// utils/types.ts

import { ItemDefinition } from "cosmos";

export type Emit = (message: string) => void;

export interface Product extends ItemDefinition {
  id: string;
  category: string;
  name: string;
  quantity: number;
  price: number;
  clearance: boolean;
}

type JSONValue<T> =
  | T
  | string
  | number
  | boolean
  | null
  | JSONObject
  | JSONArray;
interface JSONObject {
  [key: string]: JSONValue<
    string | number | boolean | null | JSONObject | JSONArray
  >;
}
interface JSONArray extends
  Array<
    JSONValue<string | number | boolean | null | JSONObject | JSONArray>
  > {}

export function rollUpArray<T, R>(
  array: T[],
  initialValue: R,
  rollUpFn: (accumulator: R, currentItem: T) => R,
): R {
  return array.reduce(rollUpFn, initialValue);
}

export function jsonDiff<T>(
  target: JSONValue<T>,
  newChange: JSONValue<T>,
): JSONValue<T> | undefined {
  // If source is null or undefined, return undefined (no difference)
  if (newChange === null || newChange === undefined) return undefined;

  // If types don't match or primitives are different, return source

  // If both are objects, compare recursively
  if (typeof target === "object" && typeof newChange === "object") {
    if (Array.isArray(target) && Array.isArray(newChange)) {
      // If arrays, compare by index
      const diffArray: JSONArray = [];
      let hasDiff: boolean = false;
      // Compare existing elements
      const maxAlikeIndex = Math.min(target.length, newChange.length);
      for (let i = 0; i < maxAlikeIndex; i++) {
        if (
          typeof target !== typeof newChange ||
          (typeof target !== "object" && target !== newChange)
        ) {
          diffArray[i] = newChange[i];
          if (newChange[i]) {
            hasDiff = true;
          }
        } else {
          const diff = jsonDiff(target[i], newChange[i]);
          if (diff !== undefined) {
            diffArray[i] = diff;
            if (diff !== null && diff !== undefined) {
              hasDiff = true;
            }
          } else {
            diffArray[i] = null;
          }
        }
      }
      for (let i = maxAlikeIndex; i < newChange.length; i++) {
        //console.log("added to array ", JSON.stringify(newChange[i]));
        diffArray[i] = newChange[i];
      }

      // Add additional elements from source
      // for (let i = target.length; i < newChange.length; i++) {
      //   diffArray[i] = newChange[i];
      // }

      return hasDiff || target.length !== newChange.length ? diffArray : null;
    } else if (!Array.isArray(target) && !Array.isArray(newChange)) {
      // If objects, compare by key
      const result: JSONObject = {};
      let hasDiff = false;

      // console.log("key",newChange);
      for (const key in newChange) {
        if (Object.prototype.hasOwnProperty.call(newChange, key)) {
          const diff = jsonDiff(
            (target as JSONObject)[key],
            (newChange as JSONObject)[key],
          );
          if (diff !== undefined) {
            result[key] = diff;
            hasDiff = true;
          }
        }
      }
      return hasDiff ? result : undefined;
    }
  } else if (typeof target !== typeof newChange || target !== newChange) {
    return newChange;
  }

  // For identical primitives or matching types, return undefined (no difference)
  return undefined;
}

export function jsonMerge<T>(
  target: JSONValue<T>,
  newChange: JSONValue<T>,
): JSONValue<T> {
  // If source is null or undefined, return target
  if (newChange === null || newChange === undefined) return target;

  // If types don't match, overwrite with source
  if (typeof target !== typeof newChange) return newChange;

  // If both are objects, merge recursively
  if (typeof target === "object" && typeof newChange === "object") {
    if (Array.isArray(target) && Array.isArray(newChange)) {
      // If arrays, merge by index
      const mergedArray = target.map((item, index) =>
        index < newChange.length ? jsonMerge(item, newChange[index]) : item
      );

      // Add additional non-null elements from source
      for (let i = target.length; i < newChange.length; i++) {
        if (newChange[i] !== null && newChange[i] !== undefined) {
          mergedArray.push(newChange[i]);
        }
      }
      for (let i = newChange.length; i < target.length; i++) {
        mergedArray.pop();
      }

      return mergedArray as JSONArray;
    } else if (!Array.isArray(target) && !Array.isArray(newChange)) {
      // If objects, merge by key
      const result = { ...target as JSONObject };
      for (const key in newChange) {
        if (Object.prototype.hasOwnProperty.call(newChange, key)) {
          result[key] = jsonMerge(
            (target as JSONObject)[key],
            (newChange as JSONObject)[key],
          );
        }
      }
      return result;
    }
  }

