#include "proc.h"

#include <unistd.h>
#include <fcntl.h>

#define SQR(n) (n) * (n)
#define FILDES_MATRIX_SIZE(n) SQR(n)
#define READ_FILDES_I   read_fildes[from * n + to]
#define WRITE_FILDES_I write_fildes[to * n + from]

static int pipes_matrix_init(FILE *log, size_t n, int *read_fildes,
                int *write_fildes) {
        int fildes[2];
        for (size_t from = 0; from < n; ++from) {
                for (size_t to = 0; to < n; ++to) {
                        if (from == to)
                                continue;

                        if (pipe(fildes)) {
                                perror("opening pipes");
                                return 1;
                        }
                        fprintf(log, "PIPES %d and %d are paired\n",
                                        fildes[0], fildes[1]);
                        fcntl(fildes[0], F_SETFL, O_NONBLOCK);
                        fcntl(fildes[1], F_SETFL, O_NONBLOCK);
                         READ_FILDES_I = fildes[0];
                        WRITE_FILDES_I = fildes[1];
                }
        }
        return 0;
}

static int pipes_matrix_extract_fildes(FILE *log, size_t n, int *read_fildes,
                int *write_fildes, size_t i, int *read_fildes_row,
                int *write_fildes_row) {
        for (size_t from = 0; from < n; ++from) {
                for (size_t to = 0; to < n; ++to) {
                        if (from == to) {
                                continue;
                        }

                        if (to == i) {
                                 read_fildes_row[from] = READ_FILDES_I;
                        } else {
                                if (close(READ_FILDES_I)) {
                                        perror("closing read fildes");
                                        return 1;
                                } else {
                        fprintf(log, "CLOSING: %zu:"
                                        "read  form %zu to %zu: %d\n",
                                        i, from, to, READ_FILDES_I);
                                }
                        }

                        if (from == i) {
                                write_fildes_row[to] = WRITE_FILDES_I;
                        } else {
                                if (close(WRITE_FILDES_I)) {
                                        perror("closing write fildes");
                                        return 1;
                                } else {
                        fprintf(log, "CLOSING: %zu:"
                                        "write from %zu to %zu: %d\n",
                                        i, from, to, WRITE_FILDES_I);
                                }
                        }
                }
        }
        write_fildes_row[i] = 1337;
         read_fildes_row[i] = 1488;
        return 0;
}

int await_all(Process *me, int16_t type) {
        for (uint8_t i = 1; i < me->fildes_num; ++i) {
                if (i == me->id)
                        continue;
                Message msg;
                if (receive(me, i, &msg)) {
                        fprintf(stderr, "Failed to receive: p = %d, i = %d\n",
                                        me->id, i);
                        return 1;
                }
                if (msg.s_header.s_type != type) {
                        fprintf(stderr, "HHH:((( \n");
                }

        }
        return 0;
}

int proc_init(uint8_t n, Process *proc, FILE *log) {
        int  read_fildes[FILDES_MATRIX_SIZE(n)];
        int write_fildes[FILDES_MATRIX_SIZE(n)];
        pipes_matrix_init(log, n, read_fildes, write_fildes);

        proc->id = PARENT_ID;
        proc->fildes_num = n;
        for (uint8_t i = 1; i < n; ++i) {
                pid_t pid = fork();
                if (pid == 0) {
                        proc->id = i;
                        break;
                }
        }
        pipes_matrix_extract_fildes(log, n, read_fildes, write_fildes,
                        proc->id, proc->read_fildes, proc->write_fildes);
        return 0;
}

void proc_destruct(Process *proc) {

        for (uint8_t i = 0; i < proc->fildes_num; ++i) {
                if (i != proc->id) {
                        close(proc->read_fildes[i]);
                        close(proc->write_fildes[i]);
                }
        }
}