import type {AdUnitCode, BidderCode, ContextIdentifiers, Size} from "./types/common.d.ts";
import type {ORTBImp} from "./types/ortb/request.d.ts";
import type {Bid} from "./bidfactory.ts";
import type {MediaTypes} from "./mediaTypes.ts";
import type {DeepPartial} from "./types/objects.d.ts";

export interface RendererConfig {
  /**
   * URL to the renderer script that will be loaded before invoking `render`.
   */
  url?: string

  /**
   * Function that tells Prebid.js how to invoke the renderer script to render a bid.
   */
  render(bid: Bid): void;

  /**
   * if set to true, this renderer config will be used only when the bid adapter doesn't provide its own renderer.
   */
  backupOnly?: boolean;
}

// eslint-disable-next-line @typescript-eslint/no-empty-object-type
export interface BidderParams {
  /**
   * Adapter-specific parameters - to be extended in the adapters
   */
}

export interface BaseAdUnitBidDefinition {
  /**
   * Used for conditional ads (sizeMapping or sizeMappingV2 modules).
   */
  labelAny?: string[];
  /**
   * Used for conditional ads (sizeMapping or sizeMappingV2 modules).
   */
  labelAll?: string[];
  /**
   * Custom renderer. Takes precedence over adUnit.renderer, but applies only to this bidder or module.
   */
  renderer?: RendererConfig;
  /**
   * OpenRTB first-party data specific to this bidder or module. This is merged with, and takes precedence over, adUnit.ortb2Imp.
   */
  ortb2Imp?: DeepPartial<ORTBImp>;
}

export interface AdUnitBidderBid<BIDDER extends BidderCode> extends BaseAdUnitBidDefinition {
  /**
   * Unique code identifying the bidder.
   */
  bidder: BIDDER;
  module?: undefined | null;
  /**
   * Bid request parameters for a given bidder.
   */
  params: BIDDER extends keyof BidderParams ? BidderParams[BIDDER] : Record<string, unknown>;
  /**
   * One or more s2sConfig.name. If provided, this bid will be requested only from the given S2S instance(s).
   */
  s2sConfigName?: string | string[]
}

export type AdUnitModuleBidder = 'pbsBidAdapter';

export interface AdUnitModuleBid extends BaseAdUnitBidDefinition {
  /**
   * Module code - for requesting bids from modules that are not bid adapters
   */
  module: AdUnitModuleBidder;
  bidder?: never;
  params?: {
    /**
     * Name given to a PBS configuration. Used to identify specific PBS instances when multiple are in use.
     */
    configName?: string;
  }
}

export type AdUnitBidDefinition = AdUnitModuleBid | AdUnitBidderBid<keyof BidderParams> | AdUnitBidderBid<BidderCode>;

export interface AdUnitDefinition {
  /**
   * An identifier you create and assign to this ad unit.
   * Generally this is set to the ad slot name or the div element ID.
   * Used by setTargetingForGPTAsync() to match which auction is for which ad slot.
   */
  code: AdUnitCode;
  /**
   * Bid requests representing demand partners and associated parameters.
   */
  bids?: AdUnitBidDefinition[];
  mediaTypes?: MediaTypes;
  /**
   * TTL buffer override for this adUnit.
   */
  ttlBuffer?: number;
  /**
   * Used to signal OpenRTB Imp objects at the adUnit grain.
   * Similar to the global ortb2 field used for global first party data configuration, but specific to this adunit.
   */
  ortb2Imp?: DeepPartial<ORTBImp>;
  /**
   * Custom renderer, typically used for outstream video
   */
  renderer?: RendererConfig;

  /**
   * Used to flag adUnits as being separately billable. This allows for a publisher to trigger billing manually for winning bids. See pbjs.triggerBilling and onBidBillable for more info.
   */
  deferBilling?: boolean;
  /**
   * @deprecated - use mediaType specific size parameters instead.
   */
  sizes?: Size | Size[];
}

/**
 * Ad unit objects generated by Prebid (as opposed to the definitions provided by the publisher)
 * can have a placeholder "null" bidder to represent s2s-only stored requests.
 */
interface NullBid extends BaseAdUnitBidDefinition {
  bidder: null
  module?: undefined | null;
  params?: undefined | null;
}

export type AdUnitBid = AdUnitBidDefinition | NullBid;

export interface AdUnit extends ContextIdentifiers, Omit<AdUnitDefinition, 'bids'> {
  bids: AdUnitBid[]
}

const REQUESTS = 'requests';
const WINS = 'wins';
const AUCTIONS = 'auctions';

let adUnits = {};
export function reset() {
  adUnits = {}
}

function ensureAdUnit(adunit, bidderCode?) {
  const adUnit = adUnits[adunit] = adUnits[adunit] || { bidders: {} };
  if (bidderCode) {
    adUnit.bidders[bidderCode] = adUnit.bidders[bidderCode] || {}
    return adUnit.bidders[bidderCode]
  }
  return adUnit;
}

type AdUnitCounter = (adUnit: AdUnitCode) => number;
type BidderCounter = (adUnit: AdUnitCode, bidderCode: BidderCode) => number;
type Counter<BY_BIDDER extends boolean> = BY_BIDDER extends true ? BidderCounter : AdUnitCounter;

function incrementer<BY_BIDDER extends boolean>(counter, byBidder: BY_BIDDER): Counter<BY_BIDDER> {
  return function (adUnit, bidder?) {
    const counters = ensureAdUnit(adUnit, byBidder && bidder);
    counters[counter] = (counters[counter] ?? 0) + 1;
    return counters[counter];
  }
}

function getter<BY_BIDDER extends boolean>(counter, byBidder: BY_BIDDER): Counter<BY_BIDDER> {
  return function (adUnit, bidder?) {
    return ensureAdUnit(adUnit, byBidder && bidder)[counter] ?? 0;
  }
}

/**
 * Increments and returns current Adunit counter
 */
export const incrementRequestsCounter = incrementer(REQUESTS, false);

/**
 * Increments and returns current Adunit requests counter for a bidder
 */
export const incrementBidderRequestsCounter = incrementer(REQUESTS, true);

/**
 * Increments and returns current Adunit wins counter for a bidder
 */
export const incrementBidderWinsCounter = incrementer(WINS, true);

/**
 * Increments and returns current Adunit auctions counter
 */
export const incrementAuctionsCounter = incrementer(AUCTIONS, false);

/**
 * Returns current Adunit counter
 */
export const getRequestsCounter = getter(REQUESTS, false);

/**
 * Returns current Adunit requests counter for a specific bidder code
 */
export const getBidderRequestsCounter = getter(REQUESTS, true)

/**
 * Returns current Adunit requests counter for a specific bidder code
 */
export const getBidderWinsCounter = getter(WINS, true);

/**
 * Returns current Adunit auctions counter
 */
export const getAuctionsCounter = getter(AUCTIONS, false);