/**
 * @license
 * Copyright 2016 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

/**
 * Number input field
 *
 * @class
 */
// Former goog.module ID: Blockly.FieldNumber

import {Field} from './field.js';
import * as fieldRegistry from './field_registry.js';
import {
  FieldInput,
  FieldInputConfig,
  FieldInputValidator,
} from './field_input.js';
import * as aria from './utils/aria.js';
import * as dom from './utils/dom.js';

/**
 * Class for an editable number field.
 */
export class FieldNumber extends FieldInput<number> {
  /** The minimum value this number field can contain. */
  protected min_ = -Infinity;

  /** The maximum value this number field can contain. */
  protected max_ = Infinity;

  /** The multiple to which this fields value is rounded. */
  protected precision_ = 0;

  /**
   * The number of decimal places to allow, or null to allow any number of
   * decimal digits.
   */
  private decimalPlaces: number | null = null;

  /** Don't spellcheck numbers.  Our validator does a better job. */
  protected override spellcheck_ = false;

  /**
   * @param value The initial value of the field. Should cast to a number.
   *     Defaults to 0. Also accepts Field.SKIP_SETUP if you wish to skip setup
   *     (only used by subclasses that want to handle configuration and setting
   *     the field value after their own constructors have run).
   * @param min Minimum value. Will only be used if config is not
   *     provided.
   * @param max Maximum value. Will only be used if config is not
   *     provided.
   * @param precision Precision for value. Will only be used if config
   *     is not provided.
   * @param validator A function that is called to validate changes to the
   *     field's value. Takes in a number & returns a validated number, or null
   *     to abort the change.
   * @param config A map of options used to configure the field.
   *     See the [field creation documentation]{@link
   * https://developers.google.com/blockly/guides/create-custom-blocks/fields/built-in-fields/number#creation}
   * for a list of properties this parameter supports.
   */
  constructor(
    value?: string | number | typeof Field.SKIP_SETUP,
    min?: string | number | null,
    max?: string | number | null,
    precision?: string | number | null,
    validator?: FieldNumberValidator | null,
    config?: FieldNumberConfig,
  ) {
    // Pass SENTINEL so that we can define properties before value validation.
    super(Field.SKIP_SETUP);

    if (value === Field.SKIP_SETUP) return;
    if (config) {
      this.configure_(config);
    } else {
      this.setConstraints(min, max, precision);
    }
    this.setValue(value);
    if (validator) {
      this.setValidator(validator);
    }
  }

  /**
   * Configure the field based on the given map of options.
   *
   * @param config A map of options to configure the field based on.
   */
  protected override configure_(config: FieldNumberConfig) {
    super.configure_(config);
    this.setMinInternal(config.min);
    this.setMaxInternal(config.max);
    this.setPrecisionInternal(config.precision);
  }

  /**
   * Set the maximum, minimum and precision constraints on this field.
   * Any of these properties may be undefined or NaN to be disabled.
   * Setting precision (usually a power of 10) enforces a minimum step between
   * values. That is, the user's value will rounded to the closest multiple of
   * precision. The least significant digit place is inferred from the
   * precision. Integers values can be enforces by choosing an integer
   * precision.
   *
   * @param min Minimum value.
   * @param max Maximum value.
   * @param precision Precision for value.
   */
  setConstraints(
    min: number | string | undefined | null,
    max: number | string | undefined | null,
    precision: number | string | undefined | null,
  ) {
    this.setMinInternal(min);
    this.setMaxInternal(max);
    this.setPrecisionInternal(precision);
    this.setValue(this.getValue());
  }

  /**
   * Sets the minimum value this field can contain. Updates the value to
   * reflect.
   *
   * @param min Minimum value.
   */
  setMin(min: number | string | undefined | null) {
    this.setMinInternal(min);
    this.setValue(this.getValue());
  }

  /**
   * Sets the minimum value this field can contain. Called internally to avoid
   * value updates.
   *
   * @param min Minimum value.
   */
  private setMinInternal(min: number | string | undefined | null) {
    if (min == null) {
      this.min_ = -Infinity;
    } else {
      min = Number(min);
      if (!isNaN(min)) {
        this.min_ = min;
      }
    }
  }

  /**
   * Returns the current minimum value this field can contain. Default is
   * -Infinity.
   *
   * @returns The current minimum value this field can contain.
   */
  getMin(): number {
    return this.min_;
  }

  /**
   * Sets the maximum value this field can contain. Updates the value to
   * reflect.
   *
   * @param max Maximum value.
   */
  setMax(max: number | string | undefined | null) {
    this.setMaxInternal(max);
    this.setValue(this.getValue());
  }

  /**
   * Sets the maximum value this field can contain. Called internally to avoid
   * value updates.
   *
   * @param max Maximum value.
   */
  private setMaxInternal(max: number | string | undefined | null) {
    if (max == null) {
      this.max_ = Infinity;
    } else {
      max = Number(max);
      if (!isNaN(max)) {
        this.max_ = max;
      }
    }
  }

  /**
   * Returns the current maximum value this field can contain. Default is
   * Infinity.
   *
   * @returns The current maximum value this field can contain.
   */
  getMax(): number {
    return this.max_;
  }

