/* ====================================================== */
/*                      libraries.h                       */
/* ====================================================== */

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

/* ====================================================== */
/*    Statheres, katholikes metablhtes kai structures     */
/* ====================================================== */

#ifdef WIN32
	#define clear_screen "cls"
#else
	#define clear_screen "clear"
#endif

#define D 3            /* Megistos arithmos upo diagrafh eggrafwn prin thn anasugkrothsh */
#define N 5            /* Megisto plithos eisagwghs eggrafwn prin thn anadiorganwsh */
#define INDEX  ".ndx"  /* Epektash tou arxeioy eyrethriou */
#define MASTER ".dat"  /* Epektash tou arxeioy dedomenwn  */
#define STRINGS 30     /* Megethos twn alfarithmitikwn    */

FILE *dataf;
FILE *indexf;

char oad[STRINGS+1]="tenies.dat";  /* proepilegmeno onoma */
char oai[STRINGS+1]="tenies.ndx";

struct tenies{
	char code[10];             /* Kodikos tainias */
	char title[STRINGS+1];     /* Titlos          */
	char genre[STRINGS+1];     /* Eidos           */
	char director[STRINGS+1];  /* Skinotheths     */
	char actor1[STRINGS+1];    /* Protagonisths 1 */
	char actor2[STRINGS+1];    /* Protagonisths 2 */
	int  year;                 /* Etos            */
	int  avail;                /* diathesimothta  */
};

struct teniesIndex{
	char code[10];             /* Pedio kleidi */
	int  dief;                 /* Dieuthunsh eggrafhs sto arxeio dedomenwn */
};

struct tenies film;
struct teniesIndex *ifilm;

/* ====================================================== */
/*                  Protupa sunartisewn                   */
/* ====================================================== */

void mainmenu();          /* Emfanish tou menou epilogwn        */
void eksodos();           /* Emfanish munhmatos telous          */
void epektash();          /* Dhmiourgia/epektash arxeiou        */
int  anazhthsh();         /* Anazhthsh mesw tou index file, epistrefei th dieuthinsh ths eggrafhs sto index arxeio 'h -1 se apotuxia */
void probolh();           /* Menou tupwn probolhs               */
void probolh_index();     /* Probolh tou index arxeiou          */
void probolh_all();       /* Probolh olou tou arxeio master     */
void probolh_one();       /* Probolh mias eggrafhs              */
void prob_genre(char *);  /* Probolh ana eidos                  */
void prob_gen_av(char *); /* Probolh ana eidos k diathesimothta */
void prob_titl_taksin();  /* Probolh ana titlo, taksinomhmena   */
char* select_genre();     /* Epilogh tou eidous tenias          */
void diorthosh();         /* Diorthwsh eggrafhs                 */
void diagrafh();          /* Diagrafh eggrafhs                  */
int check_files();        /* Elegxos uparkshs arxeiwn kai epistrofh tou megethous */
void anasugkrothsh();     /* Anasugkrothsh tou index arxeiou    */
void selection_sort(struct teniesIndex *, int);

/* ====================================================== */
/*         Sunartish emfanishs tou menou epilogwn         */
/* ====================================================== */

void mainmenu(){
//	system(clear_screen);

	printf(".------------| Main menu |------------.\n");
	printf("|                                     |\n");
	printf("|  1. Dhmiourgia / Epektash           |\n");
	printf("|  2. Anazhthsh                       |\n");
	printf("|  3. Probolh                         |\n");
	printf("|  4. Diorthosh                       |\n");
	printf("|  5. Diagrafh                        |\n");
	printf("|  6. Eksodos                         |\n");
	printf("|                                     |\n");
	printf("|-------------------------------------'\n");
	printf("|  Epilogh :                          |\n");
	printf("'-------------------------------------'\n");

	return;
}

/* ====================================================== */
/*         Sunartish Emfanish munhmatos telous            */
/* ====================================================== */

void eksodos(){
//	system(clear_screen);
	printf(".------------|  Eksodos  |------------.\n");
	printf("|                                     |\n");
	printf("|   Organwsh kai diaxeirhsh arxeiwn   |\n");
	printf("|               Project               |\n");
	printf("|                                     |\n");
	printf("|                                     |\n");
	printf("|  XXXXXXXXXXXXXXXXXXXX   T-1786      |\n");
	printf("|  XXXXXXXXXXXXXXXXXXXX   T-1800      |\n");
	printf("|                                     |\n");
	printf("'-------------------------------------'\n");

