import {LegacyPluginThis} from './plugin_this';

/**
 * A synchronous callback that implements a custom Sass function. This can be
 * passed to [[LegacySharedOptions.functions]] for either [[render]] or
 * [[renderSync]].
 *
 * If this throws an error, Sass will treat that as the function failing with
 * that error message.
 *
 * ```js
 * const result = sass.renderSync({
 *   file: 'style.scss',
 *   functions: {
 *     "sum($arg1, $arg2)": (arg1, arg2) => {
 *       if (!(arg1 instanceof sass.types.Number)) {
 *         throw new Error("$arg1: Expected a number");
 *       } else if (!(arg2 instanceof sass.types.Number)) {
 *         throw new Error("$arg2: Expected a number");
 *       }
 *       return new sass.types.Number(arg1.getValue() + arg2.getValue());
 *     }
 *   }
 * });
 * ```
 *
 * @param args - One argument for each argument that's declared in the signature
 * that's passed to [[LegacySharedOptions.functions]]. If the signature [takes
 * arbitrary arguments](https://sass-lang.com/documentation/at-rules/function#taking-arbitrary-arguments),
 * they're passed as a single argument list in the last argument.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[CustomFunction]] with [[compile]], [[compileString]],
 * [[compileAsync]], and [[compileStringAsync]] instead.
 */
export type LegacySyncFunction = (
  this: LegacyPluginThis,
  ...args: LegacyValue[]
) => LegacyValue;

/**
 * An asynchronous callback that implements a custom Sass function. This can be
 * passed to [[LegacySharedOptions.functions]], but only for [[render]].
 *
 * An asynchronous function must return `undefined`. Its final argument will
 * always be a callback, which it should call with the result of the function
 * once it's done running.
 *
 * If this throws an error, Sass will treat that as the function failing with
 * that error message.
 *
 * ```js
 * sass.render({
 *   file: 'style.scss',
 *   functions: {
 *     "sum($arg1, $arg2)": (arg1, arg2, done) => {
 *       if (!(arg1 instanceof sass.types.Number)) {
 *         throw new Error("$arg1: Expected a number");
 *       } else if (!(arg2 instanceof sass.types.Number)) {
 *         throw new Error("$arg2: Expected a number");
 *       }
 *       done(new sass.types.Number(arg1.getValue() + arg2.getValue()));
 *     }
 *   }
 * }, (result, error) => {
 *   // ...
 * });
 * ```
 *
 * This is passed one argument for each argument that's declared in the
 * signature that's passed to [[LegacySharedOptions.functions]]. If the
 * signature [takes arbitrary
 * arguments](https://sass-lang.com/documentation/at-rules/function#taking-arbitrary-arguments),
 * they're passed as a single argument list in the last argument before the
 * callback.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[CustomFunction]] with [[compile]], [[compileString]],
 * [[compileAsync]], and [[compileStringAsync]] instead.
 */
export type LegacyAsyncFunction =
  | ((this: LegacyPluginThis, done: (result: LegacyValue) => void) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      arg2: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      arg2: LegacyValue,
      arg3: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      arg2: LegacyValue,
      arg3: LegacyValue,
      arg4: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      arg2: LegacyValue,
      arg3: LegacyValue,
      arg4: LegacyValue,
      arg5: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      arg1: LegacyValue,
      arg2: LegacyValue,
      arg3: LegacyValue,
      arg4: LegacyValue,
      arg5: LegacyValue,
      arg6: LegacyValue,
      done: LegacyAsyncFunctionDone
    ) => void)
  | ((
      this: LegacyPluginThis,
      ...args: [...LegacyValue[], LegacyAsyncFunctionDone]
    ) => void);

/**
 * The function called by a [[LegacyAsyncFunction]] to indicate that it's
 * finished.
 *
 * @param result - If this is a [[LegacyValue]], that indicates that the
 * function call completed successfully. If it's a [[types.Error]], that
 * indicates that the function call failed.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[CustomFunction]] with [[compile]], [[compileString]],
 * [[compileAsync]], and [[compileStringAsync]] instead.
 */
export type LegacyAsyncFunctionDone = (
  result: LegacyValue | types.Error
) => void;

