// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Text.Json;
using Microsoft.JSInterop;
using Microsoft.JSInterop.Infrastructure;
 
namespace Microsoft.AspNetCore.Components.WebView.Services;
 
internal sealed class WebViewJSRuntime : JSRuntime
{
    private IpcSender _ipcSender;
    private bool _disconnected;
 
    public ElementReferenceContext ElementReferenceContext { get; }
 
    public WebViewJSRuntime()
    {
        ElementReferenceContext = new WebElementReferenceContext(this);
        JsonSerializerOptions.Converters.Add(
            new ElementReferenceJsonConverter(
                new WebElementReferenceContext(this)));
    }
 
    public void AttachToWebView(IpcSender ipcSender)
    {
        _ipcSender = ipcSender;
    }
 
    public JsonSerializerOptions ReadJsonSerializerOptions() => JsonSerializerOptions;
 
    protected override void BeginInvokeJS(long taskId, string identifier, string argsJson, JSCallResultType resultType, long targetInstanceId)
    {
        var invocationInfo = new JSInvocationInfo
        {
            AsyncHandle = taskId,
            Identifier = identifier,
            ArgsJson = argsJson,
            CallType = JSCallType.FunctionCall,
            ResultType = resultType,
            TargetInstanceId = targetInstanceId,
        };
 
        BeginInvokeJS(invocationInfo);
    }
 
    internal void MarkAsDisconnected()
    {
        _disconnected = true;
    }
 
    protected override void BeginInvokeJS(in JSInvocationInfo invocationInfo)
    {
        if (_disconnected)
        {
            throw new JSDisconnectedException(
                "JavaScript interop calls cannot be issued at this time. This is because the WebView has been disposed " +
                "or the page has navigated away.");
        }
 
        if (_ipcSender is null)
        {
            throw new InvalidOperationException("Cannot invoke JavaScript outside of a WebView context.");
        }
 
        _ipcSender.BeginInvokeJS(invocationInfo);
    }
 
    protected override void EndInvokeDotNet(DotNetInvocationInfo invocationInfo, in DotNetInvocationResult invocationResult)
    {
        var resultJsonOrErrorMessage = invocationResult.Success
            ? invocationResult.ResultJson
            : invocationResult.Exception.ToString();
        _ipcSender.EndInvokeDotNet(invocationInfo.CallId, invocationResult.Success, resultJsonOrErrorMessage);
    }
 
    protected override void SendByteArray(int id, byte[] data)
    {
        _ipcSender.SendByteArray(id, data);
    }
 
    protected override Task<Stream> ReadJSDataAsStreamAsync(IJSStreamReference jsStreamReference, long totalLength, CancellationToken cancellationToken = default)
        => Task.FromResult<Stream>(PullFromJSDataStream.CreateJSDataStream(this, jsStreamReference, totalLength, cancellationToken));
 
    protected override Task TransmitStreamAsync(long streamId, DotNetStreamReference dotNetStreamReference)
    {
        return TransmitDataStreamToJS.TransmitStreamAsync(this, "Blazor._internal.receiveWebViewDotNetDataStream", streamId, dotNetStreamReference);
    }
}