  // For primitive types or mismatched types, return source
  return newChange;
}

export function cloneObjectExcept<
  T extends object,
  K extends Extract<keyof T, string>,
>(
  obj: T,
  fieldToChange?: K[],
  changeObjects?: any[],
): T {
  if (Array.isArray(obj)) {
    const result = [];

    for (let i = 0; i < obj.length; ++i) {
      const item = obj[i];
      if (item && typeof item === "object") {
        result.push(cloneObjectExcept(item));
      } else {
        result.push(item);
      }
    }

    return result as T;
  } else {
    const result = {} as T;

    for (const key in obj) {
      if (
        fieldToChange === undefined ||
        !fieldToChange.some((changeKey) => changeKey === key)
      ) {
        const objValue = obj[key];
        if (
          Object.prototype.hasOwnProperty.call(obj, key) &&
          typeof objValue === "object"
        ) {
          result[key] = cloneObjectExcept(
            objValue as T[Extract<keyof T, string>] & object,
          );
        } else {
          result[key] = objValue;
        }
      }
    }

    if (fieldToChange && changeObjects) {
      for (let i = 0; i < fieldToChange.length; ++i) {
        result[fieldToChange[i]] = changeObjects[i];
      }
    }

    return result;
  }
}

export interface KvObj<T> {
  key: string[];
  value: T | null | undefined;
  ok: boolean;
  versionstamp: string;
}

export interface BlobObject {
  obj_key: string;
  any_value: string;
}

export interface SessionConfig {
  device_id: string;
  user_id: string;
  other_data: string;
  active_date: number;
  quiz_configs: Array<Array<string>>;
  active_route: string;
  page_data: string;
  active_quiz_index: number;
  active_question_index: number;
}

export interface QuizConfig {
  quiz_config_id: string;
  quiz_name: string;
  owner_id: string;
  quiz_mode: string;
  active_date: number;
  tab_name?: string;
  tab_index?: number;
  list_index?: number;
  questions: Array<{
    id: string;
    question_index?: number;
    quiz_id: string;
    owner_id: string;
    language_1: string;
    language_2: string;
    text_1: string;
    audio_file_1: string;
    text_2: string;
    audio_file_2: string;
    order_num: number;
    background_file: string;
    background_image_data: string;
    video_file: string;
    video_file_data: string;
  }>;
  results: Array<{
    success: boolean;
    total_time: number;
    help_count: number;
  }>;
}

export interface AudioFile {
  text: string;
  audio_file: string;
}

export interface ImageFile {
  image_text: string;
  image_file: string;
  image_data: string;
}

// Brain Study (Spaced Repetition) Types
export interface BrainQuestionProgress {
  id: string; // composite: `${user_id}_${question_id}` (mode-agnostic)
  user_id: string;
  quiz_id: string;
  question_id: string;
  current_mode: string; // Current mode in progression (e.g., "photo-see-bisaya")
  mode_index: number; // Index in QUIZ_MODES array (0-5)
  attempts: number;
  first_try_successes: number;
  consecutive_first_try: number; // Streak of first-try correct in current mode
  last_result: boolean | null; // true = correct on first try
  next_due_at: number; // timestamp for spaced repetition
  interval_days: number; // current spacing interval
  ease_factor: number; // SM-2 algorithm factor
  is_review_only: boolean; // Card has mastered all modes, only appears rarely
  created_on: number;
  updated_on: number;
}

export interface BrainStudyConfig {
  user_id: string;
  active_mode: string;
  queue: BrainQueueItem[];
  session_stats: {
    total_reviewed: number;
    correct_first_try: number;
    session_start: number;
  };
}

export interface BrainQueueItem {
  question_id: string;
  quiz_id: string;
  question_data: QuizConfig["questions"][0];
  progress: BrainQuestionProgress | null;
  is_new: boolean;
  display_mode: string; // The mode to display this card in (from progression)
  mode_index: number; // Index in QUIZ_MODES array (for sorting)
  is_review_only: boolean; // Whether this card is in review-only state
  // For active set tracking (client-side session state)
  has_been_retired?: boolean; // Set by client when card passes final mode
}