  /**
   * Sets the precision of this field's value, i.e. the number to which the
   * value is rounded. Updates the field to reflect.
   *
   * @param precision The number to which the field's value is rounded.
   */
  setPrecision(precision: number | string | undefined | null) {
    this.setPrecisionInternal(precision);
    this.setValue(this.getValue());
  }

  /**
   * Sets the precision of this field's value. Called internally to avoid
   * value updates.
   *
   * @param precision The number to which the field's value is rounded.
   */
  private setPrecisionInternal(precision: number | string | undefined | null) {
    this.precision_ = Number(precision) || 0;
    let precisionString = String(this.precision_);
    if (precisionString.includes('e')) {
      // String() is fast.  But it turns .0000001 into '1e-7'.
      // Use the much slower toLocaleString to access all the digits.
      precisionString = this.precision_.toLocaleString('en-US', {
        maximumFractionDigits: 20,
      });
    }
    const decimalIndex = precisionString.indexOf('.');
    if (decimalIndex === -1) {
      // If the precision is 0 (float) allow any number of decimals,
      // otherwise allow none.
      this.decimalPlaces = precision ? 0 : null;
    } else {
      this.decimalPlaces = precisionString.length - decimalIndex - 1;
    }
  }

  /**
   * Returns the current precision of this field. The precision being the
   * number to which the field's value is rounded. A precision of 0 means that
   * the value is not rounded.
   *
   * @returns The number to which this field's value is rounded.
   */
  getPrecision(): number {
    return this.precision_;
  }

  /**
   * Ensure that the input value is a valid number (must fulfill the
   * constraints placed on the field).
   *
   * @param newValue The input value.
   * @returns A valid number, or null if invalid.
   */
  protected override doClassValidation_(
    newValue?: AnyDuringMigration,
  ): number | null {
    if (newValue === null) {
      return null;
    }

    // Clean up text.
    newValue = `${newValue}`;
    // TODO: Handle cases like 'ten', '1.203,14', etc.
    // 'O' is sometimes mistaken for '0' by inexperienced users.
    newValue = newValue.replace(/O/gi, '0');
    // Strip out thousands separators.
    newValue = newValue.replace(/,/g, '');
    // Ignore case of 'Infinity'.
    newValue = newValue.replace(/infinity/i, 'Infinity');

    // Clean up number.
    let n = Number(newValue || 0);
    if (isNaN(n)) {
      // Invalid number.
      return null;
    }
    // Get the value in range.
    n = Math.min(Math.max(n, this.min_), this.max_);
    // Round to nearest multiple of precision.
    if (this.precision_ && isFinite(n)) {
      n = Math.round(n / this.precision_) * this.precision_;
    }
    // Clean up floating point errors.
    if (this.decimalPlaces !== null) {
      n = Number(n.toFixed(this.decimalPlaces));
    }
    return n;
  }

  /**
   * Create the number input editor widget.
   *
   * @returns The newly created number input editor.
   */
  protected override widgetCreate_(): HTMLInputElement {
    const htmlInput = super.widgetCreate_() as HTMLInputElement;

    // Set the accessibility state
    if (this.min_ > -Infinity) {
      htmlInput.min = `${this.min_}`;
      aria.setState(htmlInput, aria.State.VALUEMIN, this.min_);
    }
    if (this.max_ < Infinity) {
      htmlInput.max = `${this.max_}`;
      aria.setState(htmlInput, aria.State.VALUEMAX, this.max_);
    }
    return htmlInput;
  }

  /**
   * Initialize the field's DOM.
   *
   * @override
   */

  public override initView() {
    super.initView();
    if (this.fieldGroup_) {
      dom.addClass(this.fieldGroup_, 'blocklyNumberField');
    }
  }

  /**
   * Construct a FieldNumber from a JSON arg object.
   *
   * @param options A JSON object with options (value, min, max, and precision).
   * @returns The new field instance.
   * @nocollapse
   * @internal
   */
  static override fromJson(options: FieldNumberFromJsonConfig): FieldNumber {
    // `this` might be a subclass of FieldNumber if that class doesn't override
    // the static fromJson method.
    return new this(
      options.value,
      undefined,
      undefined,
      undefined,
      undefined,
      options,
    );
  }
}

fieldRegistry.register('field_number', FieldNumber);

FieldNumber.prototype.DEFAULT_VALUE = 0;

/**
 * Config options for the number field.
 */
export interface FieldNumberConfig extends FieldInputConfig {
  min?: number;
  max?: number;
  precision?: number;
}

/**
 * fromJson config options for the number field.
 */
export interface FieldNumberFromJsonConfig extends FieldNumberConfig {
  value?: number;
}

/**
 * A function that is called to validate changes to the field's value before
 * they are set.
 *
 * @see {@link https://developers.google.com/blockly/guides/create-custom-blocks/fields/validators#return_values}
 * @param newValue The value to be validated.
 * @returns One of three instructions for setting the new value: `T`, `null`,
 * or `undefined`.
 *
 * - `T` to set this function's returned value instead of `newValue`.
 *
 * - `null` to invoke `doValueInvalid_` and not set a value.
 *
 * - `undefined` to set `newValue` as is.
 */
export type FieldNumberValidator = FieldInputValidator<number>;