//	system(clear_screen);
	exit;
}

/* ====================================================== */
/*       Sunartish taksinomhshs tou index arxeiou         */
/* ====================================================== */

void selection_sort(struct teniesIndex X[], int k){
	int i,j,t;
	struct teniesIndex temp;

	for (i=0; i<k-1; i++) {
		t = i;
		for (j=i+1; j<k; j++)
			if ( strcmp(X[t].code, X[j].code)>0 ) 
				t=j;
		temp = X[i];
		X[i] = X[t];
		X[t] = temp;
	}
}

/* ====================================================== */
/*           Sunartish Dhmiourgias/Epektashs              */
/* ====================================================== */

void epektash(){
	
	int pl, m=0, i, j, tm;
	int synexeia;

	pl = check_files();
	m = pl;
	dataf  = fopen(oad, "rb+");
	fseek(dataf, 0, SEEK_END);

	ifilm = (struct teniesIndex *) malloc((pl+N) * sizeof(struct teniesIndex));

	fputs("\n\nEISAGOGI EGGRAFON\n\n", stdout);

	do {
		printf("\nEisagogi kwdikou tenias        : ");
		scanf("%s", &film.code);
		printf("\nEisagogi titlou tenias         : ");
		scanf("%s", &film.title);
		printf("\nEisagogi eidous tenias         : \n");
		strcpy(film.genre,select_genre());
		printf("\nEisagogi skhnotheth            : ");
		scanf("%s", &film.director);
		printf("\nEisagogi prwtou protagwnisth   : ");
		scanf("%s", &film.actor1);
		printf("\nEisagogi deuterou protagwnisth : ");
		scanf("%s", &film.actor2);
		printf("\nEisagogi etous tenias          : ");
		scanf("%d", &film.year);
		printf("\nDiatheshmothta (1=NAI, 0=OXI)  : ");
		scanf("%d", &film.avail);

		/* Kataxwrisi eggrafhs sto arxeio dedomenwn */
		fwrite(&film, sizeof(struct tenies), 1, dataf);

		/* Enhmerwsh pinaka euretiriou */
		strcpy(ifilm[m].code, film.code);
		ifilm[m].dief = m;
		m++;

		printf("\n\n Thelete nea eisagogi (1=NAI, 0=OXI) : ");
		scanf("%d", &synexeia);

		if ( synexeia==1 )
			if ( m == pl+N ) {
			/* Enhmerwsh arxeiou deiktwn kai anadiorganwsh pinaka deiktwn */
				indexf = fopen(oai, "rb+"); 
				fseek(indexf, 0, SEEK_END);

				for (i=pl; i<pl+N; i++)
					fwrite(&ifilm[i], sizeof(struct teniesIndex), 1, indexf);
				fclose(indexf);

				free(ifilm);
				pl += N;    
				ifilm = malloc( (pl+N) * sizeof(struct teniesIndex));
			}
	} while ( synexeia == '1' );

	fclose(dataf);

	if ( m < pl+N) {   
	/* Enhmerwsh arxeiou deiktwn (eurethriou) */
		indexf = fopen(oai, "rb+"); 
		fseek(indexf, 0, SEEK_END);

		for (i=pl; i<m; i++) 
			fwrite(&ifilm[i], sizeof(struct teniesIndex), 1, indexf);

		fclose(indexf); 
	}

	anasugkrothsh();
}

/* ====================================================== */
/*      Sunartish anasugkrothshs tou arxeiou deiktwn      */
/* ====================================================== */

void anasugkrothsh(){
	int pl;

	pl = check_files();

	if (pl == 0) {
		printf("\n\nTo arxeio einai adeio...\n\n");
		//getchar();
		return;
	}

