import { ComponentType } from "react";
import {
    CacheConfig,
    ConcreteRequest,
    DisposeFn,
    FetchPolicy,
    GraphQLResponse,
    IEnvironment,
    Observable,
    OperationType,
    PreloadableConcreteRequest,
    VariablesOf,
} from "relay-runtime";
import { GetEntryPointComponentFromEntryPoint, GetEntryPointParamsFromEntryPoint } from "./helpers";

export { VariablesOf } from "relay-runtime";

export interface JSResourceReference<TModule> {
    getModuleId(): string;

    getModuleIfRequired(): TModule | null;

    load(): Promise<TModule>;
}

export type PreloadFetchPolicy = "store-or-network" | "store-and-network" | "network-only";

export type PreloadOptions = Readonly<{
    fetchKey?: string | number | undefined;
    fetchPolicy?: PreloadFetchPolicy | null | undefined;
    networkCacheConfig?: CacheConfig | null | undefined;
}>;

export type LoadQueryOptions = Readonly<{
    fetchPolicy?: FetchPolicy | null | undefined;
    networkCacheConfig?: CacheConfig | null | undefined;
    onQueryAstLoadTimeout?: (() => void) | null | undefined;
}>;

export type EnvironmentProviderOptions<T extends Record<string, unknown> = Record<string, unknown>> = T;

export interface PreloadedQuery<
    TQuery extends OperationType,
    TEnvironmentProviderOptions = EnvironmentProviderOptions,
> extends
    Readonly<{
        kind: "PreloadedQuery";
        environment: IEnvironment;
        environmentProviderOptions?: TEnvironmentProviderOptions | null | undefined;
        fetchKey: string | number;
        fetchPolicy: PreloadFetchPolicy;
        networkCacheConfig?: CacheConfig | null | undefined;
        id?: string | null | undefined;
        name: string;
        source?: Observable<GraphQLResponse> | null | undefined;
        variables: VariablesOf<TQuery>;
        dispose: DisposeFn;
        isDisposed: boolean;
    }>
{}

export type PreloadQueryStatus = Readonly<{
    cacheConfig?: CacheConfig | null | undefined;
    source: "cache" | "network";
    fetchTime?: number | null | undefined;
}>;

/**
 * The Interface of the EntryPoints .entrypoint files
 *
 * Every .entrypoint file it's an object that must have two required fields:
 * - getPreloadProps(...)  function that will return the description of preloaded
 *   queries and preloaded (nested) entry points for the current entry point
 * - root - JSResource of the module that will render those preloaded queries
 *
 * TEntryPointParams - object that contains all necessary information to execute
 * the preloaders (routeParams, query variables)
 *
 * TPreloadedQueries -  queries, defined in the root components
 *
 * TNestedEntryPoints - nested entry points, defined in the root components
 *
 * TRuntimeProps - the type of additional props that you may pass to the
 * component (like `onClick` handler, etc) during runtime. Values for them
 * defined during component runtime
 *
 * TExtraProps - a bag of extra props that you may define in `entrypoint` file
 * and they will be passed to the EntryPointComponent as `extraProps`
 */
interface InternalEntryPointRepresentation<
    /**
     * object that contains all necessary information to execute the preloaders (routeParams, query variables)
     */
    TEntryPointParams extends {},
    /**
     * queries, defined in the root components
     */
    TPreloadedQueries extends Record<string, OperationType>,
    /**
     * nested entry points, defined in the root components
     */
    TNestedEntryPoints extends {},
    /**
     * the type of additional props that you may pass to the component (like `onClick` handler, etc) during runtime.
     * Values for them defined during component runtime
     */
    TRuntimeProps extends {},
    /**
     * a bag of extra props that you may define in `entrypoint` file and they will be passed to the EntryPointComponent
     * as `extraProps`
     */
    TExtraProps extends {} | null,
> extends
    Readonly<{
        root: JSResourceReference<
            EntryPointComponent<TPreloadedQueries, TNestedEntryPoints, TRuntimeProps, TExtraProps>
        >;
        getPreloadProps: (
            entryPointParams: TEntryPointParams,
        ) => PreloadProps<TEntryPointParams, TPreloadedQueries, TNestedEntryPoints, TExtraProps>;
    }>
{}

type ThinQueryParamsObject<TPreloadedQueries extends Record<string, OperationType> = {}> = {
    [K in keyof TPreloadedQueries]: ThinQueryParams<TPreloadedQueries[K]>;
};

type ThinNestedEntryPointParamsObject<
    TEntryPoints extends Record<string, EntryPoint<any, any> | undefined> = {},
> = {
    [K in keyof TEntryPoints]: ThinNestedEntryPointParams<TEntryPoints[K]>;
};

type PreloadedQueries<TPreloadedQueries> = TPreloadedQueries extends Record<string, OperationType> ? {
        [T in keyof TPreloadedQueries]: PreloadedQuery<TPreloadedQueries[T]>;
    }
    : never;

type PreloadedEntryPoints<TEntryPoints> = TEntryPoints extends Record<
    string,
    InternalEntryPointRepresentation<any, any, any, any, any> | undefined
> ? {
        [T in keyof TEntryPoints]: PreloadedEntryPoint<
            GetEntryPointComponentFromEntryPoint<TEntryPoints[T]>
        >;
    }
    : never;

