#include "command.h"
#include "lslib.h"

#include <ctype.h>
#include <stdlib.h>

static struct {
    bool newlines;
    bool words;
    bool characters;
    bool bytes;
    bool longest_line;
    bool has_flags;
} flags;

static int lines = 0;
static int words = 0;
static int chars = 0;
static int bytes = 0;
static int logst = 0;

static void list(int l, int w, int c, int b, int lg) {
    if (flags.newlines) {
        printf("\t%d", l);
    }
    if (flags.words) {
        printf("\t%d", w);
    }
    if (flags.characters) {
        printf("\t%d", c);
    }
    if (flags.bytes) {
        printf("\t%d", b);
    }
    if (flags.longest_line) {
        printf("\t%d", lg);
    }
}

#define BS 1024

static bool is_delimiter(char c) {
    return c == ' ' || c == '\t' || c == '\n';
}

static void run_wc(FILE* file) {
    int l = 0, w = 0, c = 0, b = 0, lg = 0;

    bool in_word = false;
    int current_length = 0;

    int read;
    char buf[BS];
    while ((read = fread(buf, 1, 1024, file)) > 0) {
        int i;
        for (i = 0; i < read; i++) {
            char ch = buf[i];
            b++;
            if (ch == '\n') { 
                l++;
                lg = lg > current_length ? lg : current_length;
                current_length = 0;
            } else {
                current_length++;
            }
            if (isprint(ch) || is_delimiter(ch)) c++;
            if (in_word && is_delimiter(ch)) {
                in_word = false;
                w++;
            } else if (!in_word && !is_delimiter(ch) && isprint(ch)) {
                in_word = true;
            }
        }
    }
    if (in_word) w++;
    lg = lg > current_length ? lg : current_length;
    list(l, w, c, b, lg);
    lines += l;
    words += w;
    chars += c;
    bytes += b;
    logst += lg;
    if (file != stdin)
        fclose(file);
}

static void help(void) {
    printf("Usage: wc [-cmlwL] [FILE]...\n\n");
    printf("Count lines, words, and bytes for FILEs (or stdin)\n\n");
	printf("\t-c	Count bytes\n");
	printf("\t-m	Count characters\n");
	printf("\t-l	Count newlines\n");
	printf("\t-w	Count words\n");
	printf("\t-L	Print longest line length\n");
    exit(EXIT_SUCCESS);
}

static int short_arg(char c, char* next) {
    UNUSED(next);
    switch (c) {
        case 'c':
            flags.bytes = true;
            break;
        case 'm':
            flags.characters = true;
            break;
        case 'l':
            flags.newlines = true;
            break;
        case 'w':
            flags.words = true;
            break;
        case 'L':
            flags.longest_line = true;
            break;
        default:
            return ARG_INVALID;
    }
    flags.has_flags = true;
    return ARG_UNUSED;
}

COMMAND(wc) {

    int start, i;

    flags.newlines = false;
    flags.words = false;
    flags.characters = false;
    flags.bytes = false;
    flags.longest_line = false;
    flags.has_flags = false;


    start = parse_args(argc, argv, help, short_arg, NULL);

    if (!flags.has_flags) {
        flags.newlines = true;
        flags.words = true;
        flags.characters = true;
    }

    if (argc - start < 1) {
        run_wc(stdin);
        printf("\n");
        return EXIT_SUCCESS;
    }

    for (i = start; i < argc; i++) {
        FILE* file = get_file(argv[i], "r");
        run_wc(file);
        printf("\t%s\n", argv[i]);
    }

    if (argc - start > 1) {
        list(lines, words, chars, bytes, logst);
        printf("\ttotal\n");
    }

    return EXIT_SUCCESS;
}