	indexf = fopen(oai, "rb");
	fseek(indexf, 0, SEEK_SET);
	fread(&ifilm[0], sizeof(struct teniesIndex), pl, indexf);
	fclose(indexf);

	selection_sort(ifilm, pl);

	indexf = fopen(oai, "wb");
	fwrite(&ifilm[0], sizeof(struct teniesIndex), pl, indexf);
	fclose(indexf);
 
	free(ifilm);
}

/* ======================================================== */
/* Elegxos uparkshs/dhmiourgia arxeiwn - epistrofh plhthous */
/* ======================================================== */

int check_files(){
	int pl=0;
	int choice;

	dataf  = fopen(oad, "rb");

	if (!dataf){
		do{
			printf("\nTa arxeia den uparxoun. Na dhmiourgithoun twra?");
			printf("(1=NAI, 0=OXI) : ");
			scanf("%d", &choice);
		}while(choice != 0 && choice != 1);
		if (choice == '1'){
			printf("\n\nEisagwgi onomatos arxeiou (xoris epektasi): ");
			scanf("%s", oad);

			strcpy(oai, oad);
			strcat(oad, MASTER);
			strcat(oai, INDEX);

			dataf = fopen(oad, "wb");
			indexf = fopen(oai, "wb"); 
			fclose(indexf);
		}
		else{
			printf("\nSFALMA! Ta arxeia den uparxoun, oute tha dhmiourgithoun\n");
			return 0;
		}
	}
	else{
		indexf = fopen(oai, "rb"); 
		if (!indexf) {
			fclose(dataf);
			printf("\nSFALMA! Yparxei mono to master arxeio, oxi to index.");
			eksodos();
		}
		fseek(indexf, 0, SEEK_END);
		pl = ftell(indexf) / sizeof(struct teniesIndex);
		fclose(indexf);
		fclose(dataf);
	}
	return pl;
}

/* ====================================================== */
/*                  Sunartish anazhthshs                  */
/* ====================================================== */

int anazhthsh(){
	char anaz[10];
	int choice;
	int arxi=0, telos, meso, flag=0, deiktis, pl; /* Deiktes duadikhs anazhthshs */

	pl = check_files();

	if (pl == 0) {
		printf("\n\nTo arxeio einai adeio...\n\n");
		//getchar();
		return -1;
	}

	indexf = fopen(oai, "rb");

	ifilm = malloc( pl * sizeof(struct teniesIndex));
	fread(&ifilm[0], sizeof(struct teniesIndex), pl, indexf);
	fclose(indexf);

	printf("\n\n\nEisagogi kleidiou anazitisis : ");
	scanf("%10s", anaz);

	telos = pl - 1;
	while (arxi<=telos && flag ==0) {
		meso = (arxi + telos) / 2;
		if (strcmp(anaz, ifilm[meso].code)>0 ) 
			arxi = meso + 1;
		else
		if (strcmp(anaz, ifilm[meso].code)<0 ) 
			telos = meso - 1;
		else 
			flag = 1;
	}
	if ( flag == 0 ){
		printf("\n\nH eggrafi den vrethike...\n\n");
		return -1;
	}
	else {
		do{
			printf("\nH eggrafh brethike! Na problithei twra?");
			printf("(1=NAI, 0=OXI) : ");
			scanf("%d", &choice);
		}while(choice != 0 && choice != 1);
		if (choice == 1){
			deiktis = ifilm[meso].dief;
			probolh_one(deiktis);
		}
	}
	free(ifilm);
	return meso;
}

/* ====================================================== */
/*                   Sunartish diagrafhs                  */
/* ====================================================== */

void diagrafh(){
	struct tenies temp;
	struct teniesIndex *itemp;
	int pl, i, m=0, meso; /* Πλήθος εγγραφών - δείκτης */
	int diag;
	char dg[10] = "*****", oadg[10] = "diag.dat", choice; /* Χαρακτήρες διαγραφής και όνομα αρχείου διαγραφής */
	int eld; /* Πλήθος διαγραφέντων */
	int deiktis; /* Dieuthinsh eggrafhs sto master arxeio */
	FILE *diagf; /* Αρχείο ελέγχου διαγραφής */
	FILE *tempf; /* Προσωρινό αρχείο */

	pl = check_files();

