/* global atom */

'use strict';

var beautifyJS = require('js-beautify');
var beautifyHTML = require('js-beautify').html;
var beautifyCSS = require('js-beautify').css;
var fs = require('fs');
var path = require('path');
var nopt = require('nopt');
var extend = require('extend');
var _ = require('lodash');
var shjs = require('shelljs');

// TODO: Copied from jsbeautify, please update it from time to time
var knownOpts = {
  // Beautifier
  'indent_size': Number,
  'indent_char': String,
  'indent_level': Number,
  'indent_with_tabs': Boolean,
  'preserve_newlines': Boolean,
  'max_preserve_newlines': Number,
  'space_in_paren': Boolean,
  'jslint_happy': Boolean,
  // TODO: expand-strict is obsolete, now identical to expand.  Remove in future version
  'brace_style': ['collapse', 'expand', 'end-expand', 'expand-strict'],
  'break_chained_methods': Boolean,
  'keep_array_indentation': Boolean,
  'unescape_strings': Boolean,
  'wrap_line_length': Number,
  'e4x': Boolean,
  // HTML-only
  'max_char': Number, // obsolete since 1.3.5
  'unformatted': [String, Array],
  'indent_inner_html': [Boolean],
  'indent_scripts': ['keep', 'separate', 'normal'],
  // CLI
  'version': Boolean,
  'help': Boolean,
  'files': [path, Array],
  'outfile': path,
  'replace': Boolean,
  'quiet': Boolean,
  'type': ['js', 'css', 'html'],
  'config': path
};

var Subscriber = require('emissary').Subscriber;
var plugin = module.exports;
Subscriber.extend(plugin);

function getUserHome() {
  return process.env.HOME || process.env.HOMEPATH || process.env.USERPROFILE;
}

function cleanOptions(data, types) {
  nopt.clean(data, types);
  return data;
}

function getCursors(editor) {
  var cursors = editor.getCursors();
  var posArray = [];
  for (var idx = 0; idx < cursors.length; idx++) {
    var cursor = cursors[idx];
    var bufferPosition = cursor.getBufferPosition();
    posArray.push([bufferPosition.row, bufferPosition.column]);
  }
  return posArray;
}

function setCursors(editor, posArray) {
  for (var idx = 0; idx < posArray.length; idx++) {
    var bufferPosition = posArray[idx];
    if (idx === 0) {
      editor.setCursorBufferPosition(bufferPosition);
      continue;
    }
    editor.addCursorAtBufferPosition(bufferPosition);
  }
}

// Storage for memoized results from find file
// Should prevent lots of directory traversal &
// lookups when liniting an entire project
var findFileResults = {};

/**
 * Searches for a file with a specified name starting with
 * 'dir' and going all the way up either until it finds the file
 * or hits the root.
 *
 * @param {string} name filename to search for (e.g. .jshintrc)
 * @param {string} dir  directory to start search from (default:
 *                      current working directory)
 *
 * @returns {string} normalized filename
 */
function findFile(name, dir) {
  dir = dir || process.cwd();

  var filename = path.normalize(path.join(dir, name));
  if (findFileResults[filename] !== undefined) {
    return findFileResults[filename];
  }

  var parent = path.resolve(dir, '../');

  if (shjs.test('-e', filename)) {
    findFileResults[filename] = filename;
    return filename;
  }

  if (dir === parent) {
    findFileResults[filename] = null;
    return null;
  }

  return findFile(name, parent);
}

/**
 * Tries to find a configuration file in either project directory
 * or in the home directory. Configuration files are named
 * '.jshintrc'.
 *
 * @param {string} config   name of the configuration file
 * @param {string} file     path to the file to be linted
 * @returns {string} a path to the config file
 */
function findConfig(config, file) {
  var dir = path.dirname(path.resolve(file));
  var envs = getUserHome();
  var home = path.normalize(path.join(envs, config));

  var proj = findFile(config, dir);
  if (proj) {
    return proj;
  }

  if (shjs.test('-e', home)) {
    return home;
  }

  return null;
}

function beautify() {

  var text;
  var editor = atom.workspace.getActiveEditor();
  var isSelection = !! editor.getSelectedText();
  var softTabs = editor.softTabs;
  var tabLength = editor.getTabLength();

  var defaultOptions = {
    'indent_size': softTabs ? tabLength : 1,
    'indent_char': softTabs ? ' ' : '\t',
    'indent_with_tabs': !softTabs
  };

