/**
 * social-share.js
 *
 * @author  52cik <fe.52cik@gmail.com>
 * @license mit
 *
 * @example
 * <pre>
 * socialshare('.share-components');
 *
 * // or
 *
 * socialshare('.share-bar', {
 *     sites: ['qzone', 'qq', 'weibo','wechat'],
 *     // ...
 * });
 * </pre>
 */
;(function (window, document, undefined) {

    // initialize a variables.

    var array$indexof = array.prototype.indexof;
    var object$assign = object.assign;

    var runninginwechat = /micromessenger/i.test(navigator.useragent);
    var ismobilescreen = document.documentelement.clientwidth <= 768;

    var image = (document.images[0] || 0).src || '';
    var site = getmetacontentbyname('site') || getmetacontentbyname('site') || document.title;
    var title = getmetacontentbyname('title') || getmetacontentbyname('title') || document.title;
    var description = getmetacontentbyname('description') || getmetacontentbyname('description') || '';

    var defaults = {
        url: location.href,
        origin: location.origin,
        source: site,
        title: title,
        description: description,
        image: image,
        imageselector: undefined,

        weibokey: '',

        wechatqrcodetitle: '扫一扫',
        wechatqrcodehelper: '<p>分享到你得朋友圈</p>',
        wechatqrcodesize: 100,

        sites: ['weibo', 'qq', 'wechat', 'douban', 'qzone', 'linkedin', 'facebook', 'twitter', 'google'],
        mobilesites: [],
        disabled: [],
        initialized: false
    };

    var templates = {
        qzone: 'http://sns.qzone.qq.com/cgi-bin/qzshare/cgi_qzshare_onekey?url={{url}}&title={{title}}&desc={{description}}&summary={{summary}}&site={{source}}&pics={{image}}',
        qq: 'http://connect.qq.com/widget/shareqq/index.html?url={{url}}&title={{title}}&source={{source}}&desc={{description}}&pics={{image}}&summary="{{summary}}"',
        weibo: 'https://service.weibo.com/share/share.php?url={{url}}&title={{title}}&pic={{image}}&appkey={{weibokey}}',
        wechat: 'javascript:',
        douban: 'http://shuo.douban.com/!service/share?href={{url}}&name={{title}}&text={{description}}&image={{image}}&starid=0&aid=0&style=11',
        linkedin: 'http://www.linkedin.com/sharearticle?mini=true&ro=true&title={{title}}&url={{url}}&summary={{summary}}&source={{source}}&armin=armin',
        facebook: 'https://www.facebook.com/sharer/sharer.php?u={{url}}',
        twitter: 'https://twitter.com/intent/tweet?text={{title}}&url={{url}}&via={{origin}}',
        google: 'https://plus.google.com/share?url={{url}}'
    };


    /**
     * expose api to the global
     *
     * @param  {string|element} elem
     * @param  {object} options
     */
    window.socialshare = function (elem, options) {
        elem = typeof elem === 'string' ? queryselectoralls(elem) : elem;

        if (elem.length === undefined) {
            elem = [elem];
        }

        each(elem, function (el) {
            if (!el.initialized) {
                share(el, options);
            }
        });
    };

    // domready after initialization
    already(function () {
        socialshare('.social-share, .share-component');
    });


    /**
     * initialize a share bar.
     *
     * @param {object}        $options globals (optional).
     *
     * @return {void}
     */
    function share(elem, options) {
        var data = mixin({}, defaults, options || {}, dataset(elem));

        if (data.imageselector) {
            data.image = queryselectoralls(data.imageselector).map(function(item) {
                return item.src;
            }).join('||');
        }

        addclass(elem, 'share-component social-share');
        createicons(elem, data);
        createwechat(elem, data);

        elem.initialized = true;
    }


    /**
     * create site icons
     *
     * @param {element} elem
     * @param {object} data
     */
    function createicons(elem, data) {
        var sites = getsites(data);
        var isprepend = data.mode == 'prepend';

