using System;
using System.Collections.Generic;

namespace Foodsoft.Alpm
{
    public sealed class Handle : IDisposable
    {
        private readonly SafeAlpmHandle _handle;

        public Handle(string root, string dbpath)
        {
            _handle = alpm.alpm_initialize(root, dbpath, out var err);
            if (_handle.IsInvalid) throw new AlpmException(err);
        }

        public Database LocalDB => ToDatabase(alpm.alpm_get_localdb(_handle));

        public ICollection<string> CacheDirs
        {
            get =>
                EnumerableWrapper.Create(_handle, alpm.alpm_option_get_cachedirs);
            set => Detail.SetStringCollection(value, _handle, s => alpm.alpm_option_add_cachedir(_handle, s));
        }

        public void Dispose()
        {
            _handle.Dispose();
        }

        private Database ToDatabase(IntPtr ptr)
        {
            // It's ok that the database pointer is kept outside atomic section, because the resource is actually
            // managed by the alpm handle.
            if (ptr == IntPtr.Zero) throw new AlpmException(_handle);

            return new Database(new SafeDatabaseHandle(ptr, _handle));
        }

        public Database RegisterSyncDB(string treename, SigLevel sigLevel = 0)
        {
            return ToDatabase(alpm.alpm_register_syncdb(_handle, treename, sigLevel));
        }

        public void AddCacheDir(string dir)
        {
            Detail.WrapError(_handle, () => alpm.alpm_option_add_cachedir(_handle, dir));
        }

        public bool RemoveCacheDir(string dir)
        {
            return Detail.WrapErrorBool(_handle, () => alpm.alpm_option_add_cachedir(_handle, dir));
        }

        public bool ShouldIgnorePackage(Package pkg)
        {
            return alpm.alpm_pkg_should_ignore(_handle, pkg.Handle) == 0;
        }
    }
}