/**
 * A callback that implements a custom Sass function. For [[renderSync]], this
 * must be a [[LegacySyncFunction]] which returns its result directly; for
 * [[render]], it may be either a [[LegacySyncFunction]] or a
 * [[LegacyAsyncFunction]] which calls a callback with its result.
 *
 * See [[LegacySharedOptions.functions]] for more details.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[CustomFunction]] with [[compile]], [[compileString]],
 * [[compileAsync]], and [[compileStringAsync]] instead.
 */
export type LegacyFunction<sync extends 'sync' | 'async'> = sync extends 'async'
  ? LegacySyncFunction | LegacyAsyncFunction
  : LegacySyncFunction;

/**
 * A type representing all the possible values that may be passed to or returned
 * from a [[LegacyFunction]].
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[Value]] with [[compile]], [[compileString]], [[compileAsync]],
 * and [[compileStringAsync]] instead.
 */
export type LegacyValue =
  | types.Null
  | types.Number
  | types.String
  | types.Boolean
  | types.Color
  | types.List
  | types.Map;

/**
 * A shorthand for `sass.types.Boolean.TRUE`.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[sassTrue]] with [[compile]], [[compileString]], [[compileAsync]],
 * and [[compileStringAsync]] instead.
 */
export const TRUE: types.Boolean<true>;

/**
 * A shorthand for `sass.types.Boolean.FALSE`.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[sassFalse]] with [[compile]], [[compileString]], [[compileAsync]],
 * and [[compileStringAsync]] instead.
 */
export const FALSE: types.Boolean<false>;

/**
 * A shorthand for `sass.types.Null.NULL`.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[sassNull]] with [[compile]], [[compileString]], [[compileAsync]],
 * and [[compileStringAsync]] instead.
 */
export const NULL: types.Null;

/**
 * The namespace for value types used in the legacy function API.
 *
 * @category Legacy
 * @deprecated This only works with the legacy [[render]] and [[renderSync]]
 * APIs. Use [[Value]] with [[compile]], [[compileString]], [[compileAsync]],
 * and [[compileStringAsync]] instead.
 */
export namespace types {
  /**
   * The class for Sass's singleton [`null`
   * value](https://sass-lang.com/documentation/values/null). The value itself
   * can be accessed through the [[NULL]] field.
   */
  export class Null {
    /** Sass's singleton `null` value. */
    static readonly NULL: Null;
  }

  /**
   * Sass's [number type](https://sass-lang.com/documentation/values/numbers).
   */
  export class Number {
    /**
     * @param value - The numeric value of the number.
     *
     * @param unit - If passed, the number's unit.
     *
     * Complex units can be represented as
     * `<unit>*<unit>*.../<unit>*<unit>*...`, with numerator units on the
     * left-hand side of the `/` and denominator units on the right. A number
     * with only numerator units may omit the `/` and the units after it, and a
     * number with only denominator units may be represented
     * with no units before the `/`.
     *
     * @example
     *
     * ```scss
     * new sass.types.Number(0.5); // == 0.5
     * new sass.types.Number(10, "px"); // == 10px
     * new sass.types.Number(10, "px*px"); // == 10px * 1px
     * new sass.types.Number(10, "px/s"); // == math.div(10px, 1s)
     * new sass.types.Number(10, "px*px/s*s"); // == 10px * math.div(math.div(1px, 1s), 1s)
     * ```
     */
    constructor(value: number, unit?: string);

    /**
     * Returns the value of the number, ignoring units.
     *
     * **Heads up!** This means that `96px` and `1in` will return different
     * values, even though they represent the same length.
     *
     * @example
     *
     * ```js
     * const number = new sass.types.Number(10, "px");
     * number.getValue(); // 10
     * ```
     */
    getValue(): number;

    /**
     * Destructively modifies this number by setting its numeric value to
     * `value`, independent of its units.
     *
     * @deprecated Use [[constructor]] instead.
     */
    setValue(value: number): void;

