AvaloniaStack/Avalonia-PC/Views/MainWindow.axaml.cs
2026-04-23 16:23:40 +08:00

595 lines
20 KiB
C#

using Avalonia.Controls;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Reflection;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
namespace Avalonia_PC.Views
{
public partial class MainWindow : Window
{
private const string AppScheme = "app";
private const string? OnlineStartupUrl = null;
private const string? LocalStartupPath = null;
private static readonly JsonSerializerOptions BridgeJsonSerializerOptions = new()
{
PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
};
private NativeWebView? _webView;
private bool _eventsAttached;
private object? _webViewAdapter;
private HttpListener? _localHttpServer;
private CancellationTokenSource? _localHttpServerCts;
private string? _localHttpBaseUrl;
private string? _localHttpRoot;
public MainWindow()
{
InitializeComponent();
Opened += OnOpened;
Closed += OnClosed;
}
private async void OnOpened(object? sender, EventArgs e)
{
if (_eventsAttached)
{
return;
}
_webView = this.FindControl<NativeWebView>("WebView");
if (_webView is null)
{
return;
}
_eventsAttached = true;
_webView.NavigationCompleted += OnNavigationCompleted;
_webView.WebMessageReceived += OnWebMessageReceived;
_webView.AdapterCreated += OnAdapterCreated;
await LoadInitialContentAsync();
}
private void OnAdapterCreated(object? sender, WebViewAdapterEventArgs e)
{
_webViewAdapter = e.GetType().GetProperty("Adapter")?.GetValue(e);
}
private void OnClosed(object? sender, EventArgs e)
{
if (_webView is not null)
{
_webView.NavigationCompleted -= OnNavigationCompleted;
_webView.WebMessageReceived -= OnWebMessageReceived;
_webView.AdapterCreated -= OnAdapterCreated;
}
_webViewAdapter = null;
StopLocalHttpServer();
}
private async void OnNavigationCompleted(object? sender, WebViewNavigationCompletedEventArgs e)
{
await InjectBridgeScriptAsync();
}
private async void OnWebMessageReceived(object? sender, WebMessageReceivedEventArgs e)
{
var messageJson = e.Body;
if (string.IsNullOrWhiteSpace(messageJson))
{
return;
}
AppResponse? response = null;
try
{
using var document = JsonDocument.Parse(messageJson);
var root = document.RootElement;
if (!root.TryGetProperty("kind", out var kindProperty))
{
return;
}
var kind = kindProperty.GetString();
if (string.Equals(kind, "app-open-devtools", StringComparison.OrdinalIgnoreCase))
{
TryOpenDevTools();
return;
}
if (!string.Equals(kind, "app-request", StringComparison.OrdinalIgnoreCase))
{
return;
}
response = await HandleAppRequestAsync(root);
}
catch (Exception ex)
{
response = new AppResponse
{
Kind = "app-response",
Id = TryGetRequestId(messageJson),
StatusCode = 500,
StatusMessage = "Internal Server Error",
Body = JsonSerializer.Serialize(new { success = false, error = ex.Message }),
Headers = CreateJsonHeaders(),
};
}
if (_webView is not null && response is not null)
{
var responseJson = JsonSerializer.Serialize(response, BridgeJsonSerializerOptions);
var responseJsonLiteral = JsonSerializer.Serialize(responseJson);
await _webView.InvokeScript($"window.__dispatchAppResponse({responseJsonLiteral})");
}
}
private async Task LoadInitialContentAsync()
{
if (_webView is null)
{
return;
}
var onlineUrl = GetConfiguredOnlineStartupUrl();
if (onlineUrl is not null)
{
StopLocalHttpServer();
_webView.Source = onlineUrl;
return;
}
var localHtmlPath = GetConfiguredLocalStartupPath();
if (string.IsNullOrWhiteSpace(localHtmlPath) || !File.Exists(localHtmlPath))
{
return;
}
var localRoot = Path.GetDirectoryName(localHtmlPath);
if (string.IsNullOrWhiteSpace(localRoot))
{
return;
}
await EnsureLocalHttpServerStartedAsync(localRoot);
