aiao-io/aiao

import { defineComponent, getCurrentInstance, h, inject, ref, Ref, VNode } from 'vue';

export interface InputProps extends Object {
  modelValue: string | boolean;
}

const UPDATE_VALUE_EVENT = 'update:modelValue';
const MODEL_VALUE = 'modelValue';
const ROUTER_LINK_VALUE = 'routerLink';
const NAV_MANAGER = 'navManager';
const ROUTER_PROP_PREFIX = 'router';

/**
 * Starting in Vue 3.1.0, all properties are
 * added as keys to the props object, even if
 * they are not being used. In order to correctly
 * account for both value props and v-model props,
 * we need to check if the key exists for Vue <3.1.0
 * and then check if it is not undefined for Vue >= 3.1.0.
 * See https://github.com/vuejs/vue-next/issues/3889
 */
const EMPTY_PROP = Symbol();
const DEFAULT_EMPTY_PROP = { default: EMPTY_PROP };

interface NavManager<T = any> {
  navigate: (options: T) => void;
}

const getComponentClasses = (classes: unknown) => {
  return (classes as string)?.split(' ') || [];
};

const getElementClasses = (
  ref: Ref<HTMLElement | undefined>,
  componentClasses: Set<string>,
  defaultClasses: string[] = []
) => {
  return [...Array.from(ref.value?.classList || []), ...defaultClasses].filter(
    (c: string, i, self) => !componentClasses.has(c) && self.indexOf(c) === i
  );
};

/**
 * Create a callback to define a Vue component wrapper around a Web Component.
 *
 * @prop name - The component tag name (i.e. `ion-button`)
 * @prop componentProps - An array of properties on the
 * component. These usually match up with the @Prop definitions
 * in each component's TSX file.
 * @prop customElement - An option custom element instance to pass
 * to customElements.define. Only set if `includeImportCustomElements: true` in your config.
 * @prop modelProp - The prop that v-model binds to (i.e. value)
 * @prop modelUpdateEvent - The event that is fired from your Web Component when the value changes (i.e. ionChange)
 * @prop externalModelUpdateEvent - The external event to fire from your Vue component when modelUpdateEvent fires. This is used for ensuring that v-model references have been
 * correctly updated when a user's event callback fires.
 */
export const defineContainer = <Props>(
  name: string,
  customElement: any,
  componentProps: string[] = [],
  modelProp?: string,
  modelUpdateEvent?: string,
  externalModelUpdateEvent?: string
) => {
  /**
   * Create a Vue component wrapper around a Web Component.
   * Note: The `props` here are not all properties on a component.
   * They refer to whatever properties are set on an instance of a component.
   */

  if (customElement !== undefined && typeof customElements !== 'undefined' && !customElements.get(name)) {
    customElements.define(name, customElement);
  }

  const Container = defineComponent<Props & InputProps>((props: any, { attrs, slots, emit }) => {
    if (!modelProp) {
      throw new Error('modelProp not found');
    }
    let modelPropValue = props[modelProp];
    const containerRef = ref<HTMLElement>();
    const classes = new Set(getComponentClasses(attrs.class));
    const onVnodeBeforeMount = (vnode: VNode) => {
      // Add a listener to tell Vue to update the v-model
      if (vnode.el) {
        const eventsNames = Array.isArray(modelUpdateEvent) ? modelUpdateEvent : [modelUpdateEvent];
        eventsNames.forEach((eventName: string) => {
          vnode.el!.addEventListener(eventName.toLowerCase(), (e: Event) => {
            modelPropValue = (e?.target as any)[modelProp];
            emit(UPDATE_VALUE_EVENT, modelPropValue);

            /**
             * We need to emit the change event here
             * rather than on the web component to ensure
             * that any v-model bindings have been updated.
             * Otherwise, the developer will listen on the
             * native web component, but the v-model will
             * not have been updated yet.
             */
            if (externalModelUpdateEvent) {
              emit(externalModelUpdateEvent, e);
            }
          });
        });
      }
    };

    const currentInstance = getCurrentInstance();
    const hasRouter = currentInstance?.appContext?.provides[NAV_MANAGER];
    const navManager: NavManager | undefined = hasRouter ? inject(NAV_MANAGER) : undefined;
    const handleRouterLink = (ev: Event) => {
      const { routerLink } = props;
      if (routerLink === EMPTY_PROP) return;

      if (navManager !== undefined) {
        const navigationPayload: any = { event: ev };
        for (const key in props) {
          if (Object.prototype.hasOwnProperty.call(props, key)) {
            const value = props[key];
            if (props.hasOwnProperty(key) && key.startsWith(ROUTER_PROP_PREFIX) && value !== EMPTY_PROP) {
              navigationPayload[key] = value;
            }
          }
        }
        navManager.navigate(navigationPayload);
      } else {
        console.warn('Tried to navigate, but no router was found. Make sure you have mounted Vue Router.');
      }
    };

    return () => {
      modelPropValue = props[modelProp];

      getComponentClasses(attrs.class).forEach(value => {
        classes.add(value);
      });

      const oldClick = props.onClick;
      const handleClick = (ev: Event) => {
        if (oldClick !== undefined) {
          oldClick(ev);
        }
        if (!ev.defaultPrevented) {
          handleRouterLink(ev);
        }
      };

      let propsToAdd: any = {
        ref: containerRef,
        class: getElementClasses(containerRef, classes),
        onClick: handleClick,
        onVnodeBeforeMount: modelUpdateEvent ? onVnodeBeforeMount : undefined
      };

      /**
       * We can use Object.entries here
       * to avoid the hasOwnProperty check,
       * but that would require 2 iterations
       * where as this only requires 1.
       */

      for (const key in props) {
        if (Object.prototype.hasOwnProperty.call(props, key)) {
          const value = props[key];
          if (props.hasOwnProperty(key) && value !== EMPTY_PROP) {
            propsToAdd[key] = value;
          }
        }
      }

      if (modelProp) {
        /**
         * If form value property was set using v-model
         * then we should use that value.
         * Otherwise, check to see if form value property
         * was set as a static value (i.e. no v-model).
         */
        if (props[MODEL_VALUE] !== EMPTY_PROP) {
          propsToAdd = {
            ...propsToAdd,
            [modelProp]: props[MODEL_VALUE]
          };
        } else if (modelPropValue !== EMPTY_PROP) {
          propsToAdd = {
            ...propsToAdd,
            [modelProp]: modelPropValue
          };
        }
      }

      return h(name, propsToAdd, slots.default && slots.default());
    };
  });

  Container.displayName = name;

  Container.props = {
    [ROUTER_LINK_VALUE]: DEFAULT_EMPTY_PROP
  };

  componentProps.forEach(componentProp => {
    Container.props[componentProp] = DEFAULT_EMPTY_PROP;
  });

  if (modelProp) {
    Container.props[MODEL_VALUE] = DEFAULT_EMPTY_PROP;
    Container.emits = [UPDATE_VALUE_EVENT, externalModelUpdateEvent];
  }

  return Container;
};