    /**
     * Returns a string representation of this number's units. Complex units are
     * returned in the same format that [[constructor]] accepts them.
     *
     * @example
     *
     * ```js
     * // number is `10px`.
     * number.getUnit(); // "px"
     *
     * // number is `math.div(10px, 1s)`.
     * number.getUnit(); // "px/s"
     * ```
     */
    getUnit(): string;

    /**
     * Destructively modifies this number by setting its units to `unit`,
     * independent of its numeric value. Complex units are specified in the same
     * format as [[constructor]].
     *
     * @deprecated Use [[constructor]] instead.
     */
    setUnit(unit: string): void;
  }

  /**
   * Sass's [string type](https://sass-lang.com/documentation/values/strings).
   *
   * **Heads up!** This API currently provides no way of distinguishing between
   * a [quoted](https://sass-lang.com/documentation/values/strings#quoted) and
   * [unquoted](https://sass-lang.com/documentation/values/strings#unquoted)
   * string.
   */
  export class String {
    /**
     * Creates an unquoted string with the given contents.
     *
     * **Heads up!** This API currently provides no way of creating a
     * [quoted](https://sass-lang.com/documentation/values/strings#quoted)
     * string.
     */
    constructor(value: string);

    /**
     * Returns the contents of the string. If the string contains escapes,
     * those escapes are included literally if it’s
     * [unquoted](https://sass-lang.com/documentation/values/strings#unquoted),
     * while the values of the escapes are included if it’s
     * [quoted](https://sass-lang.com/documentation/values/strings#quoted).
     *
     * @example
     *
     * ```
     * // string is `Arial`.
     * string.getValue(); // "Arial"
     *
     * // string is `"Helvetica Neue"`.
     * string.getValue(); // "Helvetica Neue"
     *
     * // string is `\1F46D`.
     * string.getValue(); // "\\1F46D"
     *
     * // string is `"\1F46D"`.
     * string.getValue(); // "👭"
     * ```
     */
    getValue(): string;

    /**
     * Destructively modifies this string by setting its numeric value to
     * `value`.
     *
     * **Heads up!** Even if the string was originally quoted, this will cause
     * it to become unquoted.
     *
     * @deprecated Use [[constructor]] instead.
     */
    setValue(value: string): void;
  }

  /**
   * Sass's [boolean type](https://sass-lang.com/documentation/values/booleans).
   *
   * Custom functions should respect Sass’s notion of
   * [truthiness](https://sass-lang.com/documentation/at-rules/control/if#truthiness-and-falsiness)
   * by treating `false` and `null` as falsey and everything else as truthy.
   *
   * **Heads up!** Boolean values can't be constructed, they can only be
   * accessed through the [[TRUE]] and [[FALSE]] constants.
   */
  export class Boolean<T extends boolean = boolean> {
    /**
     * Returns `true` if this is Sass's `true` value and `false` if this is
     * Sass's `false` value.
     *
     * @example
     *
     * ```js
     * // boolean is `true`.
     * boolean.getValue(); // true
     * boolean === sass.types.Boolean.TRUE; // true
     *
     * // boolean is `false`.
     * boolean.getValue(); // false
     * boolean === sass.types.Boolean.FALSE; // true
     * ```
     */
    getValue(): T;

    /** Sass's `true` value. */
    static readonly TRUE: Boolean<true>;

    /** Sass's `false` value. */
    static readonly FALSE: Boolean<false>;
  }

  /**
   * Sass's [color type](https://sass-lang.com/documentation/values/colors).
   */
  export class Color {
    /**
     * Creates a new Sass color with the given red, green, blue, and alpha
     * channels. The red, green, and blue channels must be integers between 0
     * and 255 (inclusive), and alpha must be between 0 and 1 (inclusive).
     *
     * @example
     *
     * ```js
     * new sass.types.Color(107, 113, 127); // #6b717f
     * new sass.types.Color(0, 0, 0, 0); // rgba(0, 0, 0, 0)
     * ```
     */
    constructor(r: number, g: number, b: number, a?: number);

    /**
     * Creates a new Sass color with alpha, red, green, and blue channels taken
     * from respective two-byte chunks of a hexidecimal number.
     *
     * @example
     *
     * ```js
     * new sass.types.Color(0xff6b717f); // #6b717f
     * new sass.types.Color(0x00000000); // rgba(0, 0, 0, 0)
     * ```
     */
    constructor(argb: number);

