import { action } from "@ember/object";
import { classNames } from "@ember-decorators/component";
import discourseComputed from "discourse-common/utils/decorators";
import { on } from "@ember-decorators/object";
import { empty, reads } from "@ember/object/computed";
import Component from "@ember/component";
import { makeArray } from "discourse-common/lib/helpers";

@classNames("value-list")
export default class ValueList extends Component {
  @empty("newValue") inputInvalid;

  inputDelimiter = null;
  inputType = null;
  newValue = "";
  collection = null;
  values = null;

  @reads("addKey") noneKey;

  @on("didReceiveAttrs")
  _setupCollection() {
    const values = this.values;
    if (this.inputType === "array") {
      this.set("collection", values || []);
      return;
    }

    this.set(
      "collection",
      this._splitValues(values, this.inputDelimiter || "\n")
    );
  }

  @discourseComputed("choices.[]", "collection.[]")
  filteredChoices(choices, collection) {
    return makeArray(choices).filter((i) => !collection.includes(i));
  }

  keyDown(event) {
    if (event.key === "Enter") {
      this.send("addValue", this.newValue);
    }
  }

  @action
  changeValue(index, event) {
    this._replaceValue(index, event.target.value);
  }

  @action
  addValue(newValue) {
    if (this.inputInvalid) {
      return;
    }

    this.set("newValue", null);
    this._addValue(newValue);
  }

  @action
  removeValue(value) {
    this._removeValue(value);
  }

  @action
  selectChoice(choice) {
    this._addValue(choice);
  }

  @action
  shift(operation, index) {
    let futureIndex = index + operation;

    if (futureIndex > this.collection.length - 1) {
      futureIndex = 0;
    } else if (futureIndex < 0) {
      futureIndex = this.collection.length - 1;
    }

    const shiftedValue = this.collection[index];
    this.collection.removeAt(index);
    this.collection.insertAt(futureIndex, shiftedValue);

    this._saveValues();
  }

  _addValue(value) {
    this.collection.addObject(value);

    if (this.choices) {
      this.set("choices", this.choices.rejectBy("id", value));
    } else {
      this.set("choices", []);
    }

    this._saveValues();
  }

  _removeValue(value) {
    this.collection.removeObject(value);

    if (this.choices) {
      this.set("choices", this.choices.concat([value]).uniq());
    } else {
      this.set("choices", makeArray(value));
    }

    this._saveValues();
  }

  _replaceValue(index, newValue) {
    this.collection.replace(index, 1, [newValue]);
    this._saveValues();
  }

  _saveValues() {
    if (this.inputType === "array") {
      this.set("values", this.collection);
      return;
    }

    this.set("values", this.collection.join(this.inputDelimiter || "\n"));
  }

  @discourseComputed("collection")
  showUpDownButtons(collection) {
    return collection.length - 1 ? true : false;
  }

  _splitValues(values, delimiter) {
    if (values && values.length) {
      return values.split(delimiter).filter((x) => x);
    } else {
      return [];
    }
  }
}