if (string.IsNullOrWhiteSpace(_localHttpBaseUrl))
{
_webView.Source = new Uri(localHtmlPath);
return;
}
_webView.Source = new Uri(new Uri(_localHttpBaseUrl), Path.GetFileName(localHtmlPath));
}
private async Task InjectBridgeScriptAsync()
{
if (_webView is null)
{
return;
}
const string script = """
if (!window.__appBridgeInstalled) {
window.__appBridgeInstalled = true;
window.isWebView2 = true;
const pending = new Map();
const tryOpenDevTools = () => {
window.invokeCSharpAction(JSON.stringify({ kind: 'app-open-devtools' }));
};
window.__dispatchAppResponse = function(jsonStr) {
const payload = JSON.parse(jsonStr);
const responseId = payload.id ?? payload.Id;
const entry = pending.get(responseId);
if (!entry) return;
pending.delete(responseId);
entry.resolve(new Response(payload.body ?? payload.Body ?? '', {
status: payload.statusCode ?? payload.StatusCode ?? 200,
statusText: payload.statusMessage ?? payload.StatusMessage ?? 'OK',
headers: payload.headers ?? payload.Headers ?? { 'Content-Type': 'application/json' }
}));
};
const nativeFetch = window.fetch ? window.fetch.bind(window) : null;
document.addEventListener('keydown', event => {
if (event.key === 'F12' || (event.ctrlKey && event.shiftKey && (event.key === 'I' || event.key === 'i'))) {
event.preventDefault();
tryOpenDevTools();
}
}, true);
document.addEventListener('contextmenu', event => {
if (event.shiftKey) {
event.preventDefault();
tryOpenDevTools();
}
}, true);
window.fetch = async (input, init) => {
const request = input instanceof Request ? input : null;
const requestUrl = typeof input === 'string' || input instanceof URL
? input.toString()
: request?.url;
if (!requestUrl || !requestUrl.startsWith('app://')) {
if (!nativeFetch) throw new Error('window.fetch is not available.');
return nativeFetch(input, init);
}
const combinedHeaders = new Headers(request?.headers);
if (init?.headers) {
new Headers(init.headers).forEach((value, key) => combinedHeaders.set(key, value));
}
const headers = {};
combinedHeaders.forEach((value, key) => headers[key] = value);
let body = init?.body;
if (body === undefined && request) {
body = await request.clone().text();
}
if (body && typeof body !== 'string') {
body = await new Response(body).text();
}
const id = globalThis.crypto?.randomUUID?.() ?? `${Date.now()}-${Math.random()}`;
const responsePromise = new Promise((resolve, reject) => {
const timeoutId = setTimeout(() => {
pending.delete(id);
reject(new Error(`Timed out waiting for ${requestUrl}`));
}, 30000);
pending.set(id, {
resolve: response => { clearTimeout(timeoutId); resolve(response); },
reject: error => { clearTimeout(timeoutId); reject(error); }
});
});
window.invokeCSharpAction(JSON.stringify({
kind: 'app-request',
id,
url: requestUrl,
method: init?.method ?? request?.method ?? 'GET',
headers,
body: body ?? null
}));
return responsePromise;
};
}
""";
await _webView.InvokeScript(script);
}
private async Task<AppResponse> HandleAppRequestAsync(JsonElement request)
{
var id = request.TryGetProperty("id", out var idProperty) ? idProperty.GetString() : null;
var url = request.TryGetProperty("url", out var urlProperty) ? urlProperty.GetString() : null;
var method = request.TryGetProperty("method", out var methodProperty) ? methodProperty.GetString() : "GET";
var body = request.TryGetProperty("body", out var bodyProperty) ? bodyProperty.GetString() : null;
var headers = ExtractHeaders(request);
return await HandleAppRequestAsync(id, url, method, body, headers);
}
private async Task<AppResponse> HandleAppRequestAsync(
string? id,
string? rawUrl,
string? method,
string? body,
Dictionary<string, string> headers)
