import * as React from 'react';
import { PropInjector } from '@material-ui/types';
import * as CSS from 'csstype';
import * as JSS from 'jss';
import { DefaultTheme } from '../defaultTheme';

// Disable automatic export
export {};

type JSSFontface = CSS.FontFace & { fallbacks?: CSS.FontFace[] };

type PropsFunc<Props extends object, T> = (props: Props) => T;

/**
 * Allows the user to augment the properties available
 */
export interface BaseCSSProperties extends CSS.Properties<number | string> {
  '@font-face'?: JSSFontface | JSSFontface[];
}

export interface CSSProperties extends BaseCSSProperties {
  // Allow pseudo selectors and media queries
  // `unknown` is used since TS does not allow assigning an interface without
  // an index signature to one with an index signature. This is to allow type safe
  // module augmentation.
  // Technically we want any key not typed in `BaseCSSProperties` to be of type
  // `CSSProperties` but this doesn't work. The index signature needs to cover
  // BaseCSSProperties as well. Usually you would use `BaseCSSProperties[keyof BaseCSSProperties]`
  // but this would not allow assigning React.CSSProperties to CSSProperties
  [k: string]: unknown | CSSProperties;
}

export type BaseCreateCSSProperties<Props extends object = {}> = {
  [P in keyof BaseCSSProperties]: BaseCSSProperties[P] | PropsFunc<Props, BaseCSSProperties[P]>;
};

export interface CreateCSSProperties<Props extends object = {}>
  extends BaseCreateCSSProperties<Props> {
  // Allow pseudo selectors and media queries
  [k: string]:
    | BaseCreateCSSProperties<Props>[keyof BaseCreateCSSProperties<Props>]
    | CreateCSSProperties<Props>;
}

/**
 * This is basically the API of JSS. It defines a Map<string, CSS>,
 * where
 * - the `keys` are the class (names) that will be created
 * - the `values` are objects that represent CSS rules (`React.CSSProperties`).
 *
 * if only `CSSProperties` are matched `Props` are inferred to `any`
 */
export type StyleRules<Props extends object = {}, ClassKey extends string = string> = Record<
  ClassKey,
  // JSS property bag
  | CSSProperties
  // JSS property bag where values are based on props
  | CreateCSSProperties<Props>
  // JSS property bag based on props
  | PropsFunc<Props, CreateCSSProperties<Props>>
>;

/**
 * @internal
 */
export type StyleRulesCallback<Theme, Props extends object, ClassKey extends string = string> = (
  theme: Theme
) => StyleRules<Props, ClassKey>;

export type Styles<Theme, Props extends object, ClassKey extends string = string> =
  | StyleRules<Props, ClassKey>
  | StyleRulesCallback<Theme, Props, ClassKey>;

export interface WithStylesOptions<Theme = DefaultTheme> extends JSS.StyleSheetFactoryOptions {
  defaultTheme?: Theme;
  flip?: boolean;
  withTheme?: boolean;
  name?: string;
}

export type ClassNameMap<ClassKey extends string = string> = Record<ClassKey, string>;

/**
 * @internal
 */
export type ClassKeyInferable<Theme, Props extends object> = string | Styles<Theme, Props>;
export type ClassKeyOfStyles<StylesOrClassKey> = StylesOrClassKey extends string
  ? StylesOrClassKey
  : StylesOrClassKey extends StyleRulesCallback<any, any, infer ClassKey>
  ? ClassKey
  : StylesOrClassKey extends StyleRules<any, infer ClassKey>
  ? ClassKey
  : never;

/**
 * infers the type of the props used in the styles
 */
export type PropsOfStyles<StylesType> = StylesType extends Styles<any, infer Props> ? Props : {};

/**
 * infers the type of the theme used in the styles
 */
export type ThemeOfStyles<StylesType> = StylesType extends Styles<infer Theme, any> ? Theme : {};

export type WithStyles<
  StylesType extends ClassKeyInferable<any, any>,
  IncludeTheme extends boolean | undefined = false
> = (IncludeTheme extends true ? { theme: ThemeOfStyles<StylesType> } : {}) & {
  classes: ClassNameMap<ClassKeyOfStyles<StylesType>>;
  innerRef?: React.Ref<any>;
} & PropsOfStyles<StylesType>;

export interface StyledComponentProps<ClassKey extends string = string> {
  /**
   * Override or extend the styles applied to the component.
   */
  classes?: Partial<ClassNameMap<ClassKey>>;
  innerRef?: React.Ref<any>;
}

export default function withStyles<
  StylesType extends Styles<any, any>,
  Options extends WithStylesOptions<ThemeOfStyles<StylesType>> = {}
>(
  style: StylesType,
  options?: Options
): PropInjector<
  WithStyles<StylesType, Options['withTheme']>,
  StyledComponentProps<ClassKeyOfStyles<StylesType>> & PropsOfStyles<StylesType>
>;