    /**
     * Returns the red channel of the color as an integer from 0 to 255.
     *
     * @example
     *
     * ```js
     * // color is `#6b717f`.
     * color.getR(); // 107
     *
     * // color is `#b37399`.
     * color.getR(); // 179
     * ```
     */
    getR(): number;

    /**
     * Sets the red channel of the color. The value must be an integer between 0
     * and 255 (inclusive).
     *
     * @deprecated Use [[constructor]] instead.
     */
    setR(value: number): void;

    /**
     * Returns the green channel of the color as an integer from 0 to 255.
     *
     * @example
     *
     * ```js
     * // color is `#6b717f`.
     * color.getG(); // 113
     *
     * // color is `#b37399`.
     * color.getG(); // 115
     * ```
     */
    getG(): number;

    /**
     * Sets the green channel of the color. The value must be an integer between
     * 0 and 255 (inclusive).
     *
     * @deprecated Use [[constructor]] instead.
     */
    setG(value: number): void;

    /**
     * Returns the blue channel of the color as an integer from 0 to 255.
     *
     * @example
     *
     * ```js
     * // color is `#6b717f`.
     * color.getB(); // 127
     *
     * // color is `#b37399`.
     * color.getB(); // 153
     * ```
     */
    getB(): number;

    /**
     * Sets the blue channel of the color. The value must be an integer between
     * 0 and 255 (inclusive).
     *
     * @deprecated Use [[constructor]] instead.
     */
    setB(value: number): void;

    /**
     * Returns the alpha channel of the color as a number from 0 to 1.
     *
     * @example
     *
     * ```js
     * // color is `#6b717f`.
     * color.getA(); // 1
     *
     * // color is `transparent`.
     * color.getA(); // 0
     * ```
     */
    getA(): number;

    /**
     * Sets the alpha channel of the color. The value must be between 0 and 1
     * (inclusive).
     *
     * @deprecated Use [[constructor]] instead.
     */
    setA(value: number): void;
  }

  /**
   * Sass's [list type](https://sass-lang.com/documentation/values/lists).
   *
   * **Heads up!** This list type’s methods use 0-based indexing, even though
   * within Sass lists use 1-based indexing. These methods also don’t support
   * using negative numbers to index backwards from the end of the list.
   */
  export class List {
    /**
     * Creates a new Sass list.
     *
     * **Heads up!** The initial values of the list elements are undefined.
     * These elements must be set using [[setValue]] before accessing them or
     * passing the list back to Sass.
     *
     * @example
     *
     * ```js
     * const list = new sass.types.List(3);
     * list.setValue(0, new sass.types.Number(10, "px"));
     * list.setValue(1, new sass.types.Number(15, "px"));
     * list.setValue(2, new sass.types.Number(32, "px"));
     * list; // 10px, 15px, 32px
     * ```
     *
     * @param length - The number of (initially undefined) elements in the list.
     * @param commaSeparator - If `true`, the list is comma-separated; otherwise,
     * it's space-separated. Defaults to `true`.
     */
    constructor(length: number, commaSeparator?: boolean);

    /**
     * Returns the element at `index`, or `undefined` if that value hasn't yet
     * been set.
     *
     * @example
     *
     * ```js
     * // list is `10px, 15px, 32px`
     * list.getValue(0); // 10px
     * list.getValue(2); // 32px
     * ```
     *
     * @param index - A (0-based) index into this list.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of elements in this list.
     */
    getValue(index: number): LegacyValue | undefined;

    /**
     * Sets the element at `index` to `value`.
     *
     * @example
     *
     * ```js
     * // list is `10px, 15px, 32px`
     * list.setValue(1, new sass.types.Number(18, "px"));
     * list; // 10px, 18px, 32px
     * ```
     *
     * @param index - A (0-based) index into this list.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of elements in this list.
     */
    setValue(index: number, value: LegacyValue): void;

