(function () {
    window._openVSelect = null;

    requestAnimationFrame(e => {
        document.body.addEventListener('click', ev => {
            if (window._openVSelect && ev.target.closest('v-select') !== window._openVSelect) {
                window._openVSelect.toggle(false);
            }
        })
    })

    class VSelectElement extends HTMLElement {
        constructor() {
            super();
            let self = this;
            self.rawValue = "";
            self.setAttribute('tabindex', '0');
            requestAnimationFrame(() => {
                self.update();
            })
        }

        get value() {
            return this._value;
        }

        set value(value) {
            this._value = value;
            this.dispatchEvent(new Event('input'));
        }


        get required() {
            return this.hasAttribute('required');
        }

        set required(flag) {
            this.toggleAttribute('required', Boolean(flag));
        }

        get name() {
            return this.getAttribute('name');
        }

        set name(val) {
            this.toggleAttribute('name', val);
        }

        get form() {
            return this.closest('form');
        }

        get options() {
            return $$('v-options v-option', this);
        }

        get selected() {
            return $$('v-options v-option[selected]', this);
        }

        connectedCallback() {
            /*            const selected = this.selected;
                        if (selected) return;*/
            const options = Array.prototype.slice.call(this.options);
            const values = this.dataset.value ? this.dataset.value.split(",") : [""];
            if (values.length === 1 && values[0].trim() === '') {
                return;
            }
            options
                .filter(item => values.indexOf(item.getAttribute('value')) !== -1)
                .forEach(item => item.setAttribute('selected', 'true'));
        }

        update() {
            let selected = [],
                lbl = $('v-label', this),
                fd = new FormData();
            this.selected.forEach(e => {
                selected.push(e.innerText);
                fd.append(this.name, e.value);
            })
            if (lbl.attributeChangedCallback) {
                lbl.attributeChangedCallback('value', '', selected.join(", "));
            }
            this.isValid = !(this.required && selected.length === 0);
            this.rawValue = selected.join(", ");
            this.value = fd;
        }

        checkValidity() {
            return this.isValid;
        }

        toggle(open) {
            if (window._openVSelect && window._openVSelect.toggleSelect && open) {
                window._openVSelect.toggleSelect(false);
            }
            const options = $('v-options', this);
            if (!open || this.isOpen) {
                options.style.maxHeight = '0';
                window._openVSelect = false;
                this.isOpen = false;
                this.update();
            } else {
                options.focus();
                let height = 0,
                    children = options.children;
                for (let i = 0; i < children.length; i++) {
                    height += children[i].offsetHeight;
                }
                options.style.maxHeight = height + 'px';
                window._openVSelect = this;
                this.isOpen = true;
            }
            let l = $('v-label', this).classList;
            if (this.isOpen) {
                l.add('open');
            } else {
                l.remove('open');
            }
        }
    }

    class VSelectOptionElement extends HTMLElement {
        constructor() {
            super();
            this._value = this.getAttribute('value');
            this.addEventListener('click', e => {
                let parent = this.parentNode.parentNode,
                    select = !this.selected;
                if (!parent.hasAttribute('multiple')) {
                    parent.toggle(false);
                    for (let item of parent.selected) {
                        if (item !== this) {
                            item.removeAttribute('selected');
                        }
                    }
                }
                if (!this.disabled) {
                    this.attributeChangedCallback('selected', false, select, true);
                    this.parentNode.parentNode.update();
                }
            });
            this.createNew('div', {classes: ['ripple']});
        }

        static get observedAttributes() {
            return ['selected', 'disabled', 'value'];
        }

        get value() {
            return this._value;
        }

        set value(value) {
            this._value = value;
        }

        attributeChangedCallback(name, oldValue, newValue, force) {
            if (name === 'selected' && this.hasAttribute('disabled')) {
                this.removeAttribute(name);
                return;
            }
            if (name === 'disabled' && newValue === true && this.hasAttribute('selected')) {
                this.attributeChangedCallback('selected', false, false);
            }

            if (force) {
                if (newValue) {
                    this.setAttribute(name, newValue);
                } else {
                    this.removeAttribute(name);
                }
            }
            this[name] = newValue;
        }
    }

    class VLabel extends HTMLElement {
        constructor() {
            super();
            this.span = this.createNew('span');
            this.createNew('div', {classes: ['ripple']});
            this.empty = this.getAttribute('empty') || "";
            this.span.innerHTML = this.getAttribute("value") || this.empty;
            this.addEventListener('click', this.openPopUp.bind(this));
        }

        static get observedAttributes() {
            return ['empty', 'value'];
        }

        openPopUp() {
            this.parentNode.toggle(true);
        }

        attributeChangedCallback(name, oldValue, newValue) {
            if (name === 'value') {
                this.span.innerHTML = newValue || this.empty;
            }
            this[name] = newValue;
        }
    }

    customElements.define("v-label", VLabel);
    customElements.define("v-option", VSelectOptionElement);
    customElements.define("v-select", VSelectElement);
})();