module.exports = function(grunt) {

  var fs = require('fs');
  var azureDeploy = require('azure-deploy');

  var pathExists = function(path) {
    try {
      fs.accessSync(path, fs.F_OK);
      return true;
    } catch(e) {
      return false;
    }
  };

  grunt.registerMultiTask('azureDeploy',
                        "Deploys a directory to an Azure website.",
                        function () {

    var options = this.options({
      credential_file: '~/.azure_deploy.json'
    });
    var credFileExists = pathExists(options.credential_file);

    grunt.log.writeln("Validating target data.");
    // 1. Make sure the user has the right directory
    if (typeof this.data.directory === 'undefined') {
      grunt.log.error("Directory isn't specified for this target!");
      return;
    }
    // test for directory existence
    if (!pathExists(this.data.directory)) {
      grunt.log.error("Directory " + this.data.directory + " isn't accessible.");
      return;
    }
    var targetDirectory = this.data.directory;

    // 2. check for valid credentials
    var azureUsername = null;
    var azurePassword = null;
    if (credFileExists) {
      var creds = grunt.file.readJSON(options.credential_file)
      if (typeof creds.username !== 'undefined' &&
          typeof creds.password !== 'undefined') {
        azureUsername = creds.username
        azurePassword = creds.password
      } else {
        grunt.log.error("Couldn't get username and password from credential file.");
        return;
      }
    } else {
      grunt.log.error("I don't have a credential file. Please check that it exists.");
      return;
    }

    // 3. Check for azure username
    if (typeof this.data.website_name === 'undefined') {
      grunt.log.error("Task target does not have a defined Azure website name. We need this!");
      return;
    } else {
      var azureWebsiteName = this.data.website_name;
    }

    var deploymentManager = new azureDeploy.AzureWebSiteDeploymentManager(
      azureWebsiteName, azureUsername, azurePassword);

    grunt.log.writeln("Starting Azure deployment...");

    var done = this.async();
    deploymentManager.deploy(targetDirectory)
    .then(function() {
      grunt.log.ok("Deployment successful.");
      done();
    })
    .catch(function(e) {
      grunt.log.error('Deployment finished with errors.');
      grunt.log.writeln(e);
      done(false);
    });
  });


  // config
  grunt.initConfig({
    azureDeploy: {
      middleman: {
        options: {
          credential_file: './creds.json'
        },
        directory: './build',
        website_name: 'middleman-azure-cdn-test'
      }
    }
  });

};