{
var response = new AppResponse
{
Kind = "app-response",
Id = id,
StatusCode = 200,
StatusMessage = "OK",
Headers = CreateJsonHeaders(),
};
try
{
var uri = new Uri(rawUrl ?? throw new InvalidOperationException("请求地址不能为空。"));
var path = uri.AbsolutePath.TrimStart('/');
var normalizedPath = path.StartsWith("api/", StringComparison.OrdinalIgnoreCase)
? path
: $"api/{path}";
var authorization = GetAuthorizationHeader(headers);
_ = authorization;
if (string.Equals(method, "OPTIONS", StringComparison.OrdinalIgnoreCase))
{
response.StatusCode = 200;
response.StatusMessage = "OK";
response.Body = JsonSerializer.Serialize(new { success = true });
return response;
}
if (string.Equals(normalizedPath, "api/getUser", StringComparison.OrdinalIgnoreCase))
{
var user = await GetUserFromDatabaseAsync();
response.Body = JsonSerializer.Serialize(new { success = true, data = user });
return response;
}
if (string.Equals(normalizedPath, "api/processData", StringComparison.OrdinalIgnoreCase))
{
var input = string.Empty;
if (!string.IsNullOrWhiteSpace(body))
{
using var jsonDocument = JsonDocument.Parse(body);
if (jsonDocument.RootElement.TryGetProperty("input", out var inputProperty))
{
input = inputProperty.GetString() ?? string.Empty;
}
}
var result = await ProcessDataAsync(input);
response.Body = JsonSerializer.Serialize(new { success = true, result });
return response;
}
response.StatusCode = 404;
response.StatusMessage = "Not Found";
response.Body = JsonSerializer.Serialize(new { success = false, error = "API not found" });
return response;
}
catch (Exception ex)
{
response.StatusCode = 500;
response.StatusMessage = "Internal Server Error";
response.Body = JsonSerializer.Serialize(new { success = false, error = ex.Message });
return response;
}
}
private static Dictionary<string, string> CreateJsonHeaders() => new()
{
["Content-Type"] = "application/json; charset=utf-8",
["Access-Control-Allow-Origin"] = "*",
["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS",
["Access-Control-Allow-Headers"] = "Content-Type, Authorization",
};
private static Dictionary<string, string> ExtractHeaders(JsonElement request)
{
if (!request.TryGetProperty("headers", out var headersElement) ||
headersElement.ValueKind != JsonValueKind.Object)
{
return new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
}
var headers = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
foreach (var property in headersElement.EnumerateObject())
{
headers[property.Name] = property.Value.GetString() ?? string.Empty;
}
return headers;
}
private static string? GetAuthorizationHeader(Dictionary<string, string> headers)
{
return headers.FirstOrDefault(
entry => string.Equals(entry.Key, "Authorization", StringComparison.OrdinalIgnoreCase)).Value;
}
private static string? TryGetRequestId(string messageJson)
{
try
{
using var document = JsonDocument.Parse(messageJson);
return document.RootElement.TryGetProperty("id", out var idProperty) ? idProperty.GetString() : null;
}
catch
{
return null;
}
}
private static Uri? GetConfiguredOnlineStartupUrl()
{
if (string.IsNullOrWhiteSpace(OnlineStartupUrl))
{
return null;
}
if (!Uri.TryCreate(OnlineStartupUrl, UriKind.Absolute, out var uri))
{
return null;
}
return uri.Scheme is "http" or "https" ? uri : null;
}
private static string? GetConfiguredLocalStartupPath()
{
if (!string.IsNullOrWhiteSpace(LocalStartupPath))
{
return Path.GetFullPath(LocalStartupPath);
}
return Path.Combine(AppContext.BaseDirectory, "www", "index.html");
}
private async Task EnsureLocalHttpServerStartedAsync(string localRoot)
{
if (!string.IsNullOrWhiteSpace(_localHttpBaseUrl) &&
