/* 
----------------------------------------
|  Adresse   |  Registre  |  Modifié   | 
----------------------------------------
|            |            |            |            
|            |            |            |            
|            |            |            |            
|      i     | 0x777756b8 |     int    |       
|    size    | 0x777756b8 |     int    |        
----------------------------------------
*/

#include "tables.h"
#define NB_REG 4
#define MEM_SIZE 1024
#define NB_INSTRUCTIONS 1024



struct case_adresse {
	int adresse;
	int registre;
	char modifie;
};

struct case_adresse tableau[MEM_SIZE];
int registres[NB_REG];
int traduction_JMP[NB_INSTRUCTIONS];

void init (void) {
  int i;
	struct case_adresse case_courante = {0, -1, 0};
	for (i=0; i<MEM_SIZE; i++) {
		case_courante.adresse = i;
		tableau[i] = case_courante;
	}
	for (i=0; i<NB_REG; i++) {
		registres[i] = 0;
	}	
}

void print_case_adresse(struct case_adresse case_courante) {
	printf("{addr : %d ; reg : %d ; modi : %d}\n", case_courante.adresse, case_courante.registre, (int)case_courante.modifie);
}

void print() {
  int i;
	for (i=0; i<MEM_SIZE; i++) {
		print_case_adresse(tableau[i]);
	}
}


struct case_adresse get_info(int adresse) {
	return tableau[adresse];
}

int get_adresse (int registre) {
	int i = 0;
	while (i < MEM_SIZE && tableau[i].registre != registre) {
		i++;
	}
	if (i == MEM_SIZE) {
		return -1;
	} else {
		return tableau[i].adresse;
	}
}

void set_registre(int adresse, int registre) {
	tableau[adresse].registre = registre;
}

void set_modifie(int adresse, char modifie) {
	tableau[adresse].modifie = modifie;
}

void increment_time() {
	int i;
	for (i=0; i<NB_REG; i++) {
		registres[i]++;
	}
}

void refresh_registre(int registre) {
	registres[registre] = 0;
}

int get_register() {
	int i;
	int index_max = 0;
	for (i=0; i<NB_REG; i++) {
		if (registres[index_max] < registres[i]) {
			index_max = i;
		}
	}
	return index_max;
}

int get_reg_write(int adresse, FILE * file, int * added_instruction) {
	if (adresse == -1) {
		int dispo = get_register();
		int previous_addr = get_adresse(dispo);
		if (previous_addr != -1) {
			struct case_adresse ancienne_case = get_info(previous_addr);
			if (ancienne_case.modifie == 1) {
				fprintf(file, "STORE %d %d\n", previous_addr, dispo);
				*added_instruction = (*added_instruction) + 1;
				set_modifie(previous_addr, 0);
			}
			set_registre(previous_addr, -1);
		}
		return dispo;
	} else {
		set_modifie(adresse, 1);
		struct case_adresse ma_case = get_info(adresse);
		if (ma_case.registre == -1) {
			int dispo = get_register();
			int previous_addr = get_adresse(dispo);
			if (previous_addr != -1) {
				struct case_adresse ancienne_case = get_info(previous_addr);
				if (ancienne_case.modifie == 1) {
					*added_instruction = (*added_instruction) + 1;
					fprintf(file, "STORE %d %d\n", previous_addr, dispo);
					set_modifie(previous_addr, 0);
				}
				set_registre(previous_addr, -1);
			}
			set_registre(adresse, dispo);
			refresh_registre(dispo);
			return dispo;
		} else {
			refresh_registre(ma_case.registre);
			return ma_case.registre;
		}
	}
}

int get_reg_read(int adresse, FILE * file, int * added_instruction) {
	struct case_adresse ma_case = get_info(adresse);
	if (ma_case.registre == -1) {
		int dispo = get_register();
		int previous_addr = get_adresse(dispo);
		if (previous_addr != -1) {
			struct case_adresse ancienne_case = get_info(previous_addr);
			if (ancienne_case.modifie == 1) {
				*added_instruction = (*added_instruction) + 1;
				fprintf(file, "STORE %d %d\n", previous_addr, dispo);
				set_modifie(previous_addr, 0);
			}
			set_registre(previous_addr, -1);
		}
		*added_instruction = (*added_instruction) + 1;
		fprintf(file, "LOAD %d %d\n", dispo, adresse);
		set_registre(adresse, dispo);
		refresh_registre(dispo);
		return dispo;
	} else {
		refresh_registre(ma_case.registre);
		return ma_case.registre;
	}
}


int flush_and_init(FILE * file) {
	int i;
	int added_instruction = 0;
	for (i = 0; i<MEM_SIZE; i++) {
		if (tableau[i].registre != -1) {
			if (tableau[i].modifie == 0) {
				tableau[i].registre = -1;
			} else {
				fprintf(file, "STORE %d %d\n", i, tableau[i].registre);
				added_instruction++;
				tableau[i].registre = -1;
				tableau[i].modifie = 0;
			}
		}
	}
	for (i=0; i<NB_REG; i++) {
		registres[i] = 0;
	}
	return added_instruction;
}

void new_instruction(int nb_inst) {
	static int last_intruction_adresse = 0;
	static int current_instruction = 0; 
	traduction_JMP[current_instruction] = last_intruction_adresse;
	current_instruction++;
	last_intruction_adresse += nb_inst;
}