// golfScores.c : Questo file contiene la funzione 'main', in cui inizia e termina l'esecuzione del programma.
//

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

/* Maximum length of names */
#define STRMAX 20
/* Maximum length of rows */
#define MAX_ROW 80

struct dnode
{
    int score;
    char player[STRMAX+1];
    struct dnode* prev;
    struct dnode* next;
};

struct dnode* first;  /* pointer to the first list item */
struct dnode* last;   /* pointer to the last list item  */

struct dnode* createNode(char* playerName, int playerScore)
{
    struct dnode* newNode = (struct dnode*)malloc(sizeof(struct dnode));
    if (newNode != NULL)
    {
        strcpy(newNode->player, playerName);
        newNode->score = playerScore;
        newNode->next = NULL;
        newNode->prev = NULL;
    }
    return(newNode);

}

void printList(struct dnode* head) {
    struct dnode* current = head;
    while (current != NULL) {
        printf("%s ", current->player);
        printf("%d\n", current->score);
        current = current->next;
    }
    printf("\n");
}

void printListDescending(struct dnode* head) {
    struct dnode* current = head;
    while (current != NULL) {
        if (current->next == NULL)
            break;
        else
            current = current->next;
    }
    if (current != NULL)
    {
        while (current != head)
        {
            printf("%s ", current->player);
            printf("%d\n", current->score);
            current = current->prev;
        }
        printf("%s ", current->player);
        printf("%d\n", current->score);
    }
    printf("\n");
}

void saveData(FILE *fo, struct dnode* head) {
    struct dnode* current = head;
    while (current != NULL) {
        if (fprintf(fo, "%s;%d\n", current->player, current->score) < 0)
        {
            perror("Error saving data to file");
            break;
        }
        current = current->next;
    }
    printf("\n");
}

void printPlayersSameScore(struct dnode* pnode) {

    int playerScore = 0;
    struct dnode* current = pnode;
    if (pnode != NULL)
    {
        playerScore = pnode->score;
    }
    while (current != NULL && current->score == playerScore) {
        printf("%s ", current->player);
        printf("%d\n", current->score);
        current = current->next;
    }
    current = pnode->prev;
    while (current != NULL && current->score == playerScore) {
        printf("%s ", current->player);
        printf("%d\n", current->score);
        current = current->prev;
    }
    printf("\n");
}

struct dnode* searchItem(struct dnode* head, char* playerToSearch)
{
    while ((head != NULL) && (strcmp(head->player,playerToSearch)!=0))
        head = head->next;
    return(head);
}

void head_insert(struct dnode** ptr, struct dnode* newNode)
{
    struct dnode* tmp = NULL;

    tmp = *ptr;
    *ptr = newNode;
    if (tmp != NULL)
    {
        tmp->prev = newNode;
        (*ptr)->next = tmp;
    }
    else
    {
        (*ptr)->next = NULL;
        (*ptr)->prev = NULL;
    }
}

void tail_insert(struct dnode** ptr, struct dnode* newNode)
{
    struct dnode* tmp = NULL;

    if (*ptr == NULL)
    {
        *ptr = newNode;
        (*ptr)->next = NULL;
        (*ptr)->prev = NULL;
    }
    else
    {
        tmp = *ptr;
        while (tmp->next != NULL)
            tmp = tmp->next;
        tmp->next = newNode;
        newNode->prev = tmp;
        newNode->next = NULL;
    }
}

void insert_x_score(struct dnode** ptr, struct dnode* newNode)
{
    struct dnode* tmp = NULL;

    if (*ptr == NULL)
    {
        *ptr = newNode;
        (*ptr)->next = NULL;
        (*ptr)->prev = NULL;
    }
    else
    {
        if ((*ptr)->score >= newNode->score)
        {
            newNode->next = *ptr;
            newNode->prev = NULL;
            (*ptr)->prev = newNode;
            *ptr = newNode;
        }
        else
        {
            tmp = *ptr;
            while (tmp->next != NULL)
            {
                if ((tmp->score <= newNode->score) && (tmp->next->score >= newNode->score))
                {
                    newNode->next = tmp->next;
                    tmp->next->prev = newNode;
                    tmp->next = newNode;
                    newNode->prev = tmp;
                    break;
                }
                else
                {
                    tmp = tmp->next;
                }
            }
            if (tmp->next == NULL)
            {
                tmp->next = newNode;
                newNode->next = NULL;
                newNode->prev = tmp;
            }
        }
    }
}

int updateData(FILE* fi, struct dnode* head)
{
    char row[MAX_ROW + 1];
    while (!feof(fi))
    {
        if (fgets(row, MAX_ROW, fi) != row)
        {
            if (feof(fi))
            {
                break;
            }
            else
            {
                perror("Error reading file input");
                return(3);
            }
        }
        char player[STRMAX + 1];
        int score;
        char* t;
        if ((t = strtok(row, ";")) != NULL)
        {
            strcpy(player, t);
            if ((t = strtok(NULL, ";")) != NULL)
            {
                score = atoi(t);
            }
        }
        else
        {
            printf("Error reading tokens from golf scores file");
            return(4);
        }
        //printf("Player %s - score %d\n", player, score);
        struct dnode* playerNode = searchItem(head, player);
        if (playerNode != NULL)
        {
            playerNode->score += score;
        }
        else
        {
            printf("Error searching player %s: not found", player);
        }
    }
    return(0);
}