  // Look for .jsbeautifierrc in file and home path, check env variables
  var editedFilePath = editor.getPath();

  function getConfig(startPath) {
    // Get the path to the config file
    var configPath = findConfig('.jsbeautifyrc', startPath);

    var externalOptions;
    if (configPath) {
      var strip = require('strip-json-comments');
      try {
        externalOptions = JSON.parse(strip(fs.readFileSync(configPath, {
          encoding: 'utf8'
        })));
      } catch (e) {
        externalOptions = {};
      }
    } else {
      externalOptions = {};
    }
    return externalOptions;
  }

  // Get the path to the config file
  var projectOptions = getConfig(editedFilePath);
  var homeOptions = getConfig(getUserHome());

  if (isSelection) {
    text = editor.getSelectedText();
  } else {
    text = editor.getText();
  }
  var oldText = text;

  // All of the options
  // Listed in order from default (base) to the one with the highest priority
  // Left = Default, Right = Will override the left.
  var allOptions = [defaultOptions, homeOptions, projectOptions];

  function getOptions(selection, allOptions) {

    // Reduce all options into correctly merged options.
    var options = _.reduce(allOptions, function(result, currOptions) {

      var containsNested = false;
      var collectedConfig = {};
      var key;

      // Check to see if config file uses nested object format to split up js/css/html options
      for (key in currOptions) {
        if (typeof currOptions[key] === 'object') {
          containsNested = true;
          break; // Found, break out of loop, no need to continue
        }
      }

      // Create a flat object of config options if nested format was used
      if (!containsNested) {
        collectedConfig = currOptions;
      } else {
        // Merge with selected options
        // this == `selected`, where `selected` could be `html`, `js`, 'css', etc
        _.merge(collectedConfig, currOptions[this]);
      }

      return extend(result, collectedConfig);

    }, {}, selection);

    // Clean
    options = cleanOptions(options, knownOpts);
    return options;
  }

  switch (editor.getGrammar().name) {
  case 'JavaScript':
    text = beautifyJS(text, getOptions('js', allOptions));
    break;
  case 'HTML (Liquid)':
  case 'HTML':
  case 'XML':
    text = beautifyHTML(text, getOptions('html', allOptions));
    break;
  case 'CSS':
    text = beautifyCSS(text, getOptions('css', allOptions));
    break;
  default:
    return;
  }
  if (oldText !== text) {
    var posArray = getCursors(editor);
    var origScrollTop = editor.getScrollTop();
    if (isSelection) {
      editor.setTextInBufferRange(
        editor.getSelectedBufferRange(),
        text
      );
    } else {
      editor.setText(text);
    }
    setCursors(editor, posArray);
    // Let the scrollTop setting run after all the save related stuff is run,
    // otherwise setScrollTop is not working, probably because the cursor
    // addition happens asynchronously
    setTimeout(function () {
      editor.setScrollTop(origScrollTop);
    }, 0);
  }
}

function handleSaveEvent() {
  atom.workspace.eachEditor(function (editor) {
    var buffer = editor.getBuffer();
    plugin.unsubscribe(buffer);

    if (atom.config.get('atom-beautify.beautifyOnSave')) {
      var events = 'will-be-saved';
      plugin.subscribe(buffer, events, beautify);
    }
  });
}

plugin.configDefaults = {
  beautifyOnSave: false
};

plugin.activate = function () {
  handleSaveEvent();
  plugin.subscribe(atom.config.observe(
    'atom-beautify.beautifyOnSave',
    handleSaveEvent));
  return atom.workspaceView.command('beautify', beautify);
};