#include <ncurses.h>
#include "hangman.h"
#include <stdlib.h> //atexit
#include <string.h>
#include <ctype.h> //tolower
#include <getopt.h>
#include <time.h>
#include "prng.h"

int main(int argc, char **argv) {
  
    const char *short_options = "w:hf:c";
    struct option long_options[] = {
        {"word", required_argument, NULL, 'w'},
        {"help", no_argument, NULL, 'h'},
        {"file", required_argument, NULL, 'f'},
        {"credits", no_argument, NULL, 'c'}
    };  
    int c, startscr = 1; /* Show startscreen by default */
    char *filename;

    //while ( (c = getopt_long(argc, argv, short_options, long_options, NULL)) != -1 ) 
    
    /* Initialization */
    initscr();
    atexit(quitProgram);
    game_state *gs;
    gs = malloc(sizeof(game_state));
    initCoordinates(gs);
    gs->allowedMoves = DEFAULTTRIES;
    gs->moves = 0;
    gs->guesses = 0;
    
    
    curs_set(0); 
    while ( (c = getopt_long(argc, argv, short_options, long_options, NULL)) != -1 ) {
        switch (c) {
        case 'w':
            sprintf(gs->guessWord, "%s", optarg);
            startscr = 0;
            break;
        case 'h':
            showHelp(gs);
            exit(0);
            break;
        case 'f':
            /* Set filename */
            filename = optarg;
            startscr = 0;
            break;
        case 'c':

            break;
        default:

            break;
        }
    }
    InitializePRNG(time(NULL)); /* Initialize random number generator */
    
    if (startscr) {
        showStartScreen(gs);
    }

    /* start game */
    initGuessWord(gs, filename);
    
    startGame(gs);
    

    getch();
    free(gs);
    return 0;
}

void startGame(game_state *gs) {
    noecho(); /* Don't show the player input */
    while (checkWin(gs)) {
        updateScreen(gs);
        playerInput(gs);
    }

}


void quitProgram(void) {
    endwin();
}

void showStartScreen(game_state *gs) {
    mvprintw(gs->centery - 1, gs->centerx - 15, "Welcome to hangman in ncurses.");
    mvprintw(gs->centery, gs->centerx - 5, "Have fun!");
    mvprintw(gs->centery + 1, gs->centerx - 17, "https://gitlab.com/STRUCTiX/hangman");
    refresh();
    getch();
    clear();
}

void updateScreen(game_state *gs) {
    mvprintw(1, 1, "Remaining wrong guesses: %i", (gs->allowedMoves - gs->moves));
    mvprintw(gs->maxy - 1, 1, "Press ctrl + c to exit.");
    drawGuessWord(gs);
    mvprintw(2, 1, "Wrong characters: %s", gs->wrongCharacters);
    refresh();
}

void initCoordinates(game_state *gs) {
    getmaxyx(stdscr, gs->maxy, gs->maxx);
    gs->centery = gs->maxy / 2;
    gs->centerx = gs->maxx / 2;
}

void initGuessWord(game_state *gs, char *filename) {
    int i;
    mvprintw(1, 1, "Please enter your word: ");
    if (strlen(gs->guessWord) == 0) { /* Word can be set by arguments */
        if (strlen(filename) == 0) {
            /* Manual input */
            curs_set(1);
            getstr(gs->guessWord);
            curs_set(0);
        } else {
            /* Random line from file */
            readRandomLine(filename, gs->guessWord);
        }
            