        each(isprepend ? sites.reverse() : sites, function (name) {
            var url = makeurl(name, data);
            var link = data.initialized ? getelementsbyclassname(elem, 'icon-' + name) : createelementbystring('<a class="social-share-icon icon-' + name + '"></a>');

            if (!link.length) {
                return true;
            }

            link[0].href = url;

            if (name === 'wechat') {
                link[0].tabindex = -1;
            } else {
                link[0].target = '_blank';
            }

            if (!data.initialized) {
                isprepend ? elem.insertbefore(link[0], elem.firstchild) : elem.appendchild(link[0]);
            }
        });
    }


    /**
     * create the wechat icon and qrcode.
     *
     * @param {element} elem
     * @param {object} data
     */
    function createwechat (elem, data) {
        var wechat = getelementsbyclassname(elem, 'icon-wechat', 'a');

        if (wechat.length === 0) {
            return false;
        }

        var elems = createelementbystring('<div class="wechat-qrcode"><h4>' + data.wechatqrcodetitle + '</h4><div class="qrcode"></div><div class="help">' + data.wechatqrcodehelper + '</div></div>');
        var qrcode = getelementsbyclassname(elems[0], 'qrcode', 'div');

        new qrcode(qrcode[0], {text: data.url, width: data.wechatqrcodesize, height: data.wechatqrcodesize});
        wechat[0].appendchild(elems[0]);
    }


    /**
     * get available site lists.
     *
     * @param {object} data
     *
     * @returns {array}
     */
    function getsites(data) {
        if (!data['mobilesites'].length) {
            data['mobilesites'] = data['sites'];
        }

        var sites = (ismobilescreen ? data['mobilesites'] : data['sites']).slice(0);
        var disabled = data['disabled'];

        if (typeof sites == 'string') {
            sites = sites.split(/\s*,\s*/);
        }
        if (typeof disabled == 'string') {
            disabled = disabled.split(/\s*,\s*/);
        }

        if (runninginwechat) {
            disabled.push('wechat');
        }

        // remove elements
        disabled.length && each(disabled, function (it) {
            sites.splice(inarray(it, sites), 1);
        });

        return sites;
    }


    /**
     * build the url of icon.
     *
     * @param {string} name
     * @param {object} data
     *
     * @returns {string}
     */
    function makeurl(name, data) {

        if (! data['summary']){
            data['summary'] = data['description'];
        }

        return templates[name].replace(/\{\{(\w)(\w*)\}\}/g, function (m, fix, key) {
            var namekey = name + fix + key.tolowercase();
            key = (fix + key).tolowercase();

            return encodeuricomponent((data[namekey] === undefined ? data[key] : data[namekey]) || '');
        });
    }


    /**
     * supports queryselectorall, jquery, zepto and simple selector.
     *
     * @param str
     *
     * @returns {*}
     */
    function queryselectoralls(str) {
        return (document.queryselectorall || window.jquery || window.zepto || selector).call(document, str);
    }


    /**
     * simple selector.
     *
     * @param {string} str #id or .class
     *
     * @returns {array}
     */
    function selector(str) {
        var elems = [];

        each(str.split(/\s*,\s*/), function(s) {
            var m = s.match(/([#.])(\w+)/);
            if (m === null) {
                throw error('supports only simple single #id or .class selector.');
            }

            if (m[1]) {
                var elem = document.getelementbyid(m[2]);

                if (elem) {
                    elems.push(elem);
                }
            }

            elems = elems.concat(getelementsbyclassname(str));
        });

        return elems;
    }


    /**
     * add the classnames for element.
     *
     * @param {element} elem
     * @param {string} value
     */
    function addclass(elem, value) {
        if (value && typeof value === "string") {
            var classnames = (elem.classname + ' ' + value).split(/\s+/);
            var setclass = ' ';

            each(classnames, function (classname) {
                if (setclass.indexof(' ' + classname + ' ') < 0) {
                    setclass += classname + ' ';
                }
            });

            elem.classname = setclass.slice(1, -1);
        }
    }


    /**
     * get meta element content value
     *
     * @param {string} name
     *
     * @returns {string|*}
     */
    function getmetacontentbyname(name) {
        return (document.getelementsbyname(name)[0] || 0).content;
    }


