/*
 * Copyright (C) 2024 Johnny Richard <johnny@johnnyrichard.com>
 *
 * SPDX-License-Identifier: LGPL-3.0-or-later
 *
 * This file is part of obe.
 *
 * obe is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option)
 * any later version.
 *
 * obe is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with obe. If not, see <https://www.gnu.org/licenses/>.
 */
#include <config.h>
#include <obe/parser.h>
#include <obe/x86_64/codegen.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct obe_cli_args
{
    int argc;
    char** argv;
} obe_cli_args_t;

typedef struct obe_cli_opts
{
    uint32_t options;
    char* ir_file;
    char* program_path;
} obe_cli_opts_t;

typedef enum
{
    OBE_CLI_OPT_HELP = 1,
    OBE_CLI_OPT_VERSION = 1 << 1,
    OBE_CLI_OPT_OUTPUT = 1 << 2,
} cli_opt_t;

obe_cli_opts_t
obe_cli_parse_args(int argc, char** argv);

static char*
obe_cli_args_shift(obe_cli_args_t* args)
{
    if (args->argc == 0)
        return NULL;
    --(args->argc);
    return *(args->argv)++;
}

void
obe_cli_print_usage(FILE* stream)
{
    fprintf(stream,
            "Usage: " PACKAGE_NAME " [OPTIONS] file...\n"
            "\n"
            "Options:\n"
            "  -h, --help    display the help and exit\n"
            "  -v, --version output version information and exit\n"
            "  -o, --output  output gas assembly\n"
            "\n"
            "Report bugs to " PACKAGE_BUGREPORT "\n");
}

void
obe_cli_print_version(void)
{
    printf(PACKAGE_STRING
           "\n"
           "\n"
           "Copyright (C) 2025 Olang project.\n"
           "This is free software; see the source for copying conditions.  "
           "There is NO\n"
           "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR "
           "PURPOSE.\n"
           "\n"
           "Written by Johnny Richard <johnny@johnnyrichard.com>\n");
}

int
main(int argc, char** argv)
{
    obe_cli_opts_t opts = { 0 };
    obe_cli_args_t args = { .argc = argc, .argv = argv };

    opts.program_path = obe_cli_args_shift(&args);

    char* arg = obe_cli_args_shift(&args);
    while (arg != NULL) {
        if (strcmp(arg, "-h") == 0 || strcmp(arg, "--help") == 0) {
            opts.options |= OBE_CLI_OPT_HELP;
        } else if (strcmp(arg, "-v") == 0 || strcmp(arg, "--version") == 0) {
            opts.options |= OBE_CLI_OPT_VERSION;
        } else if (strcmp(arg, "-o") == 0 || strcmp(arg, "--output") == 0) {
            opts.options |= OBE_CLI_OPT_OUTPUT;
        } else {
            opts.ir_file = arg;
        }
        arg = obe_cli_args_shift(&args);
    }

    if (opts.ir_file != NULL) {
        obe_arena_t arena = { 0 };

        obe_lexer_t lexer = { 0 };
        obe_lexer_init(&lexer, opts.ir_file);

        obe_parser_t parser = { 0 };
        obe_parser_init(&parser, &lexer, &arena);
        obe_ir_translation_unit_t* tu = obe_parser_parse(&parser);

        obe_x86_64_codegen_emit(tu, stdout);
        return EXIT_SUCCESS;
    }

    if (opts.options & OBE_CLI_OPT_HELP) {
        obe_cli_print_usage(stdout);
        return EXIT_SUCCESS;
    }

    if (opts.options & OBE_CLI_OPT_VERSION) {
        obe_cli_print_version();
        return EXIT_SUCCESS;
    }

    if (opts.options & OBE_CLI_OPT_OUTPUT) {
        return EXIT_SUCCESS;
    }

    obe_cli_print_usage(stderr);
    return EXIT_FAILURE;
}