//read_log() reads data in files INDEX_DATA, COMMENTS_DATA.
//If success, *index_pp will point
//to start of linked list of LOG_ENTRYs.
//Returns number of elements read.
//
//write_log() goes the other way: writes data 
//to INDEX_DATA, COMMENTS_DATA. WRITES int NUM_ELEMS AS
//FIRST 4 BYTES IN FILE INDEX_DATA.
//
//
//Brian Smith 2022-04-10

/*Copyright (C) 2022  Brian R. Smith
 * Contact: briansmith2865@gmail.com

**The source code in this file is free software: you can
**redistribute it and/or modify it under the terms of the GNU
**General Public License (GNU GPL) as published by the Free Software
**foundation, either version 3 of the License, or (at your option)
**any later version.  The code is distributed WITHOUT ANY WARRANTY;
**without even the implied warranty of MERCHANTABILITY or FITNESS
**FOR A PARTICULAR PURPOSE.  See the GNU GPL for more details.
**
**As additional permission under GNU GPL version 3 section 7, you
**may distribute non-source (e.g., minimized or compacted) forms of
**that code without the copy of the GNU GPL normally required by
**section 4, provided you include this license notice and a URL
**through which recipients can access the Corresponding Source.
**
** @licend  The above is the entire license notice
**for the source code in this file.
*/



#ifndef LOG_ENTRY_FILES_H
#define LOG_ENTRY_FILES_H


#include"log_entry_ll.h"
#include"log_entry_copy_files.h"	//Contains copy_files() which makes back up copies of prev. data. 

int read_log(LOG_INDEX** index_pp) {
	char* commentsp = NULL;
	LOG_ENTRY* pt_fArr;
	int NUM_ELEMS = 0;
	size_t COMMENTS_SIZE;
	FILE * fp = NULL;
	FILE * cfp = NULL;

	if(copy_files("INDEX_DATA_BACKUP", "INDEX_DATA") == 0 && copy_files("COMMENTS_DATA_BACKUP", "COMMENTS_DATA") == 0) {	
		fp = fopen("INDEX_DATA", "rb"); 
		cfp = fopen("COMMENTS_DATA", "rb"); fseek(cfp, 0L, SEEK_END); COMMENTS_SIZE = ftell(cfp); fseek(cfp, 0, SEEK_SET); 
		if(fp != NULL && cfp != NULL) { 
			if(fread(&NUM_ELEMS, sizeof(int),1,fp) == 1) {
				pt_fArr = (LOG_ENTRY*) malloc(NUM_ELEMS*sizeof(LOG_ENTRY));
				commentsp = (char*) malloc(COMMENTS_SIZE);
				if(fread(pt_fArr, sizeof(LOG_ENTRY), NUM_ELEMS,fp) == NUM_ELEMS) {
					if(fread(commentsp, COMMENTS_SIZE, 1,cfp) == 1){
						*(commentsp + COMMENTS_SIZE-1) = '\0';
						*index_pp = makeindex(pt_fArr, commentsp, NUM_ELEMS);
					}
				}
				else printf("\033[0;31mProblem reading from files.\033[0m\n\n");
			}
			else printf("\033[0;31mProblem getting num elements in file.\033[0m\n\n");
		}
		else printf("\033[0;31mCould not open 'dagbok.log' for reading into array.\033[0m\n\n");
		if(fp != NULL) fclose(fp); 	if(cfp != NULL) fclose(cfp);
	}
	else 
		printf("\033[0;31mCould not backup data. If you are making a new logbok this is normal.\033[0m\n\n");

	return NUM_ELEMS;
}


int write_log(LOG_INDEX* index_start, int NUM_ELEMS) {
	printf("\033[0;31mWRITING TO FILE AND EXITING.\033[0m\n");
	FILE * fp = fopen("INDEX_DATA", "wb");
	FILE * cfp = fopen("COMMENTS_DATA", "w");
	if(fp != NULL && cfp != NULL) {
		fwrite(&NUM_ELEMS, sizeof(int), 1, fp);
		LOG_INDEX* p = index_start;
		while(p != NULL) { 
			fwrite(p -> entryPtr, sizeof(LOG_ENTRY), 1, fp);
			fprintf(cfp, "%s\n", p->comments); 
			p = p -> next;
		}
		if(fp != NULL) fclose(fp); if(cfp != NULL) fclose(cfp);
		printf("\033[0;32mENTRIES WRITTEN TO FILE.\033[0m\n");
	}
	else
		printf("\033[0;31mPROBLEM WRITING TO FILE.\033[0m\n");
}




#endif