'use strict';

const api = require('../api.js');
const router = require('../router.js');
const misc = require('../util/misc.js');
const topNavigation = require('../models/top_navigation.js');
const Post = require('../models/post.js');
const PostUploadView = require('../views/post_upload_view.js');
const EmptyView = require('../views/empty_view.js');

class PostUploadController {
    constructor() {
        this._lastPromise = null;

        if (!api.hasPrivilege('posts:create')) {
            this._view = new EmptyView();
            this._view.showError('You don\'t have privileges to upload posts.');
            return;
        }

        topNavigation.activate('upload');
        topNavigation.setTitle('Upload');
        this._view = new PostUploadView({
            canUploadAnonymously: api.hasPrivilege('posts:create:anonymous'),
        });
        this._view.addEventListener('change', e => this._evtChange(e));
        this._view.addEventListener('submit', e => this._evtSubmit(e));
        this._view.addEventListener('cancel', e => this._evtCancel(e));
    }

    _evtChange(e) {
        if (e.detail.uploadables.length) {
            misc.enableExitConfirmation();
        } else {
            misc.disableExitConfirmation();
        }
        this._view.clearMessages();
    }

    _evtCancel(e) {
        if (this._lastPromise) {
            this._lastPromise.abort();
        }
    }

    _evtSubmit(e) {
        this._view.disableForm();
        this._view.clearMessages();

        e.detail.uploadables.reduce((promise, uploadable) => {
            return promise.then(() => {
                let post = new Post();
                post.safety = uploadable.safety;
                if (uploadable.url) {
                    post.newContentUrl = uploadable.url;
                } else {
                    post.newContent = uploadable.file;
                }

                let modelPromise = post.save(uploadable.anonymous);
                this._lastPromise = modelPromise;

                return modelPromise
                    .then(() => {
                        this._view.removeUploadable(uploadable);
                        return Promise.resolve();
                    }).catch(errorMessage => {
                        // XXX:
                        // lame, API eats error codes so we need to match
                        // messages instead
                        if (e.detail.skipDuplicates &&
                                errorMessage.match(/already uploaded/)) {
                            return Promise.resolve();
                        }
                        return Promise.reject(errorMessage);
                    });
            });
        }, Promise.resolve())

            .then(() => {
                misc.disableExitConfirmation();
                const ctx = router.show('/posts');
                ctx.controller.showSuccess('Posts uploaded.');
            }, errorMessage => {
                this._view.showError(errorMessage);
                this._view.enableForm();
                return Promise.reject();
            });
    }
}

module.exports = router => {
    router.enter('/upload', (ctx, next) => {
        ctx.controller = new PostUploadController();
    });
};