tauri_plugin_prevent_default/

lib.rs

#![cfg_attr(docsrs, feature(doc_auto_cfg))]
#![doc = include_str!("../README.md")]
#![allow(clippy::format_push_string)]

mod display;
mod error;
mod shortcut;

#[cfg(all(target_os = "windows", feature = "unstable-windows"))]
mod platform;

use bitflags::bitflags;
use std::sync::Arc;
use tauri::plugin::{Builder as PluginBuilder, TauriPlugin};
use tauri::{Manager, Runtime};

pub use error::Error;
pub use shortcut::{
  KeyboardShortcut, KeyboardShortcutBuilder, ModifierKey, PointerEvent, PointerShortcut,
  PointerShortcutBuilder, Shortcut, ShortcutKind,
};

#[cfg(all(target_os = "windows", feature = "unstable-windows"))]
pub use platform::windows::PlatformOptions;

bitflags! {
  #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
  pub struct Flags: u32 {
      /// Find (`Ctrl+F`, `Ctrl+G`, `Ctrl+Shift+G`, `F3`)
      const FIND            = 1 << 0;
      /// Caret browsing (`F7`)
      const CARET_BROWSING  = 1 << 1;
      /// Developer tools (`Ctrl+Shift+I`)
      const DEV_TOOLS       = 1 << 2;
      /// Downloads (`Ctrl+J`)
      const DOWNLOADS       = 1 << 3;
      /// Focus move (`Shift+Tab`)
      const FOCUS_MOVE      = 1 << 4;
      /// Reload (`F5`, `Ctrl+F5`, `Shift+F5`, `Ctrl+R`, `Ctrl+Shift+R`)
      const RELOAD          = 1 << 5;
      /// Source (`Ctrl+U`)
      const SOURCE          = 1 << 6;
      /// Open (`Ctrl+O`)
      const OPEN            = 1 << 7;
      /// Print document (`Ctrl+P`, `Ctrl+Shift+P`)
      const PRINT           = 1 << 8;
      /// Context menu (mouse right click)
      const CONTEXT_MENU    = 1 << 9;
  }
}

impl Flags {
  /// All keyboard shortcuts.
  pub fn keyboard() -> Self {
    Self::all().difference(Self::pointer())
  }

  /// All pointer shortcuts.
  pub fn pointer() -> Self {
    Self::CONTEXT_MENU
  }

  /// Keep `CONTEXT_MENU`, `DEV_TOOLS`, and `RELOAD` shortcuts enabled when in debug mode.
  pub fn debug() -> Self {
    if cfg!(debug_assertions) {
      Self::all().difference(Self::CONTEXT_MENU | Self::DEV_TOOLS | Self::RELOAD)
    } else {
      Self::all()
    }
  }
}

impl Default for Flags {
  fn default() -> Self {
    Self::all()
  }
}

pub struct Builder {
  flags: Flags,
  shortcuts: Vec<Box<dyn Shortcut>>,
  check_origin: Option<String>,

  #[cfg(all(target_os = "windows", feature = "unstable-windows"))]
  platform: PlatformOptions,
}

#[allow(clippy::derivable_impls)]
impl Default for Builder {
  fn default() -> Self {
    Self {
      flags: Flags::default(),
      shortcuts: Vec::new(),
      check_origin: None,

      #[cfg(all(target_os = "windows", feature = "unstable-windows"))]
      platform: PlatformOptions::default(),
    }
  }
}

impl Builder {
  /// Create a new builder with default values.
  pub fn new() -> Self {
    Self::default()
  }

  /// Set flags to control which shortcuts the plugin should disable.
  ///
  /// # Examples
  /// ```
  /// use tauri_plugin_prevent_default::Flags;
  ///
  /// tauri_plugin_prevent_default::Builder::new()
  ///   .with_flags(Flags::CONTEXT_MENU | Flags::PRINT | Flags::DOWNLOADS)
  ///   .build();
  /// ```
  #[must_use]
  pub fn with_flags(mut self, flags: Flags) -> Self {
    self.flags = flags;
    self
  }

