#include "display.c"

int get_date_index(creneau* edt, int len_creneau, date d) {
    // could be done in log(n), I know
    int x = -1;
    for(int i = 0; i < len_creneau; i++) {
        x = date_dist(edt[i].date, d);
        if(x >= 0) {
            return i;
        }
    } 
    return -1;
}

int get_next_friday(creneau* edt, int len_creneau, date d) {
    // could be done in log(n), I know again
    int x = -1;
    for(int i = 0; i < len_creneau; i++) {
        x = date_dist(d, edt[i].date);
        //printf("%d\n", x);
        if(x >= 0 && (i == len_creneau-1 || date_dist(d, edt[i+1].date) - x > 1)) {
            return i;
        }
    } 
    return -1;
}

int get_fst_offset(creneau* edt, date d) {
    return (date_dist(edt[0].date, d));
}

bool is_allowed_MP2I(creneau* edt, int len_edt, int grp, date end) {
    /* conditions (AND) :
    1) Alternate between physics and english
    2) Pattern for math colles is exactly 3-1-3-1-...
    3) Between 1 and 2 colles per week and per group (exclusing special colles such as Info)
    4) Special colles (aka INFO) at least 1 every 6 weeks
    */

    int end_id = get_next_friday(edt, len_edt, end); // index of first date that is later than end
    if(end_id == -1) {
        return true;
    }

    printf("EndId : %d\n", end_id);

    // 1) PC/AGL alternance
    int agl = 0;
    int pc = 0;
    char has_to_be = 'n'; // 'n' = not set, 'a' = AGL and 'p' = PC
    for(int i = end_id-1; i >= 0; i--) {
        if(i == 0 || (date_dist(edt[0].date, edt[i].date)%7 == 4 && date_dist(edt[0].date, edt[i+1].date)%7 != 4)) { 
            //printf("Checking AGL/PC...\n");
            // currently pointed date is the last friday of the week
            // since we are going down, friday <==> reset variables and check for conflicts
            if(agl + pc != 1) {
                printf("Missing english or physics colle at index %d for group %d (found %d)\n", i, grp, agl+pc);
                return false;
            } else if(has_to_be == 'p' && pc != 1) {
                printf("Wrong number of physics colle at index %d for group %d\n", i, grp);
                return false;
            } else if(has_to_be == 'a' && agl != 1) {
                printf("Wrong number of english colle at index %d for group %d\n", i, grp);
                return false;
            }
            if(has_to_be == 'n') {
                if(agl == 1) {
                    has_to_be = 'p';
                } else {
                    has_to_be = 'a';
                }
            }
            agl = 0;
            pc = 0;
        }
        if(edt[i].group == grp && edt[i].mat == ENGLISH) {
            agl += 1;
        } if(edt[i].group == grp && edt[i].mat == PHYSICS) {
            pc += 1;
        }
    }

    // 2) Math colles
    int math = 0;
    int last_no_math = -1;
    for(int i = end_id-1; i >= 0; i--) {
        if(i == 0 || (date_dist(edt[0].date, edt[i].date)%7 == 4 && date_dist(edt[0].date, edt[i+1].date)%7 != 4)) { 
            if(math != 0 && math != 1) {
                printf("Invalid number of math colles at index %d for group %d\n", i, grp);
                return false;
            } else if(math == 0) {
                if(last_no_math != -1 && last_no_math != 3) {
                    printf("Invalid rotation of math colles at index %d for group %d\n", i, grp);
                    return false;
                }
                last_no_math = 0;
            } else if(last_no_math > 3) {
                printf("Too many math colles at index %d for group %d\n", i, grp);
                return false;
            } else {
                if(last_no_math != -1) {
                    last_no_math += 1;
                }
            }
            math = 0;
        }
        if(edt[i].group == grp && edt[i].mat == MATH) {
            math += 1;
        }
    }

    // 3) Count
    int n_colles = 0;
    for(int i = end_id-1; i >= 0; i--) {
        if(i == 0 || (date_dist(edt[0].date, edt[i].date)%7 == 4 && date_dist(edt[0].date, edt[i+1].date)%7 != 4)) { 
            if(n_colles != 1 && n_colles != 2) {
                printf("Invalid number of colles at index %d for group %d (found %d)", i, grp, n_colles);
                return false;
            }
            n_colles= 0;
        }
        if(edt[i].group == grp) {
            n_colles++;
        }
    }

    // 4) Info
    int inf = 0;
    int last_no_inf = -1;
    for(int i = end_id-1; i >= 0; i--) {
        if(i == 0 || (date_dist(edt[0].date, edt[i].date)%7 == 4 && date_dist(edt[0].date, edt[i+1].date)%7 != 4)) { 
            if(inf != 0 && inf != 1) {
                printf("Invalid number of info colles at index %d for group %d\n", i, grp);
                return false;
            } else if(inf == 0) {
                if(last_no_inf != -1 && last_no_inf != 5) {
                    printf("Invalid rotation of info colles at index %d for group %d\n", i, grp);
                    return false;
                }
                last_no_inf = 0;
            } else if(last_no_inf > 5) {
                printf("Too many info colles at index %d for group %d\n", i, grp);
                return false;
            } else {
                if(last_no_inf != -1) {
                    last_no_inf += 1;
                }
            }
            inf = 0;
        }
        if(edt[i].group == grp && edt[i].mat == INFO) {
            inf += 1;
        }
    }
    return true;
}

/*
    for(int i = end_id-1; i >= 0; i--) {
        if(i == 0 || (date_dist(edt[0].date, edt[i].date)%7 == 4 && date_dist(edt[0].date, edt[i+1].date)%7 != 4)) { 
            // Check week
        }
        // Detect colles
    }
*/

/*
void generate_colles_v1(creneau* edt, int len_edt, int n_groups, colleur* chads, int n_chads) {

}
*/