import type { ComputedRef, InjectionKey, ConcreteComponent } from 'vue';
import {
  watch,
  computed,
  inject,
  provide,
  ref,
  onBeforeUnmount,
  getCurrentInstance,
  defineComponent,
} from 'vue';
import devWarning from '../vc-util/devWarning';

export type FormItemContext = {
  id: ComputedRef<string>;
  onFieldBlur: () => void;
  onFieldChange: () => void;
  clearValidate: () => void;
};

type InternalFormItemContext = {
  addFormItemField: (key: Symbol, type: ConcreteComponent) => void;
  removeFormItemField: (key: Symbol) => void;
};

const ContextKey: InjectionKey<FormItemContext> = Symbol('ContextProps');

const InternalContextKey: InjectionKey<InternalFormItemContext> = Symbol('InternalContextProps');

export const useProvideFormItemContext = (
  props: FormItemContext,
  useValidation: ComputedRef<boolean> = computed(() => true),
) => {
  const formItemFields = ref(new Map<Symbol, ConcreteComponent>());
  const addFormItemField = (key: Symbol, type: ConcreteComponent) => {
    formItemFields.value.set(key, type);
    formItemFields.value = new Map(formItemFields.value);
  };
  const removeFormItemField = (key: Symbol) => {
    formItemFields.value.delete(key);
    formItemFields.value = new Map(formItemFields.value);
  };
  const instance = getCurrentInstance();
  watch([useValidation, formItemFields], () => {
    if (process.env.NODE_ENV !== 'production') {
      if (useValidation.value && formItemFields.value.size > 1) {
        devWarning(
          false,
          'Form.Item',
          `FormItem can only collect one field item, you haved set ${[
            ...formItemFields.value.values(),
          ]
            .map(v => `\`${v.name}\``)
            .join(', ')} ${formItemFields.value.size} field items.
        You can set not need to be collected fields into \`a-form-item-rest\``,
        );
        let cur = instance;
        while (cur.parent) {
          console.warn('at', cur.type);
          cur = cur.parent;
        }
      }
    }
  });
  provide(ContextKey, props);
  provide(InternalContextKey, {
    addFormItemField,
    removeFormItemField,
  });
};

const defaultContext: FormItemContext = {
  id: computed(() => undefined),
  onFieldBlur: () => {},
  onFieldChange: () => {},
  clearValidate: () => {},
};
const defaultInternalContext: InternalFormItemContext = {
  addFormItemField: () => {},
  removeFormItemField: () => {},
};
export const useInjectFormItemContext = () => {
  const internalContext = inject(InternalContextKey, defaultInternalContext);
  const formItemFieldKey = Symbol('FormItemFieldKey');
  const instance = getCurrentInstance();
  internalContext.addFormItemField(formItemFieldKey, instance.type);
  onBeforeUnmount(() => {
    internalContext.removeFormItemField(formItemFieldKey);
  });
  // We should prevent the passing of context for children
  provide(InternalContextKey, defaultInternalContext);
  provide(ContextKey, defaultContext);
  return inject(ContextKey, defaultContext);
};

export default defineComponent({
  name: 'AFormItemRest',
  setup(_, { slots }) {
    provide(InternalContextKey, defaultInternalContext);
    provide(ContextKey, defaultContext);
    return () => {
      return slots.default?.();
    };
  },
});