer, '#', MAXNAMELEN) == NULL)
		return buffer;
	end = ret = (char *) xmalloc(MAXNAMELEN);
	while (*buffer && *buffer != ' ') {
		if (*buffer == '#') {
			num[2] = *(buffer + 1);
			num[3] = *(buffer + 2);
			*ret = (char) strtoul((char *) &num, NULL, 16);
			ret++;
			buffer += 3;
		}
		*ret = *buffer;
		ret++;
		buffer++;
	}
	return end;
}

/* parse arrays */
char **array(char *buffer)
{
	char **ret = NULL;
	int end = 1, len, index = 0;
	if (*buffer != '[')
		return NULL;
	ret[index] = (char *) xmalloc(1);
	*ret[index] = '[';
	index++;
	buffer += 2;
	do {
		if (*buffer == ']')
			end--;
		if (*buffer == '[')
			end++;
		len = strlento(buffer, ' ');
		ret[index] = (char *) xmalloc(len);
		strncpy(ret[index], buffer, len);
		buffer += len + 1;
		index++;
	} while (end > 0);
	return ret;
}

#define BUFLEN 255
void read_obj(long offset)
{
	char buffer[BUFLEN];
	int obj_num, size = 0;
	struct object *obj =
	    (struct object *) xcalloc(sizeof(struct object), 1);
	fseek(fp, offset, SEEK_SET);
	fget(buffer, BUFLEN, fp);
	sscanf(buffer, "%d ", &obj_num);
	fget(buffer, BUFLEN, fp);
	while (!strstr(buffer, "endobj")) {
		size += strlen(buffer) + 1;
		obj->unparsed = resize(obj->unparsed, size);
		strcat(obj->unparsed, buffer);
		fget(buffer, BUFLEN, fp);
	}
	object[obj_num] = obj;
	return;
}

/*	obj->type = UNKNOWN;
	obj->obj = NULL;
	if(!strstr(&buffer[0],"<<")) {
		obj->type = NOTYPE;
		obj->obj = fill_data(); 
	}
	while (buffer[0] != '>' && buffer[1] != '>'
	       && obj->type == UNKNOWN) {
		if (!strncmp(&buffer[0], "/Type", 5)) {
			if (!strncmp(&buffer[7], "Page", 4)) {
				obj->type = PAGE;
			}
			if (!strncmp(&buffer[7], "Pages", 5)) {
				obj->type = PAGES;
			}
			if (!strncmp(&buffer[7], "Catalog", 7)) {
				obj->type = CATALOG;
			}
			if (!strncmp(&buffer[7], "Encoding", 8)) {
				obj->type = ENCODING;
			}
			if (!strncmp(&buffer[7], "XObject", 7)) {
				obj->type = XOBJECT;
			}
		}
		if (!strncmp(&buffer[0], "/Font", 5)) {
			obj->type = FONT;
		}
		if (!strncmp(&buffer[0], "stream", 7)) {
			obj->type = CONTENT;
		}
		fget(&buffer[0], BUFLEN, fp);
	}*/

void add_obj(char *s)
{
	long offset, old_off;
	sscanf(s, "%ld ", &offset);
	old_off = ftell(fp);
	read_obj(offset);
	fseek(fp, old_off, SEEK_SET);
}

/* find objects */
void xref(void)
{
	char xref[XREFLINE];
	long offset = 0;
	int i = XREFLINE - 2;
	xref[XREFLINE - 1] = '\0';
	fstat(fp->_fileno, &fpstat);
	offset = fpstat.st_size - 8;
	fseek(fp, offset, SEEK_SET);
	while (1) {
		xref[i] = fgetc(fp);
		if (xref[i] == '\r' || xref[i] == '\n')
			break;
		i--;
		offset--;
		fseek(fp, offset, SEEK_SET);
	}
	offset = strtoul(&xref[i + 1], NULL, 10);
	fseek(fp, offset, SEEK_SET);
	fget(&xref[0], XREFLINE, fp);
	if (strstr(&xref[0], "xref") == NULL) {
		/* error */
		return;
	}
	fget(&xref[0], XREFLINE, fp);
	{
		int entry[2];
		sscanf(&xref[0], "%d %d", &entry[0], &entry[1]);
		object = (struct object **) xmalloc(entry[0] + entry[1]);
		if (!entry[0])
			fseek(fp, 20, SEEK_CUR);
		fget(&xref[0], XREFLINE, fp);
		while (strncmp(&xref[0], "trailer", 5)) {
			add_obj(&xref[0]);
			fget(&xref[0], XREFLINE, fp);
		}
	}
	return;
}

int parse_pdf(void)
{
	xref();
	return 0;
}