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


struct player {
    int playerNumber;
    int beaten[64];
    int stage;
    struct player *next;
    struct player *prev;
};

int powerof2(int i) {
    int j = 0;
    while (i != 1) {
        if (i % 2 != 0) {
            printf("Invalid");
            exit(0);
        }
        i /= 2;
        j++;
        
    }
    return j;
}

void stage(int roundd, struct player *head) {
    struct player *player1 = NULL;
    struct player *player2 = NULL;
    struct player *cur = head;

    printf("Stage %d:\n", roundd);
    while (cur != NULL) {
        if (cur->stage >= roundd) {
            if (player1 == NULL) {
                player1 = cur;
            }
            else if (player2 == NULL) {
                player2 = cur;
                printf("%dv%d ", player1->playerNumber, player2->playerNumber);
                player1 = NULL;
                player2 = NULL;
            }
        }
        cur = cur->next;
    }
    printf("\n");
}

void results(struct player *head, int N) {
    for (int j = 0; j < N; j++) {
        struct player *player1 = NULL;
        struct player *player2 = NULL;
        struct player *cur = head;
    
        printf("***************\n");
        while (cur != NULL) {
            if (cur->stage >= j) {
                if (player1 == NULL) {
                    player1 = cur;
                }
                else if (player2 == NULL) {
                    player2 = cur;
                    printf("%dv%d ", player1->playerNumber, player2->playerNumber);
                    player1 = NULL;
                    player2 = NULL;
                }
            }
            cur = cur->next;
        }
        printf("\n");
    }
}

struct player *get_suitable_player(struct player *head, int j) {
    struct player *ret = NULL;
    while(head != NULL) {
        if(head->stage >=j) {
            ret = head;
            return ret;
        }
        head = head->next; 
    }
    return ret;
}


int main() {
    printf("Welcome to the Football Tournament.\n\nHow namy players are playing: (Must be a factor of 2) \n");
    int temp;
    scanf("%d", &temp);
    int N = powerof2(temp);
    printf("Players playing: 2^%d\n\n" ,N);
    
    struct player *head = NULL;
    struct player *cur = NULL;
            
    for (int i = 0; i<temp; i++) {
        struct player *player = malloc(sizeof(struct player));
        player -> playerNumber = i + 1;
        
        if (head == NULL) {
        head = player;
        cur = player;
        }
        else {
        cur->next = player;
        player->prev = cur;
        cur = player;
        }
    }


    cur = head;
        for (int i = 0; i < temp; i++) {
            while (cur != NULL) {
                printf("***************\n%dv%d\n", cur->playerNumber , cur->next->playerNumber);
                int winner;
                scanf("%d", &winner);
                if (winner == cur->playerNumber) {
                    cur->stage++;
                    cur->beaten[i] = cur->next->playerNumber;
                }
                else {
                    cur->next->stage++;
                    cur->next->beaten[i] = cur->playerNumber;
                }
            cur = cur->next->next;
            }
        }
    
    struct player *new = NULL;
    for (int j = 1; j <= N; j++) {
        
        struct player *first = get_suitable_player(new, j);
        struct player *second = get_suitable_player(first->next, j);
        
        printf("***************\n%dv%d\n", first->playerNumber, second->playerNumber);
        int winner;
        scanf("%d", &winner);
        if (winner == first->playerNumber) {
            first->stage++;
        // add beaten for both cases.
        }
        else {
            second->stage++;
        
        }
        new = second->next;
    }



    int choice;
    do {
        printf("Welcome to the Football Tournament.\nPick an option:\n\n");
        printf("1)Play\n2)View Stages\n3)View Player\n4)Quit\n\n");
        scanf("%d", &choice);
        
        switch (choice) {
            
            case 1:
                results(head, N);
                
            break;
                
            case 2:
                int lol;
                printf("Stage Number: ");
                scanf("%d", &lol);
                cur = head;
                stage(lol, head);
                printf("\n");
                
            break;
            
            case 3:
            // make into a function when stages function works.
                int player;
                printf("Player Number: ");
                scanf("%d", &player);
                struct player *cur = head;
                
                //add cur != NULL maybe
                
                while (cur->playerNumber != player) {
                    cur = cur->next;
                }
                printf("Players beaten by player %d are: ", player);
                for (int i = 0; i <cur->stage; i++) {
                    printf("%d ", cur->beaten[i]);
                }
                
            break;
            
            case 4:
                printf("End.");
                
            break;
            
            default:
                printf("Invalid");
            
        }
    } while (choice != 4);
    
    return 0;

}