using Microsoft.SharePoint.Client;
using Serilog;
using SharepointToolbox.Web.Core.Helpers;
using SharepointToolbox.Web.Core.Models;
using SharepointToolbox.Web.Services.Audit;

namespace SharepointToolbox.Web.Services;

public class FolderStructureService : IFolderStructureService
{
    private readonly IAuditService _audit;

    public FolderStructureService(IAuditService audit) { _audit = audit; }

    public async Task<BulkOperationSummary<string>> CreateFoldersAsync(
        ClientContext ctx, string libraryTitle,
        IReadOnlyList<FolderStructureRow> rows,
        IProgress<OperationProgress> progress, CancellationToken ct)
    {
        var list = ctx.Web.Lists.GetByTitle(libraryTitle);
        ctx.Load(list, l => l.RootFolder.ServerRelativeUrl);
        await ExecuteQueryRetryHelper.ExecuteQueryRetryAsync(ctx, progress, ct);
        var baseUrl = list.RootFolder.ServerRelativeUrl.TrimEnd('/');
        var folderPaths = BuildUniquePaths(rows);

        var result = await BulkOperationRunner.RunAsync(
            folderPaths,
            async (path, idx, token) =>
            {
                ctx.Web.Folders.Add($"{baseUrl}/{path}");
                await ExecuteQueryRetryHelper.ExecuteQueryRetryAsync(ctx, progress, token);
                Log.Information("Created folder: {Path}", $"{baseUrl}/{path}");
            },
            progress, ct);
        await _audit.LogAsync("CreateFolderStructure", ctx.Url, new[] { ctx.Url },
            $"{result.SuccessCount} folders created in '{libraryTitle}', {(result.TotalCount - result.SuccessCount)} failed");
        return result;
    }

    internal static IReadOnlyList<string> BuildUniquePaths(IReadOnlyList<FolderStructureRow> rows)
    {
        var paths = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        foreach (var row in rows)
        {
            var parts = new[] { row.Level1, row.Level2, row.Level3, row.Level4 }
                .Where(s => !string.IsNullOrWhiteSpace(s)).ToArray();
            var current = string.Empty;
            foreach (var part in parts)
            {
                current = string.IsNullOrEmpty(current) ? part.Trim() : $"{current}/{part.Trim()}";
                paths.Add(current);
            }
        }
        return paths.OrderBy(p => p.Count(c => c == '/')).ThenBy(p => p, StringComparer.OrdinalIgnoreCase).ToList();
    }
}