    }

    /* Make String all lowercase */
    toLowerCase(gs->guessWord);
    gs->wordLength = strlen(gs->guessWord);

    for (i = 0; i < gs->wordLength; i++) {
        if (gs->guessWord[i] == ' ') { //Check for spaces if it's a sentence
            gs->currentWord[i] = ' ';
        } else {
            gs->currentWord[i] = '_';
        }
    }
    clear(); //clear the screen
}

void toLowerCase(char *str) {
    int length = strlen(str);
    int i;
    for (i = 0; i < length; i++) {
        str[i] = tolower(str[i]);
    }
}

void drawGuessWord(game_state *gs) {
    int startpos = gs->centerx - gs->wordLength;
    int i, wordpos = 0;
    int switchspace = 0;
    for (i = startpos; i < startpos + (gs->wordLength * 2); i++) {
        if (switchspace) {
            /* this will place a space */
            mvprintw(gs->centery, i, " ");
            switchspace = 0;
        } else {
            mvprintw(gs->centery, i, "%c", gs->currentWord[wordpos++]);
            switchspace = 1;
        }
    }
    refresh();
}

int playerInput(game_state *gs) {
    char inp;
    int i, found = 0;
    inp = getch();
    
    for (i = 0; i < gs->wordLength; i++) {
        if (inp == gs->guessWord[i]) {
            found = 1;
            break;
        }
    }
    if (found) {
        /* found a valid character */
        if (fillCurrentWord(gs, inp)) {
            //gs->moves++;
            gs->guesses++;
        }
    } else {
        /* no valid character found */
        if (stackWrongCharacter(gs, inp)) {
            gs->moves++;
            gs->guesses++;
        }
    }
    return 0;
}

int fillCurrentWord(game_state *gs, char validchar) {
    int i, alreadyUsed = 0;
    for (i = 0; i < gs->wordLength; i++) {
        if (gs->currentWord[i] == validchar) {
            alreadyUsed = 1;
            break;
        }
    }
    if (!alreadyUsed) {        
        for (i = 0; i < gs->wordLength; i++) {
            if (gs->guessWord[i] == validchar) {
                gs->currentWord[i] = validchar;
            }
        }
        return 1;
    } else {
        return 0;
    }
}

int stackWrongCharacter(game_state *gs, char wrongchar) {
    int i, alreadyUsed = 0;
    for (i = 0; i < gs->wordLength; i++) {
        if (gs->wrongCharacters[i] == wrongchar) {
            alreadyUsed = 1;
        }
    }
    
    if (!alreadyUsed) {
        gs->wrongCharacters[strlen(gs->wrongCharacters)] = wrongchar;
        return 1;
    } else {
        return 0;
    }
}

int checkWin(game_state *gs) {
    if (strcmp(gs->guessWord, gs->currentWord) != 0 && gs->moves < gs->allowedMoves) {
        /* next move */
        return 1;
    } else {
        /* game end: decide if game is won or lost */
        printGameStats(gs);
        return 0;
    }
}

void printGameStats(game_state *gs) {
    clear();
    if (gs->moves >= gs->allowedMoves) {
        mvprintw(gs->centery, gs->centerx - 10, "Game lost. Solution:");
        mvprintw(gs->centery + 1, gs->centerx - (gs->wordLength / 2), gs->guessWord);
    } else {
        char message[100];
        sprintf(message, "Game won! Total guesses: %i", gs->guesses);
        mvprintw(gs->centery, gs->centerx - (strlen(message) / 2), message);
    }
    refresh();
}
        
void showHelp(game_state *gs) {
    char *wordstring = "-w or --word: Enter the word or sentence as an argument";
    char *helpstring = "-h or --help: Show this page";
    mvprintw(gs->centery, centerDiff(gs->centerx, wordstring), wordstring);
    mvprintw(gs->centery + 1, centerDiff(gs->centerx, helpstring), helpstring);
    getch();
}

int centerDiff(int coordinate, char *str) {
    int len = strlen(str);
    return coordinate - (len / 2); /* Integer division */
}

void readRandomLine(char *file, char *result) {
    long totalLength = 0, rand = 0;
    FILE *fp = fopen(file, "r");
    char c;

    while ((c = fgetc(fp)) != EOF) {
        if (c == '\n') ++totalLength;
    }
    
    rand = getrandom(0, totalLength);
    fseek(fp, rand, SEEK_SET);

    fgets(result, MAXWORDLENGTH, fp);

    fclose(fp);
}