// Return type of the `getPreloadProps(...)` of the entry point
export interface PreloadProps<
    TPreloadParams extends {},
    TPreloadedQueries extends Record<string, OperationType>,
    TNestedEntryPoints extends Record<string, EntryPoint<any, any> | undefined>,
    TExtraProps extends {} | null,
> extends
    Readonly<{
        entryPoints?: ThinNestedEntryPointParamsObject<TNestedEntryPoints> | undefined;
        extraProps?: TExtraProps | undefined;
        queries?: ThinQueryParamsObject<TPreloadedQueries> | undefined;
    }>
{}

// The shape of the props of the entry point `root` component
export interface EntryPointProps<TPreloadedQueries, TNestedEntryPoints, TRuntimeProps, TExtraProps> extends
    Readonly<{
        entryPoints: PreloadedEntryPoints<TNestedEntryPoints>;
        extraProps: TExtraProps;
        props: TRuntimeProps;
        queries: PreloadedQueries<TPreloadedQueries>;
    }>
{}

// Type of the entry point `root` component
export type EntryPointComponent<
    TPreloadedQueries extends Record<string, OperationType>,
    TNestedEntryPoints extends Record<string, EntryPoint<any, any> | undefined>,
    TRuntimeProps extends {} = {},
    TExtraProps extends {} | null = {},
> = ComponentType<EntryPointProps<TPreloadedQueries, TNestedEntryPoints, TRuntimeProps, TExtraProps>>;

// Return type of `loadEntryPoint(...)`
export type PreloadedEntryPoint<TEntryPointComponent> = TEntryPointComponent extends EntryPointComponent<
    infer TPreloadedQueries,
    infer TNestedEntryPoints,
    infer TRuntimeProps,
    infer TExtraProps
> ? Readonly<{
        dispose: DisposeFn;
        entryPoints: PreloadedEntryPoints<TNestedEntryPoints>;
        extraProps: TExtraProps;
        getComponent: () => TEntryPointComponent;
        isDisposed: boolean;
        queries: PreloadedQueries<TPreloadedQueries>;
        rootModuleID: string;
    }>
    : never;

export interface ThinQueryParams<
    TQuery extends OperationType,
    TEnvironmentProviderOptions extends EnvironmentProviderOptions = EnvironmentProviderOptions,
> extends
    Readonly<{
        /**
         * A reference to the $Parameters file that matches the type param provided to preloadQuery type.
         *
         * NOTE: For now, since OSS relay-compiler doesnt support generating the $Parameters file, you must give the query
         * wou would have given to usePreloadedQuery
         */
        parameters: ConcreteRequest | PreloadableConcreteRequest<TQuery>;
        /**
         * Variables to give to the query
         */
        variables: VariablesOf<TQuery>;
        /**
         * Any execution options to apply during network
         */
        options?: PreloadOptions | null | undefined;
        environmentProviderOptions?: TEnvironmentProviderOptions | null | undefined;
    }>
{}

export interface ThinNestedEntryPointParams<TEntryPoint> extends
    Readonly<{
        entryPoint: TEntryPoint;
        entryPointParams: GetEntryPointParamsFromEntryPoint<TEntryPoint>;
    }>
{}

export type EntryPoint<TEntryPointComponent, TEntryPointParams extends {} = {}> = InternalEntryPointRepresentation<
    TEntryPointParams,
    TEntryPointComponent extends EntryPointComponent<infer TPreloadedQueries, any, any, any> ? TPreloadedQueries
        : never,
    TEntryPointComponent extends EntryPointComponent<any, infer TNestedEntryPoints, any, any> ? TNestedEntryPoints
        : never,
    TEntryPointComponent extends EntryPointComponent<any, any, infer TRuntimeProps, any> ? TRuntimeProps : never,
    TEntryPointComponent extends EntryPointComponent<any, any, any, infer TExtraProps> ? TExtraProps : never
>;

// eslint-disable-next-line @typescript-eslint/naming-convention
export interface IEnvironmentProvider<TOptions> {
    getEnvironment(options: TOptions | null): IEnvironment;
}