	/* perasma tou arxeiou index se pinaka */
	indexf = fopen(oai, "rb");
	ifilm = malloc( pl * sizeof(struct teniesIndex));
	fread(&ifilm[0], sizeof(struct teniesIndex), pl, indexf);
	fclose(indexf);

	meso = anazhthsh();

	if (meso == -1)               /* An h eggrafh de brethike sthn anazhthsh */
		return;
	else{
		do{
			printf("\nNa diagrafei oristika h eggrafh?");
			printf("(1=NAI, 0=OXI) : ");
			choice = getchar();
		}while(choice != '0' && choice != '1');
		if (choice == 1){
			printf("\n\nH eggrafi diagrafetai...\nPerimenete...\n\n");
			deiktis = ifilm[meso].dief;
			fseek(dataf, deiktis * sizeof(struct tenies), SEEK_SET);
			temp = film;
			strcpy(temp.code, dg); 
			fwrite(&temp, sizeof(struct tenies), 1, dataf);

			/* Ενημέρωση πίνακα ευρετηρίου */
			for (i=meso; i<pl-1; i++)
				ifilm[i] = ifilm[i+1];

			/* Plithos eggrafwn meiwthike kata 1 */
			pl--;

			/* Enhmerwsh arxeiou euretiriou */
			indexf = fopen(oai, "wb"); 
			fwrite(&ifilm[0], sizeof(struct teniesIndex), pl, indexf);
			fclose(indexf);

			/* Ενημέρωση αρχείου ελέγχου διαγραφών */
			diagf = fopen(oadg, "rb+");
			if ( !diagf ) {
				diagf = fopen(oadg, "wb");
				eld = 1;
				fwrite(&eld, sizeof(int), 1, diagf);
				fclose(diagf);
			}
			else {
				fread(&eld, sizeof(int), 1, diagf);
				eld++;
				if ( eld <= D ) {
					fseek(diagf, 0, SEEK_SET);
					fwrite(&eld, sizeof(int), 1, diagf);
					fclose(diagf);
				}
				else{
					/* Antigrafh tou master arxeiou sto temp, ektos apo tis eggrafes pou diagrafikan */

					dataf = fopen(oad, "rb");
					fseek(dataf, 0, SEEK_SET);
					tempf = fopen("temp.dat", "wb");

					while (! feof(dataf) ) {
						fread(&film, sizeof(struct tenies), 1, dataf);   
						if (! feof(dataf) && strcmp(film.code, dg)!=0) {
							fwrite(&film, sizeof(struct tenies), 1, tempf);
						}
					}
	
					fclose(dataf);
					fclose(tempf);
					/* telos antigrafhs */

					dataf = fopen(oad, "wb");
					tempf = fopen("temp.dat", "rb");
					indexf = fopen(oai, "wb");
	
					fseek(tempf, 0, SEEK_END);
					m = ftell(tempf) / sizeof(struct tenies);
					itemp = malloc(m * sizeof(struct teniesIndex));
					fseek(tempf, 0, SEEK_SET);
					m = 0;
	
					while (! feof(tempf) ) {
						fread(&film, sizeof(struct tenies), 1,tempf);   
						if (! feof(tempf) ) {
							fwrite(&film, sizeof(struct tenies), 1, dataf);   
							strcpy(itemp[m].code, film.code);
							itemp[m].dief = m; 
							m++;
						}
					}
	
					/* Επαναταξινόμηση και επανοφαρά του αρχείου ευρετήριου */
	
					selection_sort(itemp, m);
	
					fwrite(&itemp[0], sizeof(struct teniesIndex), m, indexf);
					fclose(indexf);
	 
					free(itemp);
	
					fclose(tempf);
	
					/* Ενημέρωση αρχείου διαγραφής */           
					diagf = fopen(oadg, "wb");
					eld = 0;
					fwrite(&eld, sizeof(int), 1, diagf);
					fclose(diagf);
				}
			}
		}
	}
	fclose(dataf);
}