  /// Disable a custom shortcut.
  ///
  /// # Examples
  /// ```
  /// use tauri_plugin_prevent_default::KeyboardShortcut;
  /// use tauri_plugin_prevent_default::ModifierKey::{CtrlKey, ShiftKey};
  ///
  /// tauri_plugin_prevent_default::Builder::new()
  ///   .shortcut(KeyboardShortcut::new("F12"))
  ///   .shortcut(KeyboardShortcut::with_modifiers("E", &[CtrlKey, ShiftKey]))
  ///   .shortcut(KeyboardShortcut::with_shift_alt("I"))
  ///   .build();
  /// ```
  #[must_use]
  pub fn shortcut<S>(mut self, shortcut: S) -> Self
  where
    S: Shortcut + 'static,
  {
    self.shortcuts.push(Box::new(shortcut));
    self
  }

  /// Check location origin before disabling the shortcuts.
  #[must_use]
  pub fn check_origin(mut self, origin: impl AsRef<str>) -> Self {
    self.check_origin = origin.as_ref().to_owned().into();
    self
  }

  /// Windows-specific options.
  #[must_use]
  #[cfg(all(target_os = "windows", feature = "unstable-windows"))]
  pub fn platform(mut self, options: PlatformOptions) -> Self {
    self.platform = options;
    self
  }

  /// Build the plugin.
  pub fn build<R: Runtime>(mut self) -> TauriPlugin<R> {
    let script = self.create_script();
    self
      .plugin_builder()
      .js_init_script(script.into())
      .build()
  }

  /// Build the plugin, but do not inject the script into the webviews.
  /// The script should then be manually set as the initialization script when creating the window.
  ///
  /// # Examples
  /// ```
  /// use tauri::{AppHandle, WebviewUrl, WebviewWindowBuilder};
  /// use tauri_plugin_prevent_default::PreventDefault;
  ///
  /// fn create_window(app: &AppHandle) {
  ///   let url = WebviewUrl::App("index.html".into());
  ///   WebviewWindowBuilder::new(app, "main", url)
  ///     .initialization_script(app.script())
  ///     .build()
  ///     .unwrap();
  /// }
  /// ```
  pub fn build_with_manual_injection<R: Runtime>(mut self) -> TauriPlugin<R> {
    let script = self.create_script();
    self
      .plugin_builder()
      .setup(move |app, _| {
        app.manage(script);
        Ok(())
      })
      .build()
  }

  #[allow(clippy::unused_self)]
  fn plugin_builder<R: Runtime>(self) -> PluginBuilder<R> {
    #[allow(unused_mut)]
    let mut builder = PluginBuilder::new("prevent-default");

    #[cfg(all(target_os = "windows", feature = "unstable-windows"))]
    {
      let options = self.platform;
      builder = builder.on_webview_ready(move |webview| {
        platform::windows::on_webview_ready(&webview, &options);
      });
    }

    builder
  }

  fn create_script(&mut self) -> Script {
    self.add_keyboard_shortcuts();
    self.add_pointer_shortcuts();

    let mut script = String::new();

    for shortcut in &mut self.shortcuts {
      match shortcut.kind() {
        ShortcutKind::Keyboard(it) => {
          let modifiers = it.modifiers();
          let mut options = String::with_capacity(modifiers.len() * 12);
          for modifier in modifiers {
            options.push_str(&format!("{modifier}:true,"));
          }

          let options = options.trim_end_matches(',');
          script.push_str(&format!("onKey('{}',{{{}}});", it.key(), options));
        }
        ShortcutKind::Pointer(it) => {
          script.push_str(&format!("onPointer('{}');", it.event()));
        }
      }
    }

    let origin = self
      .check_origin
      .as_deref()
      .map(|it| format!("const ORIGIN='{it}';"))
      .unwrap_or_else(|| "const ORIGIN=null;".to_owned());

    include_str!("../scripts/script.js")
      .trim()
      .replace("/*ORIGIN*/", &origin)
      .replace("/*SCRIPT*/", &script)
      .into()
  }

  fn add_keyboard_shortcuts(&mut self) {
    use shortcut::ModifierKey::{CtrlKey, ShiftKey};

    macro_rules! on_key {
      ($($arg:literal)+) => {
        $(
          let shortcut = KeyboardShortcut::new($arg);
          self.shortcuts.push(Box::new(shortcut));
        )*
      };
      ($modifiers:expr, $($arg:literal),+) => {
        $(
          let shortcut = KeyboardShortcut::with_modifiers($arg, $modifiers);
          self.shortcuts.push(Box::new(shortcut));
        )*
      };
    }

