/* global requirejs, require */

var classify = Ember.String.classify;
var get = Ember.get;

var LOADING_WHITELIST = ['badges', 'userActivity', 'userPrivateMessages', 'admin', 'adminFlags',
                         'user', 'preferences', 'adminEmail', 'adminUsersList'];
var _dummyRoute;
var _loadingView;

function loadingResolver(cb) {
  return function(parsedName) {
    var fullNameWithoutType = parsedName.fullNameWithoutType;

    if (fullNameWithoutType.indexOf('Loading') >= 0) {
      fullNameWithoutType = fullNameWithoutType.replace('Loading', '');
      if (LOADING_WHITELIST.indexOf(fullNameWithoutType) !== -1) {
        return cb(fullNameWithoutType);
      }
    }
  };
}

function parseName(fullName) {
  const nameParts = fullName.split(":"),
        type = nameParts[0], fullNameWithoutType = nameParts[1],
        name = fullNameWithoutType,
        namespace = get(this, 'namespace'),
        root = namespace;

  return {
    fullName: fullName,
    type: type,
    fullNameWithoutType: fullNameWithoutType,
    name: name,
    root: root,
    resolveMethodName: "resolve" + classify(type)
  };
}

export function buildResolver(baseName) {
  return Ember.DefaultResolver.extend({
    parseName,

    resolveRouter(parsedName) {
      const routerPath = `${baseName}/router`;
      if (requirejs.entries[routerPath]) {
        const module = require(routerPath, null, null, true);
        return module.default;
      }
      return this._super(parsedName);
    },

    normalize(fullName) {
      const split = fullName.split(':');
      if (split.length > 1) {
        const appBase = `${baseName}/${split[0]}s/`;
        const adminBase = 'admin/' + split[0] + 's/';

        // Allow render 'admin/templates/xyz' too
        split[1] = split[1].replace('.templates', '').replace('/templates', '');

        // Try slashes
        let dashed = Ember.String.dasherize(split[1].replace(/\./g, '/'));
        if (requirejs.entries[appBase + dashed] || requirejs.entries[adminBase + dashed]) {
          return split[0] + ":" + dashed;
        }

        // Try with dashes instead of slashes
        dashed = Ember.String.dasherize(split[1].replace(/\./g, '-'));
        if (requirejs.entries[appBase + dashed] || requirejs.entries[adminBase + dashed]) {
          return split[0] + ":" + dashed;
        }
      }
      return this._super(fullName);
    },

    customResolve(parsedName) {
      // If we end with the name we want, use it. This allows us to define components within plugins.
      const suffix = parsedName.type + 's/' + parsedName.fullNameWithoutType,
            dashed = Ember.String.dasherize(suffix),
            moduleName = Object.keys(requirejs.entries).find(function(e) {
              return (e.indexOf(suffix, e.length - suffix.length) !== -1) ||
                     (e.indexOf(dashed, e.length - dashed.length) !== -1);
            });

      var module;
      if (moduleName) {
        module = require(moduleName, null, null, true /* force sync */);
        if (module && module['default']) { module = module['default']; }
      }
      return module;
    },

    resolveWidget(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveAdapter(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveModel(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveView(parsedName) {
      return this.findLoadingView(parsedName) || this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveHelper(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveController(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveComponent(parsedName) {
      return this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveRoute(parsedName) {
      return this.findLoadingRoute(parsedName) || this.customResolve(parsedName) || this._super(parsedName);
    },

    resolveTemplate(parsedName) {
      return this.findPluginMobileTemplate(parsedName) ||
             this.findPluginTemplate(parsedName) ||
             this.findMobileTemplate(parsedName) ||
             this.findTemplate(parsedName) ||
             Ember.TEMPLATES.not_found;
    },

    findLoadingRoute: loadingResolver(function() {
      _dummyRoute = _dummyRoute || Ember.Route.extend();
      return _dummyRoute;
    }),

    findLoadingView: loadingResolver(function() {
      if (!_loadingView) {
        _loadingView = require('discourse/views/loading', null, null, true /* force sync */);
        if (_loadingView && _loadingView['default']) { _loadingView = _loadingView['default']; }
      }
      return _loadingView;
    }),

    findPluginTemplate(parsedName) {
      var pluginParsedName = this.parseName(parsedName.fullName.replace("template:", "template:javascripts/"));
      return this.findTemplate(pluginParsedName);
    },

    findPluginMobileTemplate(parsedName) {
      if (this.mobileView) {
        var pluginParsedName = this.parseName(parsedName.fullName.replace("template:", "template:javascripts/mobile/"));
        return this.findTemplate(pluginParsedName);
      }
    },

    findMobileTemplate(parsedName) {
      if (this.mobileView) {
        var mobileParsedName = this.parseName(parsedName.fullName.replace("template:", "template:mobile/"));
        return this.findTemplate(mobileParsedName);
      }
    },

    findTemplate(parsedName) {
      const withoutType = parsedName.fullNameWithoutType,
            slashedType = withoutType.replace(/\./g, '/'),
            decamelized = withoutType.decamelize(),
            dashed = decamelized.replace(/\./g, '-').replace(/\_/g, '-'),
            templates = Ember.TEMPLATES;

      return this._super(parsedName) ||
             templates[slashedType] ||
             templates[withoutType] ||
             templates[dashed] ||
             templates[decamelized.replace(/\./, '/')] ||
             templates[decamelized.replace(/\_/, '/')] ||
             templates[`${baseName}/templates/${withoutType}`] ||
             this.findAdminTemplate(parsedName) ||
             this.findUnderscoredTemplate(parsedName);
    },

    findUnderscoredTemplate(parsedName) {
      var decamelized = parsedName.fullNameWithoutType.decamelize();
      var underscored = decamelized.replace(/\-/g, "_");
      return Ember.TEMPLATES[underscored];
    },

    // Try to find a template within a special admin namespace, e.g. adminEmail => admin/templates/email
    // (similar to how discourse lays out templates)
    findAdminTemplate(parsedName) {
      var decamelized = parsedName.fullNameWithoutType.decamelize();

      if (decamelized.indexOf('components') === 0) {
        const compTemplate = Ember.TEMPLATES['admin/templates/' + decamelized];
        if (compTemplate) { return compTemplate; }
      }

      if (decamelized === "javascripts/admin") {
        return Ember.TEMPLATES['admin/templates/admin'];
      }

      if (decamelized.indexOf('admin') === 0 || decamelized.indexOf('javascripts/admin') === 0) {
        decamelized = decamelized.replace(/^admin\_/, 'admin/templates/');
        decamelized = decamelized.replace(/^admin\./, 'admin/templates/');
        decamelized = decamelized.replace(/\./g, '_');

        const dashed = decamelized.replace(/_/g, '-');
        return Ember.TEMPLATES[decamelized] ||
               Ember.TEMPLATES[dashed] ||
               Ember.TEMPLATES[dashed.replace('admin-', 'admin/')];
      }
    }

  });
}