    /**
     * Returns `true` if this list is comma-separated and `false` otherwise.
     *
     * @example
     *
     * ```js
     * // list is `10px, 15px, 32px`
     * list.getSeparator(); // true
     *
     * // list is `1px solid`
     * list.getSeparator(); // false
     * ```
     */
    getSeparator(): boolean;

    /**
     * Sets whether the list is comma-separated.
     *
     * @param isComma - `true` to make the list comma-separated, `false` otherwise.
     */
    setSeparator(isComma: boolean): void;

    /**
     * Returns the number of elements in the list.
     *
     * @example
     *
     * ```js
     * // list is `10px, 15px, 32px`
     * list.getLength(); // 3
     *
     * // list is `1px solid`
     * list.getLength(); // 2
     * ```
     */
    getLength(): number;
  }

  /**
   * Sass's [map type](https://sass-lang.com/documentation/values/maps).
   *
   * **Heads up!** This map type is represented as a list of key-value pairs
   * rather than a mapping from keys to values. The only way to find the value
   * associated with a given key is to iterate through the map checking for that
   * key. Maps created through this API are still forbidden from having duplicate
   * keys.
   */
  export class Map {
    /**
     * Creates a new Sass map.
     *
     * **Heads up!** The initial keys and values of the map are undefined. They
     * must be set using [[setKey]] and [[setValue]] before accessing them or
     * passing the map back to Sass.
     *
     * @example
     *
     * ```js
     * const map = new sass.types.Map(2);
     * map.setKey(0, new sass.types.String("width"));
     * map.setValue(0, new sass.types.Number(300, "px"));
     * map.setKey(1, new sass.types.String("height"));
     * map.setValue(1, new sass.types.Number(100, "px"));
     * map; // (width: 300px, height: 100px)
     * ```
     *
     * @param length - The number of (initially undefined) key/value pairs in the map.
     */
    constructor(length: number);

    /**
     * Returns the value in the key/value pair at `index`.
     *
     * @example
     *
     * ```js
     * // map is `(width: 300px, height: 100px)`
     * map.getValue(0); // 300px
     * map.getValue(1); // 100px
     * ```
     *
     * @param index -  A (0-based) index of a key/value pair in this map.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of pairs in this map.
     */
    getValue(index: number): LegacyValue;

    /**
     * Sets the value in the key/value pair at `index` to `value`.
     *
     * @example
     *
     * ```js
     * // map is `("light": 200, "medium": 400, "bold": 600)`
     * map.setValue(1, new sass.types.Number(300));
     * map; // ("light": 200, "medium": 300, "bold": 600)
     * ```
     *
     * @param index -  A (0-based) index of a key/value pair in this map.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of pairs in this map.
     */
    setValue(index: number, value: LegacyValue): void;

    /**
     * Returns the key in the key/value pair at `index`.
     *
     * @example
     *
     * ```js
     * // map is `(width: 300px, height: 100px)`
     * map.getKey(0); // width
     * map.getKey(1); // height
     * ```
     *
     * @param index -  A (0-based) index of a key/value pair in this map.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of pairs in this map.
     */
    getKey(index: number): LegacyValue;

    /**
     * Sets the value in the key/value pair at `index` to `value`.
     *
     * @example
     *
     * ```js
     * // map is `("light": 200, "medium": 400, "bold": 600)`
     * map.setValue(1, new sass.types.String("lighter"));
     * map; // ("lighter": 200, "medium": 300, "bold": 600)
     * ```
     *
     * @param index -  A (0-based) index of a key/value pair in this map.
     * @throws `Error` if `index` is less than 0 or greater than or equal to the
     * number of pairs in this map.
     */
    setKey(index: number, key: LegacyValue): void;

    /**
     * Returns the number of key/value pairs in this map.
     *
     * @example
     *
     * ```js
     * // map is `("light": 200, "medium": 400, "bold": 600)`
     * map.getLength(); // 3
     *
     * // map is `(width: 300px, height: 100px)`
     * map.getLength(); // 2
     * ```
     */
    getLength(): number;
  }

  /**
   * An error that can be returned from a Sass function to signal that it
   * encountered an error. This is the only way to signal an error
   * asynchronously from a [[LegacyAsyncFunction]].
   */
  export class Error {
    constructor(message: string);
  }
}