/*******************************
         Install Task
*******************************/

/*
   Install tasks

   For more notes

   * Runs automatically after npm update (hooks)
   * (NPM) Install - Will ask for where to put semantic (outside pm folder)
   * (NPM) Upgrade - Will look for semantic install, copy over files and update if new version
   * Standard installer runs asking for paths to site files etc

*/

let
  gulp           = require('gulp'),
  // node dependencies
  console        = require('better-console'),
  extend         = require('extend'),
  fs             = require('fs'),
  mkdirp         = require('mkdirp'),
  path           = require('path'),

  // gulp dependencies
  chmod          = require('gulp-chmod'),
  del            = require('del'),
  jsonEditor     = require('gulp-json-editor'),
  plumber        = require('gulp-plumber'),
  prompt         = require('prompt-sui'),
  rename         = require('gulp-rename'),
  replace        = require('gulp-replace'),
  requireDotFile = require('require-dot-file'),
  wrench         = require('wrench-sui'),

  runSequence    = require('gulp4-run-sequence'),

  // install config
  install        = require('./config/project/install'),

  // user config
  config         = require('./config/user'),

  // release config (name/title/etc)
  release        = require('./config/project/release'),

  // shorthand
  questions      = install.questions,
  files          = install.files,
  folders        = install.folders,
  regExp         = install.regExp,
  settings       = install.settings,
  source         = install.source,

  installer
;

installer = function (callback) {

  let
    currentConfig = requireDotFile('semantic.json'),
    manager       = install.getPackageManager(),
    rootQuestions = questions.root,
    installFolder = false,
    answers
  ;

  console.clear();

  /* Test NPM install
  manager = {
    name : 'NPM',
    root : path.normalize(__dirname + '/../')
  };
  */


  /* Don't do end user config if SUI is a sub-module */
  if( install.isSubModule() ) {
    console.info('SUI is a sub-module, skipping end-user install');
    return;
  }

  /*-----------------
      Update SUI
  -----------------*/

  // run update scripts if semantic.json exists
  if(currentConfig && manager.name === 'NPM') {

    let
      updateFolder = path.join(manager.root, currentConfig.base),
      updatePaths  = {
        config       : path.join(manager.root, files.config),
        tasks        : path.join(updateFolder, folders.tasks),
        themeImport  : path.join(updateFolder, folders.themeImport),
        definition   : path.join(currentConfig.paths.source.definitions),
        site         : path.join(currentConfig.paths.source.site),
        theme        : path.join(currentConfig.paths.source.themes),
        defaultTheme : path.join(currentConfig.paths.source.themes, folders.defaultTheme)
      }
    ;

    // duck-type if there is a project installed
    if( fs.existsSync(updatePaths.definition) ) {

      // perform update if new version
      if(currentConfig.version !== release.version) {
        console.log('Updating Semantic UI from ' + currentConfig.version + ' to ' + release.version);

        console.info('Updating ui definitions...');
        wrench.copyDirSyncRecursive(source.definitions, updatePaths.definition, settings.wrench.overwrite);

        console.info('Updating default theme...');
        wrench.copyDirSyncRecursive(source.themes, updatePaths.theme, settings.wrench.merge);
        wrench.copyDirSyncRecursive(source.defaultTheme, updatePaths.defaultTheme, settings.wrench.overwrite);

        console.info('Updating tasks...');
        wrench.copyDirSyncRecursive(source.tasks, updatePaths.tasks, settings.wrench.overwrite);

        console.info('Updating gulpfile.js');
        gulp.src(source.userGulpFile)
          .pipe(plumber())
          .pipe(gulp.dest(updateFolder))
        ;

        // copy theme import
        console.info('Updating theme import file');
        gulp.src(source.themeImport)
          .pipe(plumber())
          .pipe(gulp.dest(updatePaths.themeImport))
        ;

        console.info('Adding new site theme files...');
        wrench.copyDirSyncRecursive(source.site, updatePaths.site, settings.wrench.merge);

        console.info('Updating version...');

        // update version number in semantic.json
        gulp.src(updatePaths.config)
          .pipe(plumber())
          .pipe(rename(settings.rename.json)) // preserve file extension
          .pipe(jsonEditor({
            version: release.version
          }))
          .pipe(gulp.dest(manager.root))
        ;

        console.info('Update complete! Run "\x1b[92mgulp build\x1b[0m" to rebuild dist/ files.');

        return;
      }
      else {
        console.log('Current version of Semantic UI already installed');
        return;
      }

