BTCPayServerPlugins/Plugins/BTCPayServer.Plugins.Prism/Components/PrismSplit.razor

<div class="border border-light p-2 m-1">
    <div class="form-group">
        <label class="form-label">Source</label>
        <input type="text" @bind="Split.Source" list="users" class="form-control src"/>
        <ValidationMessage2 For="() => Split.Source" class="text-danger"></ValidationMessage2>
    </div>
    <table class="table mb-0">
        <thead>
        <tr>
            <th>
                Destination
            </th>
            <th> Percentage</th>
            <th> Actions</th>
        </tr>
        </thead>
        <tbody>
        @foreach (var destination in Split.Destinations)
        {
            <tr>
                <td>
                    <input type="text" @bind="@destination.Destination" list="destinations" class="form-control dest"/>

                    <ValidationMessage2 For="() => destination.Destination" class="text-danger"></ValidationMessage2>
                </td>
                <td>
                    <input type="range" value="@destination.Percentage" @oninput="@((e) => UpdateDestinationValue(destination, e.Value))" min="0" step='0.01' class="form-range" max="100"/>
                    <div class="input-group input-group-sm">
                        <input type="number" step='0.01' value="@destination.Percentage" @onchange="@((e) => UpdateDestinationValue(destination, e.Value))" class="form-control form-control-sm"/>
                        <span class="input-group-text">%</span>
                    </div>

                    <ValidationMessage2 For="() => destination.Percentage" class="text-danger"></ValidationMessage2>
                </td>
                <td>
                    <button class="btn btn-link remove-dest btn-danger" type="button" @onclick="@(() => Split.Destinations.Remove(destination))">Remove</button>
                </td>
            </tr>
        }
        </tbody>
        <tfoot>
        @if (Split.Destinations.Count > 1)
        {
            <tr>
                <td colspan="3">
                    Sending @(100 - Leftover)% to @Split.Destinations.Count destinations
                </td>
            </tr>
        }
        <tr>
            <td colspan="3">
                <button class="btn btn-link add-dest" type="button" @onclick="CreateDestination">Add</button>
                <button class="btn btn-link remove-prism" type="button" @onclick="RemoveSplit">Remove Prism</button>
            </td>
        </tr>
        </tfoot>
    </table>
</div>

@code {
    [CascadingParameter]
    private EditContext CascadedEditContext { get; set; }

    public decimal Leftover => 100 - Split.Destinations.Sum(split => split.Percentage);

    [Parameter]
    public Split Split { get; set; }

    [Parameter]
    public EventCallback<Split> OnRequestRemove { get; set; }

    private void CreateDestination()
    {
        Split.Destinations.Add(new Prism.PrismSplit());
    }

    private void RemoveSplit()
    {
        OnRequestRemove.InvokeAsync(Split);
    }

    private void UpdateDestinationValue(Prism.PrismSplit destination, object eValue)
    {
        var newValue = Math.Min(100, Math.Round(Convert.ToDecimal(eValue), 2));

        var allowedMax = Math.Round(destination.Percentage + Leftover, 2);

        if (newValue > allowedMax)
        {
            //take the difference from the other destinations proportionally
            var difference = Math.Round(newValue - allowedMax, 2);
            var otherDestinations = Split.Destinations.Where(split => split != destination).ToList();
            var totalPercentage = Math.Round(otherDestinations.Sum(split => split.Percentage), 2);
            foreach (var otherDestination in otherDestinations)
            {
                var percentage = otherDestination.Percentage;
                var newPercentage = Math.Round(percentage - (percentage / totalPercentage * difference), 2);
                otherDestination.Percentage = newPercentage;
            }
        }
        destination.Percentage = newValue;
    }

}