    /**
     * get elements by classname for ie8-
     *
     * @param {element} elem element
     * @param {string} name classname
     * @param {string} tag tagname
     *
     * @returns {htmlcollection|array}
     */
    function getelementsbyclassname(elem, name, tag) {
        if (elem.getelementsbyclassname) {
            return elem.getelementsbyclassname(name);
        }

        var elements = [];
        var elems = elem.getelementsbytagname(tag || '*');
        name = ' ' + name + ' ';

        each(elems, function (elem) {
            if ((' ' + (elem.classname || '') + ' ').indexof(name) >= 0) {
                elements.push(elem);
            }
        });

        return elements;
    }


    /**
     * create element by string.
     *
     * @param {string} str
     *
     * @returns {nodelist}
     */
    function createelementbystring(str) {
        var div = document.createelement('div');
        div.innerhtml = str;

        return div.childnodes;
    }


    /**
     * merge objects.
     *
     * @returns {object}
     */
    function mixin() {
        var args = arguments;

        if (object$assign) {
            return object$assign.apply(null, args);
        }

        var target = {};

        each(args, function (it) {
            each(it, function (v, k) {
                target[k] = v;
            });
        });

        return args[0] = target;
    }


    /**
     * get dataset object.
     *
     * @param {element} elem
     *
     * @returns {object}
     */
    function dataset(elem) {
        if (elem.dataset) {
            return json.parse(json.stringify(elem.dataset));
        }

        var target = {};

        if (elem.hasattributes()) {
            each(elem.attributes, function (attr) {
                var name = attr.name;
                if (name.indexof('data-') !== 0) {
                    return true;
                }

                name = name.replace(/^data-/i, '')
                    .replace(/-(\w)/g, function (all, letter) {
                        return letter.touppercase();
                    });

                target[name] = attr.value;
            });

            return target;
        }

        return {};
    }


    /**
     * found element in the array.
     *
     * @param {array|object} elem
     * @param {array} arr
     * @param {number} i
     *
     * @returns {number}
     */
    function inarray(elem, arr, i) {
        var len;

        if (arr) {
            if (array$indexof) {
                return array$indexof.call(arr, elem, i);
            }

            len = arr.length;
            i = i ? i < 0 ? math.max(0, len + i) : i : 0;

            for (; i < len; i++) {
                // skip accessing in sparse arrays
                if (i in arr && arr[i] === elem) {
                    return i;
                }
            }
        }

        return -1;
    }


    /**
     * simple each.
     *
     * @param {array|object} obj
     * @param {function} callback
     *
     * @returns {*}
     */
    function each(obj, callback) {
        var length = obj.length;

        if (length === undefined) {
            for (var name in obj) {
                if (obj.hasownproperty(name)) {
                    if (callback.call(obj[name], obj[name], name) === false) {
                        break;
                    }
                }
            }
        } else {
            for (var i = 0; i < length; i++) {
                if (callback.call(obj[i], obj[i], i) === false) {
                    break;
                }
            }
        }
    }


    /**
     * dom ready.
     *
     * @param {function} fn
     *
     * @link https://github.com/jed/already.js
     */
    function already ( fn ) {
        var add = 'addeventlistener';
        var pre = document[ add ] ? '' : 'on';

        ~document.readystate.indexof( 'm' ) ? fn() :
            'load domcontentloaded readystatechange'.replace( /\w+/g, function( type, i ) {
                ( i ? document : window )
                    [ pre ? 'attachevent' : add ]
                (
                    pre + type,
                    function(){ if ( fn ) if ( i < 6 || ~document.readystate.indexof( 'm' ) ) fn(), fn = 0 },
                    !1
                )
            })
    }
})(window, document);