import type OlInteraction from 'ol/interaction/Interaction.js';
import OlMap from 'ol/Map.js';
import {
  getOlcUid,
  getOlcVirtualGroupUid,
  olcUidKey,
  olcVirtualGroupUidKey,
} from '../uid.js';
import { filterObjects, filterObjectsStartsWith, findObject } from '../base.js';

export const DefaultGroupUid = 'olcInteractionGroup';

/**
 * Manage a virtual group of interaction by setting a group uid in every added interaction.
 * It can add, remove, find interaction, and toggle the active state of interactions.
 */
export class InteractionGroup {
  protected readonly map: OlMap;
  protected virtualGroupUid: string;

  constructor(map: OlMap, virtualGroupUid?: string) {
    this.map = map;
    this.virtualGroupUid = virtualGroupUid ?? DefaultGroupUid;
  }

  /**
   * @returns all the interaction of the wanted group.
   */
  getGroupInteractions(): OlInteraction[] {
    return filterObjects(
      this.map.getInteractions().getArray(),
      olcVirtualGroupUidKey,
      this.virtualGroupUid,
    );
  }

  /**
   * Adds the given interaction (with an uid) to the map.
   * The interaction can't be in multiple groups at the same time.
   * @param uid - The uid to associate with the interaction
   * @param interaction - The interaction to add
   */
  add(uid: string, interaction: OlInteraction): void {
    if (this.hasInteraction(uid)) {
      console.warn(
        `Interaction with uid "${uid}" already exists in group "${this.virtualGroupUid}"`,
      );
      return;
    }
    const interactionGroupUid = getOlcVirtualGroupUid(interaction);
    if (interactionGroupUid) {
      console.warn(
        `Interaction with uid "${uid}" already exists in group "${interactionGroupUid}"`,
      );
      return;
    }
    interaction.set(olcUidKey, uid);
    interaction.set(olcVirtualGroupUidKey, this.virtualGroupUid);
    this.map.addInteraction(interaction);
  }

  /**
   * Finds an interaction of this group by its uid.
   * @param uid - The uid of the interaction to find
   * @returns The interaction if found, null otherwise
   */
  find(uid: string): OlInteraction | null {
    return findObject(this.getGroupInteractions(), olcUidKey, uid);
  }

  /**
   * Finds all interaction of this group having their uid starting by the provided prefix.
   * @param uidPrefix - A start part uid of the interaction to find.
   * @returns The interactions if found or an empty array otherwise.
   */
  filterStartsWith(uidPrefix: string): OlInteraction[] {
    return filterObjectsStartsWith(this.getGroupInteractions(), olcUidKey, uidPrefix);
  }

  /**
   * Removes the given interaction from the map.
   * @param uid - The uid of the interaction to remove
   */
  remove(uid: string): void {
    const interaction = this.find(uid);
    if (!interaction) {
      return;
    }
    // Remove the interaction from the map
    interaction.unset(olcVirtualGroupUidKey);
    this.map.removeInteraction(interaction);
  }

  /**
   * Verifies if the interaction is already present in the map
   * @param uid The uid of the interaction to check
   * @returns boolean indicating if the interaction is present
   */
  hasInteraction(uid: string): boolean {
    return this.getGroupInteractions().some(
      (interaction) => getOlcUid(interaction) === uid,
    );
  }

  /**
   * Activate the interaction (and deactivate other interactions of this group) or
   * deactivate it.
   */
  setActive(active: boolean, uid: string) {
    const interaction = this.find(uid);
    if (!interaction) {
      return;
    }
    if (active) {
      this.use(interaction);
    } else {
      interaction.setActive(false);
    }
  }

  /**
   * Deactivate all draw interaction of this group.
   */
  deactivateAll() {
    return this.getGroupInteractions().forEach((interaction) =>
      interaction.setActive(false),
    );
  }

  /**
   * Deactivates and remove every interaction of this group.
   */
  destroy() {
    this.deactivateAll();
    this.getGroupInteractions().forEach((interaction) => {
      this.remove(getOlcUid(interaction) ?? '');
    });
  }

  /**
   * Deactivate all interaction of this group and activate the given one.
   * @protected
   */
  protected use(interaction: OlInteraction) {
    this.deactivateAll();
    interaction.setActive(true);
  }
}