@namespace Oqtane.Modules.Controls
@inherits ModuleBase
@typeparam TableItem

<p align="center">
    <table class="table table-borderless">
        <thead>
            <tr>@Header</tr>
        </thead>
        <tbody>
            @foreach (var item in ItemList)
            {
                <tr>@Row(item)</tr>
            }
        </tbody>
    </table>
    <div>
        @if (Page > MaxPages)
        {
            <button class="btn btn-secondary" @onclick=@(async () => SetPagerSize("back"))><span class="oi oi-media-skip-backward" title="back" aria-hidden="true"></span></button>
        }
        @if (EndPage > 1)
        {
            <button class="btn btn-secondary" @onclick=@(async () => NavigateToPage("previous"))><span class="oi oi-chevron-left" title="previous" aria-hidden="true"></span></button>            
            @for (int i = StartPage; i <= EndPage; i++)
            {
                var pager = i;
                <button class="btn @((pager == Page) ? "btn-primary" : "btn-link")" @onclick=@(async () => UpdateList(pager))>
                    @pager
                </button>
            }
            <button class="btn btn-secondary" @onclick=@(async () => NavigateToPage("next"))><span class="oi oi-chevron-right" title="next" aria-hidden="true"></span></button>
        }
        @if (EndPage < Pages)
        {
            <button class="btn btn-secondary" @onclick=@(async () => SetPagerSize("forward"))><span class="oi oi-media-skip-forward" title="forward" aria-hidden="true"></span></button>
        }
        @if (EndPage > 1)
        {
            <span class="btn btn-link disabled">Page @Page of @Pages</span>
        }
    </div>
</p>

@code {
    int Pages;
    int Page;
    int MaxItems;
    int MaxPages;
    int StartPage;
    int EndPage;

    [Parameter]
    public RenderFragment Header { get; set; }

    [Parameter]
    public RenderFragment<TableItem> Row { get; set; }

    [Parameter]
    public IEnumerable<TableItem> Items { get; set; }

    [Parameter]
    public string PageSize { get; set; }

    [Parameter]
    public string DisplayPages { get; set; }

    IEnumerable<TableItem> ItemList { get; set; }

    protected override void OnInitialized()
    {
        if (string.IsNullOrEmpty(PageSize))
        {
            MaxItems = 10;
        }
        else
        {
            MaxItems = int.Parse(PageSize);
        }
        if (string.IsNullOrEmpty(DisplayPages))
        {
            MaxPages = 5;
        }
        else
        {
            MaxPages = int.Parse(DisplayPages);
        }
        Page = 1;

        ItemList = Items.Skip((Page - 1) * MaxItems).Take(MaxItems);
        Pages = (int)Math.Ceiling(Items.Count() / (decimal)MaxItems);

        SetPagerSize("forward");
    }

    public void UpdateList(int CurrentPage)
    {
        ItemList = Items.Skip((Page - 1) * MaxItems).Take(MaxItems);
        Page = CurrentPage;
        StateHasChanged();
    }

    public void SetPagerSize(string direction)
    {
        if (direction == "forward")
        {
            StartPage = EndPage + 1;
            if (EndPage + MaxPages < Pages)
            {
                EndPage = StartPage + MaxPages - 1;
            }
            else
            {
                EndPage = Pages;
            }
            StateHasChanged();
        }
        else if (direction == "back")
        {
            EndPage = StartPage - 1;
            StartPage = StartPage - MaxPages;
        }
    }

    public void NavigateToPage(string direction)
    {
        if (direction == "next")
        {
            if (Page < Pages)
            {
                if (Page == EndPage)
                {
                    SetPagerSize("forward");
                }
                Page += 1;
            }
        }
        else if (direction == "previous")
        {
            if (Page > 1)
            {
                if (Page == StartPage)
                {
                    SetPagerSize("back");
                }
                Page -= 1;
            }
        }
        UpdateList(Page);
    }
}