From 045e58778ad6ec30c5ec8f565f32bda0ac759e5f Mon Sep 17 00:00:00 2001
From: "Lea\\Anthony" <lea.anthony@gmail.com>
Date: Mon, 27 Dec 2021 18:09:41 +1100
Subject: [PATCH] Actually commit webview2runtime

---
 .../webview2runtime/webview2runtime.go        | 168 ++++++++++++++++++
 1 file changed, 168 insertions(+)
 create mode 100644 v2/internal/webview2runtime/webview2runtime.go

diff --git a/v2/internal/webview2runtime/webview2runtime.go b/v2/internal/webview2runtime/webview2runtime.go
new file mode 100644
index 00000000..27a17fb7
--- /dev/null
+++ b/v2/internal/webview2runtime/webview2runtime.go
@@ -0,0 +1,168 @@
+//go:build windows
+// +build windows
+
+package webview2runtime
+
+import (
+	_ "embed"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"syscall"
+	"unsafe"
+)
+
+//go:embed MicrosoftEdgeWebview2Setup.exe
+var setupexe []byte
+
+// Info contains all the information about an installation of the webview2 runtime.
+type Info struct {
+	Location        string
+	Name            string
+	Version         string
+	SilentUninstall string
+}
+
+// IsOlderThan returns true if the installed version is older than the given required version.
+// Returns error if something goes wrong.
+func (i *Info) IsOlderThan(requiredVersion string) (bool, error) {
+	var mod = syscall.NewLazyDLL("WebView2Loader.dll")
+	var CompareBrowserVersions = mod.NewProc("CompareBrowserVersions")
+	v1, err := syscall.UTF16PtrFromString(i.Version)
+	if err != nil {
+		return false, err
+	}
+	v2, err := syscall.UTF16PtrFromString(requiredVersion)
+	if err != nil {
+		return false, err
+	}
+	var result int = 9
+	_, _, err = CompareBrowserVersions.Call(uintptr(unsafe.Pointer(v1)), uintptr(unsafe.Pointer(v2)), uintptr(unsafe.Pointer(&result)))
+	if result < -1 || result > 1 {
+		return false, err
+	}
+	return result == -1, nil
+}
+
+func downloadBootstrapper() (string, error) {
+	bootstrapperURL := `https://go.microsoft.com/fwlink/p/?LinkId=2124703`
+	installer := filepath.Join(os.TempDir(), `MicrosoftEdgeWebview2Setup.exe`)
+
+	// Download installer
+	out, err := os.Create(installer)
+	defer out.Close()
+	if err != nil {
+		return "", err
+	}
+	resp, err := http.Get(bootstrapperURL)
+	defer resp.Body.Close()
+	if err != nil {
+		err = out.Close()
+		return "", err
+	}
+	_, err = io.Copy(out, resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	return installer, nil
+}
+
+// InstallUsingEmbeddedBootstrapper will download the bootstrapper from Microsoft and run it to install
+// the latest version of the runtime.
+// Returns true if the installer ran successfully.
+// Returns an error if something goes wrong
+func InstallUsingEmbeddedBootstrapper() (bool, error) {
+
+	installer := filepath.Join(os.TempDir(), `MicrosoftEdgeWebview2Setup.exe`)
+	err := os.WriteFile(installer, setupexe, 0755)
+	if err != nil {
+		return false, err
+	}
+	result, err := runInstaller(installer)
+	if err != nil {
+		return false, err
+	}
+
+	return result, os.Remove(installer)
+
+}
+
+// InstallUsingBootstrapper will extract the embedded bootstrapper from Microsoft and run it to install
+// the latest version of the runtime.
+// Returns true if the installer ran successfully.
+// Returns an error if something goes wrong
+func InstallUsingBootstrapper() (bool, error) {
+
+	installer, err := downloadBootstrapper()
+	if err != nil {
+		return false, err
+	}
+
+	result, err := runInstaller(installer)
+	if err != nil {
+		return false, err
+	}
+
+	return result, os.Remove(installer)
+
+}
+
+func runInstaller(installer string) (bool, error) {
+	err := ShellExecuteAndWait(0, "runas", installer, "", os.Getenv("TMP"), syscall.SW_NORMAL)
+	if err != nil {
+		fmt.Println(err)
+		return false, err
+	}
+	return true, nil
+}
+
+// Confirm will prompt the user with a message and OK / CANCEL buttons.
+// Returns true if OK is selected by the user.
+// Returns an error if something went wrong.
+func Confirm(caption string, title string) (bool, error) {
+	var flags uint = 0x00000001 // MB_OKCANCEL
+	result, err := MessageBox(caption, title, flags)
+	if err != nil {
+		return false, err
+	}
+	return result == 1, nil
+}
+
+// Error will an error message to the user.
+// Returns an error if something went wrong.
+func Error(caption string, title string) error {
+	var flags uint = 0x00000010 // MB_ICONERROR
+	_, err := MessageBox(caption, title, flags)
+	return err
+}
+
+// MessageBox prompts the user with the given caption and title.
+// Flags may be provided to customise the dialog.
+// Returns an error if something went wrong.
+func MessageBox(caption string, title string, flags uint) (int, error) {
+	captionUTF16, err := syscall.UTF16PtrFromString(caption)
+	if err != nil {
+		return -1, err
+	}
+	titleUTF16, err := syscall.UTF16PtrFromString(title)
+	if err != nil {
+		return -1, err
+	}
+	ret, _, _ := syscall.NewLazyDLL("user32.dll").NewProc("MessageBoxW").Call(
+		uintptr(0),
+		uintptr(unsafe.Pointer(captionUTF16)),
+		uintptr(unsafe.Pointer(titleUTF16)),
+		uintptr(flags))
+
+	return int(ret), nil
+}
+
+// OpenInstallerDownloadWebpage will open the browser on the WebView2 download page
+func OpenInstallerDownloadWebpage() error {
+	cmd := exec.Command("rundll32", "url.dll,FileProtocolHandler", "https://developer.microsoft.com/en-us/microsoft-edge/webview2/")
+	return cmd.Run()
+}