/*
 * pkg - Package locker
 * https://rawnix.org
 *
 * Copyright (c) 2025 zorz@gmx.com
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "locker.h"
#include "paths.h"
#include <fcntl.h>
#include <unistd.h>

struct locker {
    char       *path;
    strarray_t  pkgs;
};

locker_t *locker_open(const char *root)
{
    locker_t *l;
    FILE     *fp;
    char      line[256];

    l = xmalloc(sizeof(locker_t));
    strarray_init(&l->pkgs);
    l->path = build_root_path(root, LOCK_FILE);

    fp = fopen(l->path, "r");
    if (!fp)
        return l;

    while (fgets(line, sizeof(line), fp)) {
        line[strcspn(line, "\n")] = '\0';
        if (line[0] && line[0] != '#')
            strarray_add(&l->pkgs, line);
    }

    fclose(fp);
    return l;
}

void locker_close(locker_t *l)
{
    if (!l)
        return;
    strarray_free(&l->pkgs);
    free(l->path);
    free(l);
}

static int locker_save(locker_t *l)
{
    char  tmp[4096];
    int   fd;
    FILE *fp;
    size_t i;

    ensure_parent_dir(l->path);

    snprintf(tmp, sizeof(tmp), "%s.tmp", l->path);

    fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 0644);
    if (fd < 0)
        return -1;

    fp = fdopen(fd, "w");
    if (!fp) {
        close(fd);
        unlink(tmp);
        return -1;
    }

    fprintf(fp, "# Locked packages (excluded from sysup)\n");
    for (i = 0; i < l->pkgs.size; i++)
        fprintf(fp, "%s\n", l->pkgs.data[i]);

    if (file_close_checked(fp) != 0) {
        unlink(tmp);
        return -1;
    }

    if (rename(tmp, l->path) != 0) {
        unlink(tmp);
        return -1;
    }

    return 0;
}

bool locker_is_locked(locker_t *l, const char *pkg)
{
    return strarray_contains(&l->pkgs, pkg);
}

bool locker_lock(locker_t *l, const char *pkg)
{
    if (locker_is_locked(l, pkg))
        return true;
    strarray_add(&l->pkgs, pkg);
    return locker_save(l) == 0;
}

bool locker_unlock(locker_t *l, const char *pkg)
{
    size_t i;

    for (i = 0; i < l->pkgs.size; i++) {
        if (strcmp(l->pkgs.data[i], pkg) == 0) {
            free(l->pkgs.data[i]);
            l->pkgs.data[i] = l->pkgs.data[--l->pkgs.size];
            return locker_save(l) == 0;
        }
    }
    return false;
}

strarray_t *locker_list(locker_t *l)
{
    strarray_t *arr;
    size_t      i;

    arr = xmalloc(sizeof(strarray_t));
    strarray_init(arr);

    for (i = 0; i < l->pkgs.size; i++)
        strarray_add(arr, l->pkgs.data[i]);

    return arr;
}