#include <ctype.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>

#define NOB_IMPLEMENTATION
#include "nob.h"

typedef enum e_Token_Kind {
    TOKEN_KIND_PAR_LEFT,
    TOKEN_KIND_PAR_RIGHT,
    TOKEN_KIND_NUMBER,
    TOKEN_KIND_SYMBOL,
} TokenKind;

typedef struct s_Token {
    TokenKind kind;
    Nob_String_View data;
} Token;

typedef struct s_Tokens {
    Token *items;
    size_t count;
    size_t capacity;
} Tokens;

void tokenize(Nob_String_View content, Tokens *tokens) {
    for (size_t i = 0; i < content.count; i++) {
        char c = content.data[i];

        int kind = -1;
        switch (c) {
        case '(': {
            kind = TOKEN_KIND_PAR_LEFT;
        } break;
        case ')': {
            kind = TOKEN_KIND_PAR_RIGHT;
        } break;
        }

        if (kind != -1) {
            Token tok = (Token){.kind = kind, .data = {0}};
            nob_da_append(tokens, tok);
            continue;
        }

        Nob_String_Builder sb = {0};
        while (isdigit(c)) {
            nob_sb_appendf(&sb, "%c", c);
            c = content.data[++i];
        }

        if (sb.count > 0) {
            i--;

            Token tok =
                (Token){.kind = TOKEN_KIND_NUMBER, .data = nob_sb_to_sv(sb)};
            nob_da_append(tokens, tok);
            continue;
        }

        // symbols shouldn't start with a digit
        bool condition =
            isascii(c) && !isdigit(c) && !isblank(c) && c != '(' && c != ')';
        while (condition) {
            nob_sb_appendf(&sb, "%c", c);
            c = content.data[++i];
            condition = isascii(c) && !isblank(c) && c != '(' && c != ')';
        }

        if (sb.count > 0) {
            i--;

            Token tok =
                (Token){.kind = TOKEN_KIND_SYMBOL, .data = nob_sb_to_sv(sb)};
            nob_da_append(tokens, tok);
        }
    }
}

const char *token_kind_name(TokenKind kind) {
    switch (kind) {
    case TOKEN_KIND_PAR_LEFT:
        return "PAR_LEFT";
    case TOKEN_KIND_PAR_RIGHT:
        return "PAR_RIGHT";
    case TOKEN_KIND_NUMBER:
        return "NUMBER";
    case TOKEN_KIND_SYMBOL:
        return "SYMBOL";
    default:
        UNREACHABLE("Unknown token type");
    }
}

int main(int argc, char **argv) {
    if (argc < 2)
        return 1;

    argv++;
    const char *line = *argv++;
    Nob_String_View view = nob_sv_from_cstr(line);

    Tokens tokens = {0};
    tokenize(view, &tokens);

    for (size_t i = 0; i < tokens.count; i++) {
        Token tok = tokens.items[i];
        printf("Token(kind=%s, data=" SV_Fmt ")\n", token_kind_name(tok.kind),
               SV_Arg(tok.data));
    }

    return 0;
}