struct dnode* insertionSort(struct dnode* head)
{
    struct dnode* headList = NULL;
    struct dnode* current = head;
    while (current != NULL)
    {
        struct dnode* newNode = createNode(current->player, current->score);
        if (newNode != NULL)
        {
            insert_x_score(&headList, newNode);
        }
        else
        {
            printf("Error creating newNode");
            return(NULL);
        }
        current = current->next;
    }
    while (head != NULL)
    {
        current = head->next;
        free(head);
        head = current;
    }
    return(headList);
}

int main(int argc, char *argv[])
{
    char row[MAX_ROW+1];
    struct dnode* headList = NULL;
    struct dnode* headListTail = NULL;
    struct dnode* headListScore = NULL;

    if (argc != 2)
    {
        printf("Error: usage %s golf_scores_filename\n", argv[0]);
        return(1);
    }
    FILE* fi = fopen(argv[1], "r");
    if (fi == NULL)
    {
        perror("Error opening input file\n");
        return(2);
    }

    while (!feof(fi))
    {
        if (fgets(row, MAX_ROW, fi) != row)
        {
            if (feof(fi))
            {
                break;
            }
            else
            {
                perror("Error reading file input");
                return(3);
            }
        }
        char player[STRMAX+1];
        int score;
        char* t;
        if ((t = strtok(row, ";")) != NULL)
        {
            strcpy(player, t);
            if ((t = strtok(NULL, ";")) != NULL)
            {
                score = atoi(t);
            }
        }
        else
        {
            printf("Error reading tokens from golf scores file");
            return(4);
        }
        //printf("Player %s - score %d\n", player, score);
        struct dnode* newNode = createNode(player, score);
        if (newNode != NULL)
        {
            //head_insert(&headList, newNode);
            //tail_insert(&headListTail, newNode);
            insert_x_score(&headListScore, newNode);
        }
        else
        {
            printf("Error creating newNode");
            return(5);
        }
    }
    fclose(fi);
    //printList(headListScore);

    bool menu = true;
    while (menu)
    {
        printf("[1] Print list in ascending order of scores\n");
        printf("[2] Print list in decending order of scores\n");
        printf("[3] Search player\n");
        printf("[4] Load new scores\n");
        printf("[5] Save scores\n");
        printf("[6] Exit\n");
        printf("\nMake your choice:");
        char choice[STRMAX + 1];
        if (gets_s(choice, STRMAX) == NULL)
        {
            printf("Error reading choice\n");
            return(6);
        }
        /*else
        {
            printf("Choice %s\n", choice);
        }*/
        int myChoice = atoi(choice);
        switch (myChoice)
        {
            case 1:
                printf("Printing current list\n");
                printList(headListScore);
                break;
            case 2:
                printf("Printing current list\n");
                printListDescending(headListScore);
                break;
            case 3:
            {
                char playerName[STRMAX + 1];
                printf("\nInsert player name:");
                if (gets_s(playerName, STRMAX) == NULL)
                {
                    printf("Error reading player name\n");
                    return(7);
                }
                else
                {
                    printf("Player to be searched %s\n", playerName);
                }
                struct dnode* playerFound = searchItem(headListScore, playerName);
                if (playerFound != NULL)
                {
                    printPlayersSameScore(playerFound);
                }
                else
                {
                    printf("Player %s not found\n", playerName);
                }
                break;
            }
            case 4:
            {
                printf("Loading new scores..\n");
                char filenameToRead[MAX_ROW + 1];
                printf("\nInsert filename with new scores:");
                if (gets_s(filenameToRead, MAX_ROW) == NULL)
                {
                    printf("Error reading file name\n");
                    return(9);
                }
                FILE* fi = fopen(filenameToRead, "r");
                if (fi != NULL)
                {
                    int retc = updateData(fi, headListScore);
                    if (retc != 0)
                    {
                        printf("Error updating scores data\n");
                    }
                    fclose(fi);
                }
                else
                {
                    perror("Error opening file");
                    printf("Error opening file '%s.\n", filenameToRead);
                }
                headListScore = insertionSort(headListScore);
                if (headListScore == NULL)
                {
                    printf("Error sorting list.\n");
                    return(10);
                }
                break;
            }
            case 5:
            {
                char filenameToSave[MAX_ROW + 1];
                printf("\nInsert filename where saving data:");
                if (gets_s(filenameToSave, MAX_ROW) == NULL)
                {
                    printf("Error reading file name\n");
                    return(7);
                }
                FILE* fo = fopen(filenameToSave, "r");
                if (fo != NULL)
                {
                    // Close the file after checking existence
                    fclose(fo);
                    printf("File '%s' exists.\n", filenameToSave);
                    printf("Do you want to overwrite it (Y/N):");
                    if (gets_s(choice, STRMAX) == NULL)
                    {
                        printf("Error reading choice\n");
                        return(11);
                    }
                    char c = choice[0];
                    if ((c == 'n') || (c == 'N'))
                        printf("\nPlease choose a different filename\n");
                    else if ((c == 'y') || (c == 'Y'))
                    {
                        printf("\nSaving data in file '%s'.\n", filenameToSave);
                        fo = fopen(filenameToSave, "w");
                        if (fo == NULL)
                        {
                            perror("Error opening file for saving data");
                            return(8);
                        }
                        saveData(fo, headListScore);
                        fclose(fo);
                    }
                    else
                        printf("\nBad choice. Please choose a different filename\n");
                }
                else
                {
                    printf("Saving data in file '%s'.\n", filenameToSave);
                    fo = fopen(filenameToSave, "w");
                    if (fo == NULL)
                    {
                        perror("Error opening file for saving data");
                        return(8);
                    }
                    saveData(fo, headListScore);
                    fclose(fo);
                }
                break;
            }
            case 6:
                menu = false;
                break;
            default:
                printf("Choice %s is a bad choice\n", choice);
                break;
        }
    }
    return(0);
}