// TODO: this file is located in the client src folder because
// otherwise, Create React App will refuse to compile it.
// Putting it in the server folder or in its own folder makes more sense.

// This file represents the API interface for Mudbase's back-end.
// Each endpoint is described by its endpoint address,
// a request structure, a response structure and
// a checking function which determines request validity.

// Query for songs (POST).
export const QuerySongsEndpoint = '/song/query';
export enum SongQueryElemOp {
    And = "AND",
    Or = "OR",
}
export enum SongQueryFilterOp {
    Eq = "EQ",
    Ne = "NE",
    In = "IN",
    NotIn = "NOTIN"
}
export enum SongQueryElemProperty {
    id = "id",
    artistIds = "artistIds",
    albumIds = "albumIds",
}
export interface SongQueryElem {
    prop?: SongQueryElemProperty,
    propOperand?: any,
    propOperator?: SongQueryFilterOp,
    children?: SongQueryElem[]
    childrenOperator?: SongQueryElemOp,
}
export interface SongQuery extends SongQueryElem {}
export interface QuerySongsRequest {
    query: SongQuery
}
export interface QuerySongsResponse {
    ids: Number[]
}
export function checkQuerySongsElem(elem:any): boolean {
    if(elem.childrenOperator && elem.children) {
        elem.children.forEach((child:any) => {
            if(!checkQuerySongsElem(child)) {
                return false;
            }
        });
    }
    return (elem.childrenOperator && elem.children) ||
    (elem.prop && elem.propOperand && elem.propOperator) ||
    Object.keys(elem).length == 0;
}
export function checkQuerySongsRequest(req:any): boolean {
    return "query" in req && checkQuerySongsElem(req.query);
}

// Get song details (GET).
export const SongDetailsEndpoint = '/song/:id';
export interface SongDetailsRequest {}
export interface SongDetailsResponse {
    title: String,
    storeLinks: String[],
    artistIds: Number[],
    albumIds: Number[],
}
export function checkSongDetailsRequest(req:any): boolean {
    return true;
}

// Query for artists.
export const QueryArtistsEndpoint = '/artist/query';
export interface QueryArtistsRequest {}
export interface QueryArtistsResponse {
    ids: Number[]
}
export function checkQueryArtistsRequest(req:any): boolean {
    return true;
}

// Get artist details (GET).
export const ArtistDetailsEndpoint = '/artist/:id';
export interface ArtistDetailsRequest {}
export interface ArtistDetailsResponse {
    name: String,
    storeLinks: String[],
}
export function checkArtistDetailsRequest(req:any): boolean {
    return true;
}

// Create a new song (POST).
export const CreateSongEndpoint = '/song';
export interface CreateSongRequest {
    title: String;
    artistIds?: Number[];
    albumIds?: Number[];
    storeLinks?: String[];
}
export interface CreateSongResponse {
    id: Number;
}
export function checkCreateSongRequest(req:any): boolean {
    return "body" in req &&
    "title" in req.body;
}

// Modify an existing song (PUT).
export const ModifySongEndpoint = '/song/:id';
export interface ModifySongRequest {
    title?: String;
    artistIds?: Number[];
    albumIds?: Number[];
    storeLinks?: String[];
}
export interface ModifySongResponse {}
export function checkModifySongRequest(req:any): boolean {
    return true;
}

// Create a new artist (POST).
export const CreateArtistEndpoint = '/artist';
export interface CreateArtistRequest {
    name: String;
    songIds?: Number[];
    albumIds?: Number[];
    storeLinks?: String[];
}
export interface CreateArtistResponse {
    id: Number;
}
export function checkCreateArtistRequest(req:any): boolean {
    return "body" in req &&
    "name" in req.body;
}

// Modify an existing artist (PUT).
export const ModifyArtistEndpoint = '/artist/:id';
export interface ModifyArtistRequest {
    name?: String,
    storeLinks?: String[],
}
export interface ModifyArtistResponse {}
export function checkModifyArtistRequest(req:any): boolean {
    return true;
}

// Create a new tag (POST).
export const CreateTagEndpoint = '/tag';
export interface CreateTagRequest {
    name: String;
    parentId?: Number;
}
export interface CreateTagResponse {
    id: Number;
}
export function checkCreateTagRequest(req:any): boolean {
    return "body" in req &&
    "name" in req.body;
}

// Modify an existing tag (PUT).
export const ModifyTagEndpoint = '/tag/:id';
export interface ModifyTagRequest {
    name?: String,
    parentId?: Number;
}
export interface ModifyTagResponse {}
export function checkModifyTagRequest(req:any): boolean {
    return true;
}

// Query for tags.
export const QueryTagEndpoint = '/tag/query';
export interface QueryTagsRequest {}
export interface QueryTagsResponse {
    ids: Number[]
}
export function checkQueryTagsRequest(req:any): boolean {
    return true;
}

// Get tag details (GET).
export const TagDetailsEndpoint = '/tag/:id';
export interface TagDetailsRequest {}
export interface TagDetailsResponse {
    name: String,
    parentId?: Number,
}
export function checkTagDetailsRequest(req:any): boolean {
    return true;
}