    }
    else {
      console.error('Cannot locate files to update at path: ', updatePaths.definition);
      console.log('Running installer');
    }

  }

  /*--------------
   Determine Root
  ---------------*/

  // PM that supports Build Tools (NPM Only Now)
  if(manager.name == 'NPM') {
    rootQuestions[0].message = rootQuestions[0].message
      .replace('{packageMessage}', 'We detected you are using ' + manager.name + ' Nice!')
      .replace('{root}', manager.root)
    ;
    // set default path to detected PM root
    rootQuestions[0].default = manager.root;
    rootQuestions[1].default = manager.root;

    // insert PM questions after "Install Type" question
    Array.prototype.splice.apply(questions.setup, [2, 0].concat(rootQuestions));

    // omit cleanup questions for managed install
    questions.cleanup = [];
  }


  /*--------------
     Create SUI
  ---------------*/

  gulp.task('run setup', function() {

    // If auto-install is switched on, we skip the configuration section and simply reuse the configuration from semantic.json
    if(install.shouldAutoInstall()) {
      answers = {
        overwrite    : 'yes',
        install      : 'auto',
        useRoot      : true,
        semanticRoot : currentConfig.base
      };
    }
    else {
      return gulp
        .src('gulpfile.js')
        .pipe(prompt.prompt(questions.setup, function(setupAnswers) {
          // hoist
          answers = setupAnswers;
        }))
      ;
    }
  });

  gulp.task('create install files', function(callback) {

    /*--------------
     Exit Conditions
    ---------------*/

    // if config exists and user specifies not to proceed
    if(answers.overwrite !== undefined && answers.overwrite == 'no') {
      return;
    }
    console.clear();
    if(install.shouldAutoInstall()) {
      console.log('Auto-Installing (Without User Interaction)');
    }
    else {
      console.log('Installing');
    }
    console.log('------------------------------');


    /*--------------
          Paths
    ---------------*/

    let
      installPaths = {
        config            : files.config,
        configFolder      : folders.config,
        site              : answers.site || folders.site,
        themeConfig       : files.themeConfig,
        themeConfigFolder : folders.themeConfig
      }
    ;

    /*--------------
      NPM Install
    ---------------*/

    // Check if PM install
    if(manager && (answers.useRoot || answers.customRoot)) {

      // Set root to custom root path if set
      if(answers.customRoot) {
        if(answers.customRoot === '') {
          console.log('Unable to proceed, invalid project root');
          return;
        }
        manager.root = answers.customRoot;
      }

      // special install paths only for PM install
      installPaths = extend(false, {}, installPaths, {
        definition   : folders.definitions,
        lessImport   : folders.lessImport,
        tasks        : folders.tasks,
        theme        : folders.themes,
        defaultTheme : path.join(folders.themes, folders.defaultTheme),
        themeImport  : folders.themeImport
      });

      // add project root to semantic root
      installFolder = path.join(manager.root, answers.semanticRoot);

      // add install folder to all output paths
      for(let destination in installPaths) {
        if( installPaths.hasOwnProperty(destination) ) {
          // config goes in project root, rest in install folder
          installPaths[destination] = (destination == 'config' || destination == 'configFolder')
            ? path.normalize( path.join(manager.root, installPaths[destination]) )
            : path.normalize( path.join(installFolder, installPaths[destination]) )
          ;
        }
      }

      // create project folders
      try {
        mkdirp.sync(installFolder);
        mkdirp.sync(installPaths.definition);
        mkdirp.sync(installPaths.theme);
        mkdirp.sync(installPaths.tasks);
      }
      catch(error) {
        console.error('NPM does not have permissions to create folders at your specified path. Adjust your folders permissions and run "npm install" again');
      }

      console.log('Installing to \x1b[92m' + answers.semanticRoot + '\x1b[0m');

      console.info('Copying UI definitions');
      wrench.copyDirSyncRecursive(source.definitions, installPaths.definition, settings.wrench.overwrite);

      console.info('Copying UI themes');
      wrench.copyDirSyncRecursive(source.themes, installPaths.theme, settings.wrench.merge);
      wrench.copyDirSyncRecursive(source.defaultTheme, installPaths.defaultTheme, settings.wrench.overwrite);

      console.info('Copying gulp tasks');
      wrench.copyDirSyncRecursive(source.tasks, installPaths.tasks, settings.wrench.overwrite);

