CommentSection.razor

@using ContosoSnsWebApp.Models
@using ContosoSnsWebApp.Services
@inject ApiService ApiService

<div class="mt-4">
    <h4 class="mb-3">댓글 (@(comments?.Count ?? 0))</h4>

    @if (isLoading)
    {
        <p>댓글 로딩 중...</p>
    }
    else if (!string.IsNullOrEmpty(loadError))
    {
         <div class="alert alert-warning">@loadError</div>
    }
    else if (comments == null || comments.Count == 0)
    {
        <p class="text-muted">아직 댓글이 없습니다.</p>
    }
    else
    {
        <div class="list-group list-group-flush mb-3">
            @foreach (var comment in comments.OrderByDescending(c => c.CreatedAt))
            {
                <div class="list-group-item px-0">
                    <div class="d-flex w-100 justify-content-between">
                        <h6 class="mb-1">@comment.UserName</h6>
                        <small class="text-muted">@FormatDate(comment.CreatedAt)</small>
                    </div>
                    <p class="mb-1">@comment.Content</p>
                </div>
            }
        </div>
    }

    <EditForm Model="newCommentRequest" OnValidSubmit="HandleCommentSubmitAsync" FormName="newCommentForm">
        <DataAnnotationsValidator />
        <div class="mb-2">
            <InputTextArea @bind-Value="newCommentRequest.Content" class="form-control" rows="2" placeholder="댓글을 입력하세요..." required />
            <ValidationMessage For="@(() => newCommentRequest.Content)" />
        </div>
         @if (!string.IsNullOrEmpty(submitError))
        {
            <div class="alert alert-danger mt-2 py-1">@submitError</div>
        }
        <Button Type="submit" Variant="secondary" Small="true" Disabled="isSubmitting">
            @(isSubmitting ? "등록 중..." : "댓글 등록")
        </Button>
    </EditForm>
</div>

@code {
    [Parameter, EditorRequired] public int PostId { get; set; }
    [Parameter] public string? UserName { get; set; } // Current user's name

    private List<Comment>? comments;
    private NewCommentRequest newCommentRequest = new("", "");
    private bool isLoading = true;
    private bool isSubmitting = false;
    private string? loadError = null;
    private string? submitError = null;

    protected override async Task OnInitializedAsync()
    {
        await LoadCommentsAsync();
        if (!string.IsNullOrEmpty(UserName))
        {
            // newCommentRequest = newCommentRequest with { UserName = UserName };
            newCommentRequest.UserName = UserName; // Ensure username is set
        }
    }

     protected override async Task OnParametersSetAsync()
    {
        // Reload comments if PostId changes
        // This might happen if the modal is reused without full disposal
        if (PostId > 0 && (comments == null || comments.All(c => c.PostId != PostId)))
        {
             await LoadCommentsAsync();
        }

        // Update username for new comment if it changes
        if (!string.IsNullOrEmpty(UserName) && newCommentRequest.UserName != UserName)
        {
            // newCommentRequest = newCommentRequest with { UserName = UserName };
            newCommentRequest.UserName = UserName; // Ensure username is set
        }
    }

    private async Task LoadCommentsAsync()
    {
        if (PostId <= 0) return;

        isLoading = true;
        loadError = null;
        StateHasChanged();
        try
        {
            comments = await ApiService.GetCommentsAsync(PostId);
        }
        catch (Exception ex)
        {
            Console.Error.WriteLine($"Error loading comments: {ex.Message}");
            loadError = "댓글을 불러오는 데 실패했습니다.";
        }
        finally
        {
            isLoading = false;
            StateHasChanged();
        }
    }

    private async Task HandleCommentSubmitAsync()
    {
        if (isSubmitting || PostId <= 0 || string.IsNullOrWhiteSpace(UserName))
        {
            submitError = "사용자 이름이 필요합니다."; // Should ideally not happen if UserName is passed correctly
            return;
        }

        isSubmitting = true;
        submitError = null;
        StateHasChanged();

        // newCommentRequest = newCommentRequest with { UserName = UserName }; // Ensure username is set
        newCommentRequest.UserName = UserName; // Ensure username is set

        try
        {
            var createdComment = await ApiService.CreateCommentAsync(PostId, newCommentRequest);
            if (createdComment != null)
            {
                comments ??= [];
                comments.Add(createdComment);
                newCommentRequest = new(UserName, ""); // Reset content, keep username
            }
            else
            {
                submitError = "댓글 등록에 실패했습니다.";
            }
        }
        catch (Exception ex)
        {
            Console.Error.WriteLine($"Error submitting comment: {ex.Message}");
            submitError = "댓글 등록 중 오류가 발생했습니다.";
        }
        finally
        {
            isSubmitting = false;
            StateHasChanged();
        }
    }

    private string FormatDate(DateTime? date)
    {
        // More detailed format for comments might be nice
        return date?.ToString("yyyy-MM-dd HH:mm") ?? string.Empty;
    }
}