/*Khai Quang Ho, kho19@student.aau.dk, A402, SW */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define FILENAME "kampe-2018-2019.txt"
#define MAX_TEAMS 14
#define MAX_GAMES 182
#define MAX_STR 5
#define MAX_LINE 60

typedef struct game{
    char weekday[MAX_STR];
    char date[MAX_STR];
    char time[MAX_STR];
    char teamA_name[MAX_STR];
    char teamB_name[MAX_STR];
    int teamA_goals;
    int teamB_goals;
    int crowd_size;
}game;

typedef struct team{
    char name[MAX_STR];
    int points;
    int goalsFor;
    int goalsAgainst;
}team;

int read_games(const char *filename, game game_list[]);
int h(const char name[], team team_list[]);
void get_team_stats(team *team_list, const game *game_list);
int sort (const void *a, const void *b);
void print_teams(team team_list[]);

int main(void) {

    game game_list[MAX_GAMES] = {{{0}}};
    team team_list[MAX_TEAMS] = {{{0}}};

    if(read_games(FILENAME, game_list) == -1){
        printf("Can't open file \"%s\"\n", FILENAME);
        return -1;
    }

    get_team_stats(team_list, game_list);
    qsort(team_list, MAX_TEAMS, sizeof(team), sort);
    print_teams(team_list);

    return 0;
}

/* reads file and stores data in game_list */
int read_games(const char filename[], game game_list[]){

    int i = 0;
    char str[MAX_LINE];

    FILE *fp;
    fp = fopen(filename, "r");

    if(fp != NULL){

        for(i = 0; fgets(str, MAX_LINE, fp) != NULL; i++){

            sscanf(str, "%s %s %s %s - %s %d - %d %d",
                game_list[i].weekday,
                game_list[i].date,
                game_list[i].time,
                game_list[i].teamA_name,
                game_list[i].teamB_name,
                &game_list[i].teamA_goals,
                &game_list[i].teamB_goals,
                &game_list[i].crowd_size);
        }
    }

    else
        return -1; /* file could not be opened */

    fclose(fp);

    return 0;
}

/* takes data from game_list and store relevant data to team_list*/
void get_team_stats(team *team_list, const game *game_list){

    int i;

    for(i = 0; i < MAX_GAMES; i++){

        /* shorthands*/
        game current = game_list[i];
        int teamA = h(game_list[i].teamA_name, team_list);
        int teamB = h(game_list[i].teamB_name, team_list);

        /* copies name into team struct from game struct */
        strcpy(team_list[teamA].name, current.teamA_name);
        strcpy(team_list[teamB].name, current.teamB_name);

        /* increment goals for and against and assign name*/
        team_list[teamA].goalsFor += current.teamA_goals;
        team_list[teamA].goalsAgainst += current.teamB_goals;
        team_list[teamB].goalsFor += current.teamB_goals;
        team_list[teamB].goalsAgainst += current.teamA_goals;

        /* calc points */
        if(current.teamA_goals > current.teamB_goals){
            team_list[teamA].points += 3;
        }
        else if(current.teamB_goals > current.teamA_goals){
            team_list[teamB].points += 3;
        }
        else if(current.teamA_goals == current.teamB_goals){
            team_list[teamA].points += 1;
            team_list[teamB].points += 1;
        }
    }
}

/* convert team name to index */
int h( const char name[], team team_list[]){

    int key = (unsigned int)name % MAX_TEAMS; /* modulo can return negative values in c */
    int i = key;

    while(strcmp(team_list[i].name, "") != 0 && strcmp(team_list[i].name, name) != 0)
        i = (i + 1) % MAX_TEAMS;

    /* if team name doesnt exist in list, insert it*/
    if(strcmp(team_list[i].name, "") == 0)
        strcpy(team_list[i].name, name);

    return i;
}

/* sorts teams after superliga rules */
int sort (const void *a, const void *b){

    const team teamA = *(team *)a;
    const team teamB = *(team *)b;

    int valueA = teamA.points;
    int valueB = teamB.points;

    if(valueA == valueB){
        valueA = teamA.goalsFor - teamA.goalsAgainst;
        valueB = teamB.goalsFor - teamB.goalsAgainst;

        if(valueA == valueB){
            valueA = teamA.goalsFor;
            valueB = teamB.goalsFor;

            if(valueA == valueB){
                valueA = teamB.goalsAgainst;
                valueB = teamA.goalsAgainst;
            }
        }
    }

    return ( ( valueB > valueA ) - ( valueA > valueB )  );
}

/* prints out the team standing */
void print_teams(team team_list[]){

    int i;

    printf("  %4s | %-4s | %-4s | %-4s | %-4s | %-4s |\n\n", "Pos", "Team", "Pts", "GD", "GF", "GA");


    for(i = 0; i < MAX_TEAMS; i++){
        printf("  %4d | %-4s | %-4d | %-+4d | %-4d | %-4d |\n",
        i + 1,
        team_list[i].name,
        team_list[i].points,
        team_list[i].goalsFor - team_list[i].goalsAgainst,
        team_list[i].goalsFor,
        team_list[i].goalsAgainst);
    }
}