    if self.flags.contains(Flags::FIND) {
      on_key!("F3");
      on_key!(&[CtrlKey], "f", "g");
      on_key!(&[CtrlKey, ShiftKey], "g");
    }

    if self.flags.contains(Flags::CARET_BROWSING) {
      on_key!("F7");
    }

    if self.flags.contains(Flags::DEV_TOOLS) {
      on_key!(&[CtrlKey, ShiftKey], "i");
    }

    if self.flags.contains(Flags::DOWNLOADS) {
      on_key!(&[CtrlKey], "j");
    }

    if self.flags.contains(Flags::FOCUS_MOVE) {
      on_key!(&[ShiftKey], "Tab");
    }

    if self.flags.contains(Flags::RELOAD) {
      on_key!("F5");
      on_key!(&[CtrlKey], "F5");
      on_key!(&[ShiftKey], "F5");
      on_key!(&[CtrlKey], "r");
      on_key!(&[CtrlKey, ShiftKey], "r");
    }

    if self.flags.contains(Flags::SOURCE) {
      on_key!(&[CtrlKey], "u");
    }

    if self.flags.contains(Flags::OPEN) {
      on_key!(&[CtrlKey], "o");
    }

    if self.flags.contains(Flags::PRINT) {
      on_key!(&[CtrlKey], "p");
      on_key!(&[CtrlKey, ShiftKey], "p");
    }
  }

  fn add_pointer_shortcuts(&mut self) {
    if self.flags.contains(Flags::CONTEXT_MENU) {
      let shortcut = PointerShortcut::new(PointerEvent::ContextMenu);
      self.shortcuts.push(Box::new(shortcut));
    }
  }
}

/// Provide access to the script.
pub trait PreventDefault<R: Runtime> {
  /// Retrieve the script.
  ///
  /// # Panics
  ///
  /// Panics if the plugin was not [built with manual injection](Builder::build_with_manual_injection).
  fn script(&self) -> Script;

  /// Attempt to retrieve the script.
  ///
  /// Returns `Some` if the plugin was [built with manual injection](Builder::build_with_manual_injection).
  /// Otherwise returns `None`.
  fn try_script(&self) -> Option<Script>;
}

impl<R, T> PreventDefault<R> for T
where
  R: Runtime,
  T: Manager<R>,
{
  fn script(&self) -> Script {
    (*self.app_handle().state::<Script>()).clone()
  }

  fn try_script(&self) -> Option<Script> {
    self
      .app_handle()
      .try_state::<Script>()
      .as_deref()
      .cloned()
  }
}

/// Script to be injected into the webview.
pub struct Script(Arc<str>);

impl Clone for Script {
  fn clone(&self) -> Self {
    Self(Arc::clone(&self.0))
  }
}

impl From<String> for Script {
  fn from(value: String) -> Self {
    Script(Arc::from(value))
  }
}

impl From<Script> for String {
  fn from(value: Script) -> Self {
    String::from(value.0.as_ref())
  }
}

/// Initialize the plugin with default values.
pub fn init<R: Runtime>() -> TauriPlugin<R> {
  Builder::default().build()
}

/// Initialize the plugin with default values while also allowing for manual injection.
pub fn init_with_manual_injection<R: Runtime>() -> TauriPlugin<R> {
  Builder::default().build_with_manual_injection()
}

/// Initialize the plugin with given flags.
pub fn with_flags<R: Runtime>(flags: Flags) -> TauriPlugin<R> {
  Builder::new().with_flags(flags).build()
}

/// Initialize the plugin with given flags while also allowing for manual injection.
pub fn with_flags_and_manual_injection<R: Runtime>(flags: Flags) -> TauriPlugin<R> {
  Builder::new()
    .with_flags(flags)
    .build_with_manual_injection()
}

/// Initialize the plugin with the default [debug flags](Flags::debug).
pub fn debug<R: Runtime>() -> TauriPlugin<R> {
  Builder::new().with_flags(Flags::debug()).build()
}

/// Initialize the plugin with the default [debug flags](Flags::debug)
/// while also allowing for manual injection.
pub fn debug_with_manual_injection<R: Runtime>() -> TauriPlugin<R> {
  Builder::new()
    .with_flags(Flags::debug())
    .build_with_manual_injection()
}