import * as cp from "child_process";

async function checkPijulInstallation (config: vscode.WorkspaceConfiguration, outputChannel: vscode.OutputChannel) {
  let path = config.get<string>("installationPath");
  if (!path) {
    // We need a path to proceed, ask the user to select one or stop activation
    if (!config.get<boolean>("ignoreMissingInstallation")) {
      const selectInstallation = "Select a Pijul Executable";
      const ignore = "Don't Show this Warning Again";
      const choice = await vscode.window.showWarningMessage(
        "No Pijul installation has been configured for use with the extension. Select one to enable Pijul integration",
        selectInstallation,
        ignore
      );
      if (choice === selectInstallation) {
        let fileFilters: { [name: string]: string[] } | undefined;
        if (process.platform === "win32") {
          fileFilters = {
            svn: ["exe", "bat"]
          };
        }
        // Ask the user to select an executable location
        const pijulInstallation = await vscode.window.showOpenDialog({
          canSelectFiles: true,
          canSelectFolders: false,
          canSelectMany: false,
          filters: fileFilters
        });
        if (pijulInstallation && pijulInstallation[0]) {
          const exePath = pijulInstallation[0].fsPath;
          await config.update("installationPath", exePath);
          path = exePath;
          outputChannel.appendLine("Updated extension configuration to use Pijul installation at " + exePath);
        } else {
          // Not sure if this case is possible, this is here for safety
          return;
        }
      } else {
        config.update("ignoreMissingInstallation", true);
        return;
      }
    } else {
      // TODO: Wait for change to the configuration
      return;
    }
  }
  const child = cp.spawn(path, ["--version"]);
  child.stdout.on("data", (b: Buffer) => outputChannel.append(b.toString()));
}

 * Nested activation function. Other source control extensions use this patten, though I can't
 * say I'm clear on the advantages of it.

 * Nested activation function which is only run after the configuration has been checked and the extension
 * is confirmed to be enabled.

 * @param config The extension configuration

async function _activate (context: vscode.ExtensionContext, disposables: vscode.Disposable[]) {

async function _activate (_context: vscode.ExtensionContext, config: vscode.WorkspaceConfiguration, disposables: vscode.Disposable[]) {

  const config = vscode.workspace.getConfiguration("pijul");
  const enabled = config.get<boolean>("enabled");

  if (enabled) {
    console.log("test");
  } else {
    // Wait for a configuration change which enables the extension
  }

  await checkPijulInstallation(config, outputChannel);

  await _activate(context, disposables).catch(err => console.error(err));

  const config = vscode.workspace.getConfiguration("pijul");
  const enabled = config.get<boolean>("enabled");
  if (enabled) {
    await _activate(context, config, disposables).catch(err => console.error(err));
  } else {
    // TODO: Wait for a configuration change which enables the extension
  }