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// 
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using System.IO;
using NUnit.Framework;
using System;
using NUnit.Framework.Internal;
using Duplicati.Library.DynamicLoader;

namespace Duplicati.UnitTest
{
    public class Issue6200 : BasicSetupHelper
    {
        [Test]
        [Category("Targeted")]
        public void VerifyMultiVolumeCompactWorks()
        {
            const int FILESIZE = 500 * 1024;
            const int FILECOUNT = 40;

            var testopts = TestOptions.Expand(new
            {
                keep_versions = 1,
                no_auto_compact = true,
                zip_compression_level = 0,
                asynchronous_upload_limit = 1,
                blocksize = "100kb",
                dblock_size = "1mb"
            });

            var rnd = Random.Shared;
            // Create 100 files of 10MB each
            for (var i = 0; i < FILECOUNT; i++)
            {
                var data = new byte[FILESIZE];
                rnd.NextBytes(data);
                File.WriteAllBytes(Path.Combine(DATAFOLDER, $"a{i}"), data);
            }

            // Make a backup
            using (var c = new Library.Main.Controller("file://" + TARGETFOLDER, testopts, null))
                TestUtils.AssertResults(c.Backup(new string[] { DATAFOLDER }));

            // Delete half the files
            for (var i = 0; i < FILECOUNT / 2; i++)
                File.Delete(Path.Combine(DATAFOLDER, $"a{i}"));

            // Make a backup
            using (var c = new Library.Main.Controller("file://" + TARGETFOLDER, testopts, null))
                TestUtils.AssertResults(c.Backup(new string[] { DATAFOLDER }));

            var fullBlockvolumeCount = Directory.GetFiles(TARGETFOLDER, "*.dblock.*", SearchOption.TopDirectoryOnly).Length;

            // Now run compact
            using (var c = new Library.Main.Controller("file://" + TARGETFOLDER, testopts, null))
                TestUtils.AssertResults(c.Compact());

            var newBlockvolumeCount = Directory.GetFiles(TARGETFOLDER, "*.dblock.*", SearchOption.TopDirectoryOnly).Length;

            // Check that the number of dblock files is reduced by at least 4
            Assert.That(newBlockvolumeCount, Is.LessThan(fullBlockvolumeCount - 4), "Compact did not reduce the number of dblock files");

            BackendLoader.AddBackend(new DeterministicErrorBackend());
            File.Delete(DBFILE);

            DeterministicErrorBackend.ErrorGenerator = (action, remotename) =>
            {
                if (action.IsGetOperation && remotename.Contains(".dblock."))
                    return true;
                return false;
            };

            using (var c = new Library.Main.Controller(new DeterministicErrorBackend().ProtocolKey + "://" + TARGETFOLDER, testopts, null))
                TestUtils.AssertResults(c.Repair());
        }
    }
}