// Copyright (c) 2025 TerraByte Inc.
//
// A static class that persists the state of a multi-file reset operation
// across script re-compilations, ensuring the process is not interrupted.

using System.Linq;
using UnityEditor;

namespace Terra.Arbitrator.Services
{
    [InitializeOnLoad]
    public static class BetterGitStatePersistence
    {
        internal const string ResetQueueKey = "BetterGit.ResetQueue";

        // This static constructor runs automatically after every script compilation.
        static BetterGitStatePersistence()
        {
            // Use delayCall to ensure this runs after the editor is fully initialized.
            EditorApplication.delayCall += ContinueInterruptedReset;
        }

        public static void ContinueInterruptedReset()
        {
            while (true)
            {
                var queuedFiles = SessionState.GetString(ResetQueueKey, "");
                if (string.IsNullOrEmpty(queuedFiles))
                {
                    return; // Nothing to do.
                }

                var fileList = queuedFiles.Split(';').ToList();
                if (!fileList.Any())
                {
                    SessionState.EraseString(ResetQueueKey);
                    return;
                }

                // Get the next file to process
                var fileToReset = fileList.First();
                fileList.RemoveAt(0);

                // Update the session state with the remaining files BEFORE starting the operation.
                if (fileList.Any())
                {
                    SessionState.SetString(ResetQueueKey, string.Join(";", fileList));
                }
                else
                {
                    // Last file was processed, clear the key.
                    SessionState.EraseString(ResetQueueKey);
                }

                // Create a GitChange object for the file to be reset.
                // This is a small, synchronous operation to get the file's current status.
                var change = GitService.GetChangeForFile(fileToReset);
                if (change == null)
                {
                    // The File might have already been reset or state is unusual.
                    // We'll log it and attempt to continue.
                    UnityEngine.Debug.LogWarning($"Could not find status for {fileToReset}, skipping reset. It may have already been processed.");
                    continue;
                }

                // Trigger the reset. After this, Unity will recompile if it was a script,
                // and this whole static constructor will run again.
                GitService.ResetFileChanges(change);
                break;
            }
        }
    }
}