      // copy theme import
      console.info('Adding theme files');
      gulp.src(source.themeImport)
        .pipe(plumber())
        .pipe(gulp.dest(installPaths.themeImport))
      ;
      gulp.src(source.lessImport)
        .pipe(plumber())
        .pipe(gulp.dest(installPaths.lessImport))
      ;

      // create gulp file
      console.info('Creating gulpfile.js');
      gulp.src(source.userGulpFile)
        .pipe(plumber())
        .pipe(gulp.dest(installFolder))
      ;

      callback();

    }


    /*--------------
       Site Theme
    ---------------*/

    // Copy _site templates folder to destination
    if( fs.existsSync(installPaths.site) ) {
      console.info('Site folder exists, merging files (no overwrite)', installPaths.site);
    }
    else {
      console.info('Creating site theme folder', installPaths.site);
    }
    wrench.copyDirSyncRecursive(source.site, installPaths.site, settings.wrench.merge);

    /*--------------
      Theme Config
    ---------------*/

    gulp.task('create theme.config', function() {
      let
        // determine path to site theme folder from theme config
        // force CSS path variable to use forward slashes for paths
        pathToSite   = path.relative(path.resolve(installPaths.themeConfigFolder), path.resolve(installPaths.site)).replace(/\\/g,'/'),
        siteVariable = "@siteFolder   : '" + pathToSite + "/';"
      ;

      // rewrite site variable in theme.less
      console.info('Adjusting @siteFolder to: ', pathToSite + '/');

      if(fs.existsSync(installPaths.themeConfig)) {
        console.info('Modifying src/theme.config (LESS config)', installPaths.themeConfig);
        return gulp.src(installPaths.themeConfig)
          .pipe(plumber())
          .pipe(replace(regExp.siteVariable, siteVariable))
          .pipe(gulp.dest(installPaths.themeConfigFolder))
        ;
      }
      else {
        console.info('Creating src/theme.config (LESS config)', installPaths.themeConfig);
        return gulp.src(source.themeConfig)
          .pipe(plumber())
          .pipe(rename({ extname : '' }))
          .pipe(replace(regExp.siteVariable, siteVariable))
          .pipe(gulp.dest(installPaths.themeConfigFolder))
        ;
      }
    });

    /*--------------
      Semantic.json
    ---------------*/

    gulp.task('create semantic.json', function() {

      let
        jsonConfig = install.createJSON(answers)
      ;

      // adjust variables in theme.less
      if( fs.existsSync(installPaths.config) ) {
        console.info('Extending config file (semantic.json)', installPaths.config);
        return gulp.src(installPaths.config)
          .pipe(plumber())
          .pipe(rename(settings.rename.json)) // preserve file extension
          .pipe(jsonEditor(jsonConfig))
          .pipe(gulp.dest(installPaths.configFolder))
        ;
      }
      else {
        console.info('Creating config file (semantic.json)', installPaths.config);
        return gulp.src(source.config)
          .pipe(plumber())
          .pipe(rename({ extname : '' })) // remove .template from ext
          .pipe(jsonEditor(jsonConfig))
          .pipe(gulp.dest(installPaths.configFolder))
        ;
      }

    });

    runSequence(
      'create theme.config',
      'create semantic.json',
      callback
    );

  });

  gulp.task('clean up install', function() {

    // Completion Message
    if(installFolder && !install.shouldAutoInstall()) {
      console.log('\n Setup Complete! \n Installing Peer Dependencies. \x1b[0;31mPlease refrain from ctrl + c\x1b[0m... \n After completion navigate to \x1b[92m' + answers.semanticRoot + '\x1b[0m and run "\x1b[92mgulp build\x1b[0m" to build');
      process.exit(0);
    }
    else {
      console.log('');
      console.log('');
    }

    // If auto-install is switched on, we skip the configuration section and simply build the dependencies
    if(install.shouldAutoInstall()) {
      return gulp.start('build');
    }
    else {
      return gulp
        .src('gulpfile.js')
        .pipe(prompt.prompt(questions.cleanup, function(answers) {
          if(answers.cleanup == 'yes') {
            del(install.setupFiles);
          }
          if(answers.build == 'yes') {
            gulp.start('build');
          }
        }))
      ;
    }


  });

  runSequence(
    'run setup',
    'create install files',
    'clean up install',
    callback
  );

};

/* Export with Metadata */
installer.displayName = 'install';
installer.description = 'Installs semantic';
module.exports = installer;