#include "eval.h"
#include "lexer.h"
#include "object.h"
#include "parser.h"
#include "tokens.h"

#include <assert.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static void repl();
static void script();

int main()
{
    const bool is_tty = isatty(fileno(stdin));

    if (is_tty) {
        repl();
    } else {
        script();
    }

    exit(EXIT_SUCCESS);
}

void repl()
{
    while (true) {
        Tokens tokens = Tokens_new();
        assert(tokens);

        Lexer lexer = Lexer_new(tokens);
        assert(lexer);

        printf(">> ");

        while (true) {
            const char chr = getchar();

            if (chr == EOF) {
                putchar('\n');
                exit(EXIT_SUCCESS);
            }
            if (chr == '\n') break;

            Lexer_lex(lexer, chr);
        }

        Lexer_lex(lexer, '\n');
        LEXER_DELETE(lexer);
        if (Tokens_top(tokens) == NULL) continue;

        struct Object *const program = parse(tokens);
        TOKENS_DELETE(tokens);

        struct Object *const result = eval(program);

        printf("=> ");
        eval(Object_build_list(
            2,
            Object_new_symbol("displayln"),
            Object_build_list(2, Object_new_symbol("quote"), result)
        ));
    }
}

void script()
{
    Tokens tokens = Tokens_new();
    assert(tokens);

    Lexer lexer = Lexer_new(tokens);
    assert(lexer);

    while (true) {
        const char chr = getchar();
        if (chr == EOF) break;
        Lexer_lex(lexer, chr);
    }

    Lexer_lex(lexer, '\n');
    LEXER_DELETE(lexer);
    if (Tokens_top(tokens) == NULL) return;

    struct Object *const program = parse(tokens);
    TOKENS_DELETE(tokens);

    eval(program);
}