package com.atlassian.webdriver.testing.rule;
   
   import com.atlassian.webdriver.AtlassianWebDriver;
   import com.atlassian.webdriver.browsers.WebDriverBrowserAutoInstall;
   import com.google.common.base.Supplier;
   import com.google.common.base.Suppliers;
   import org.openqa.selenium.WebDriver;
   
   import javax.annotation.Nonnull;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  /**
   * <p/>
   * Support for rules that need a {@link org.openqa.selenium.WebDriver} instance.
   *
   * <p/>
   * This class defines 'templates' for constructors to provide the WebDriver instance in a generic way. By default it
   * falls back to {@link com.atlassian.webdriver.LifecycleAwareWebDriverGrid}.
   *
   * @since 2.1
   */
  public final class WebDriverSupport<WD extends WebDriver>
  {
      public static WebDriverSupport<AtlassianWebDriver> fromAutoInstall()
      {
          return new WebDriverSupport<AtlassianWebDriver>(WebDriverBrowserAutoInstall.driverSupplier());
      }
  
      public static <VE extends WebDriver> WebDriverSupport<VE> forSupplier(Supplier<? extends VE> driverSupplier)
      {
          return new WebDriverSupport<VE>(driverSupplier);
      }
  
      public static <VE extends WebDriver> WebDriverSupport<VE> forInstance(VE webDriver)
      {
          return new WebDriverSupport<VE>(Suppliers.ofInstance(checkNotNull(webDriver, "webDriver")));
      }
  
      private final Supplier<? extends WD> driverSupplier;
  
      private WebDriverSupport(@Nonnull Supplier<? extends WD> driverSupplier)
      {
          this.driverSupplier = Suppliers.memoize(checkNotNull(driverSupplier, "driverSupplier"));
      }
  
      @Nonnull
      public final WD getDriver()
      {
          return driverSupplier.get();
      }
  
  }