_localHttpServer is not null &&
string.Equals(_localHttpRoot, localRoot, StringComparison.OrdinalIgnoreCase))
{
return;
}
StopLocalHttpServer();
var port = GetAvailableTcpPort();
var prefix = $"http://127.0.0.1:{port}/";
_localHttpServerCts = new CancellationTokenSource();
_localHttpServer = new HttpListener();
_localHttpServer.Prefixes.Add(prefix);
_localHttpServer.Start();
_localHttpBaseUrl = prefix;
_localHttpRoot = localRoot;
_ = Task.Run(() => RunLocalHttpServerLoopAsync(_localHttpServer, _localHttpServerCts.Token, localRoot));
}
private static async Task RunLocalHttpServerLoopAsync(HttpListener listener, CancellationToken cancellationToken, string wwwRoot)
{
try
{
while (!cancellationToken.IsCancellationRequested)
{
var context = await listener.GetContextAsync();
_ = Task.Run(() => HandleLocalHttpRequest(context, wwwRoot), cancellationToken);
}
}
catch
{
}
}
private static async Task HandleLocalHttpRequest(HttpListenerContext context, string wwwRoot)
{
try
{
var relativePath = context.Request.Url?.AbsolutePath.TrimStart('/') ?? string.Empty;
if (string.IsNullOrWhiteSpace(relativePath))
{
relativePath = "index.html";
}
relativePath = relativePath.Replace('/', Path.DirectorySeparatorChar);
var fullPath = Path.GetFullPath(Path.Combine(wwwRoot, relativePath));
var fullRoot = Path.GetFullPath(wwwRoot);
if (!fullPath.StartsWith(fullRoot, StringComparison.OrdinalIgnoreCase) || !File.Exists(fullPath))
{
context.Response.StatusCode = 404;
context.Response.Close();
return;
}
context.Response.ContentType = GetContentType(fullPath);
await using var input = File.OpenRead(fullPath);
context.Response.ContentLength64 = input.Length;
await input.CopyToAsync(context.Response.OutputStream);
context.Response.OutputStream.Close();
}
catch
{
try
{
context.Response.StatusCode = 500;
context.Response.Close();
}
catch
{
}
}
}
private static string GetContentType(string filePath)
{
return Path.GetExtension(filePath).ToLowerInvariant() switch
{
".html" => "text/html; charset=utf-8",
".js" => "application/javascript; charset=utf-8",
".css" => "text/css; charset=utf-8",
".json" => "application/json; charset=utf-8",
_ => "application/octet-stream",
};
}
private static int GetAvailableTcpPort()
{
var listener = new TcpListener(IPAddress.Loopback, 0);
listener.Start();
var port = ((IPEndPoint)listener.LocalEndpoint).Port;
listener.Stop();
return port;
}
private void TryOpenDevTools()
{
if (_webViewAdapter is null)
{
return;
}
var adapterType = _webViewAdapter.GetType();
var method = adapterType.GetMethod("OpenDevTools", BindingFlags.Public | BindingFlags.Instance) ??
adapterType.GetMethod("ShowDevTools", BindingFlags.Public | BindingFlags.Instance);
method?.Invoke(_webViewAdapter, null);
}
private void StopLocalHttpServer()
{
try
{
_localHttpServerCts?.Cancel();
_localHttpServer?.Stop();
_localHttpServer?.Close();
}
catch
{
}
finally
{
_localHttpServerCts?.Dispose();
_localHttpServerCts = null;
_localHttpServer = null;
_localHttpBaseUrl = null;
_localHttpRoot = null;
}
}
private static async Task<object> GetUserFromDatabaseAsync()
{
await Task.Delay(100);
return new { id = 1, name = "张三", email = "zhangsan@example.com" };
}
private static async Task<string> ProcessDataAsync(string? input)
{
await Task.Delay(200);
return $"Processed: {input?.ToUpperInvariant()}";
}
private sealed class AppResponse
{
public string Kind { get; set; } = string.Empty;
public string? Id { get; set; }
public int StatusCode { get; set; }
public string StatusMessage { get; set; } = string.Empty;
public string Body { get; set; } = string.Empty;
public Dictionary<string, string> Headers { get; set; } = new();
}
}
}