@page "/GitLog"
@using System.Web
@using LibGit
@using LibGit.Extensions
<h3>GitLog</h3>
<p>Repo: @Repo</p>

@if (heads.Count > 0)
{
    <p>
        Revision:
        <details>
            <summary>@Rev</summary>
        </details>
    </p>
}

@if (commits != null)
{
    <table class="table">
        <thead>
        <tr>
            <th>Heads</th>
            <th>Commit</th>
            <th>Author</th>
            <th>Message</th>
        </tr>
        </thead>
        <tbody>
            @foreach (var commit in commits)
            {
                <tr>
                    <td>
                        @foreach (var _ref in heads.Where(x=>x.CommitId == commit.CommitId))
                        {
                            <p>@_ref.Name</p>
                        }
                    </td>
                    <td>@commit.CommitId[..7]</td>
                    <td>@commit.AuthorName</td>
                    <td>@commit.Message</td>
                </tr>
            }
        </tbody>
    </table>
}

@code {

    string? Repo { get; set; }
    string? Rev { get; set; }
    
    List<CommitObject> commits = new();
    List<GitRef> heads = new();

    protected override async Task OnInitializedAsync()
    {
        var query = new Uri(NavigationManager.Uri).Query;
        var queryDictionary = HttpUtility.ParseQueryString(query);
        if((Repo = queryDictionary["repo"]) == null)
        {
            return;
        }
        
        var repo = new GitRepo(new WebRepoSource(queryDictionary["repo"])
        {
            SessionStorage = sessionStorage
        });
        
        if((Rev = queryDictionary["rev"]) == null)
        {
            Rev = "HEAD";
        }

        var ss = new SemaphoreSlim(2,2);
        
        var _heads = repo.GetRefs().GetAsyncEnumerator();
        while (await _heads.MoveNextAsync())
        {
            heads.Add(_heads.Current);
            var isCached = await ((WebRepoSource)repo.RepoSource).HasObjectCached(_heads.Current.CommitId);
            Console.WriteLine(_heads.Current.Name+ " - cache miss: " + !isCached);
            if (!isCached)
            {

                var _c = _heads.Current.CommitId;
#pragma warning disable CS4014
                Task.Run(async () =>
#pragma warning restore CS4014
                {
                    await ss.WaitAsync();
                    Console.WriteLine("hi from task");
                    var a = new GitRepo(new WebRepoSource(queryDictionary["repo"])
                    {
                        SessionStorage = sessionStorage
                    }).GetCommits(_c).GetAsyncEnumerator();
                    while (
                        await a.MoveNextAsync() 
                        && !await ((WebRepoSource)repo.RepoSource)
                            .HasObjectCached(a.Current.CommitId)
                    ) Console.WriteLine($"Prefetched commit {a.Current.CommitId} with {a.Current.ParentIds.Count()} parents");
                    Console.WriteLine($"Reached already-cached log: {a.Current.CommitId}");
                    ss.Release();
                });
            }
        }
        

        var log = repo.GetCommits(heads.First(x=>x.Name == Rev).CommitId).GetAsyncEnumerator();
        while (await log.MoveNextAsync())
        {
            commits.Add(log.Current);
            if (commits.Count % 50 == 0)
            {
                StateHasChanged();
                await Task.Delay(1);
            }
        }
        
    }
}