/**
 * @file API client for communicating with the Elysium backend.
 * @copyright nhcarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */
/* eslint-disable max-lines -- API client grows with each new endpoint group */
import type {
  AboutResponse,
  ApotheosisRequest,
  ApotheosisResponse,
  AuthResponse,
  AwakeningRequest,
  AwakeningResponse,
  BossChallengeRequest,
  BossChallengeResponse,
  BuyAwakeningUpgradeRequest,
  BuyAwakeningUpgradeResponse,
  BuyConsecrationUpgradeRequest,
  BuyConsecrationUpgradeResponse,
  BuyEchoUpgradeRequest,
  BuyEchoUpgradeResponse,
  BuyEnlightenmentUpgradeRequest,
  BuyEnlightenmentUpgradeResponse,
  BuyGoddessUpgradeRequest,
  BuyGoddessUpgradeResponse,
  BuyPrestigeUpgradeRequest,
  BuyPrestigeUpgradeResponse,
  BuySiringUpgradeRequest,
  BuySiringUpgradeResponse,
  BuyVampireUpgradeRequest,
  BuyVampireUpgradeResponse,
  ConsecrationRequest,
  ConsecrationResponse,
  CraftRecipeRequest,
  CraftRecipeResponse,
  EnlightenmentRequest,
  EnlightenmentResponse,
  ExploreClaimableResponse,
  ExploreCollectRequest,
  ExploreCollectResponse,
  ExploreStartRequest,
  ExploreStartResponse,
  ForceUnlocksResponse,
  GoddessBossChallengeRequest,
  GoddessBossChallengeResponse,
  GoddessCraftRequest,
  GoddessCraftResponse,
  GoddessExploreClaimableResponse,
  GoddessExploreCollectRequest,
  GoddessExploreCollectResponse,
  GoddessExploreStartRequest,
  GoddessExploreStartResponse,
  LoadResponse,
  PrestigeRequest,
  PrestigeResponse,
  PublicProfileResponse,
  SaveRequest,
  SaveResponse,
  SiringRequest,
  SiringResponse,
  SyncNewContentResponse,
  TranscendenceRequest,
  TranscendenceResponse,
  UpdateProfileRequest,
  UpdateProfileResponse,
  VampireBossChallengeRequest,
  VampireBossChallengeResponse,
  VampireCraftRequest,
  VampireCraftResponse,
  VampireExploreClaimableResponse,
  VampireExploreCollectRequest,
  VampireExploreCollectResponse,
  VampireExploreStartRequest,
  VampireExploreStartResponse,
} from "@elysium/types";

const baseUrl = "/api";

/**
 * Represents a 4xx API error so callers can distinguish expected server
 * rejections from unexpected failures. ValidationErrors are downgraded to
 * console.warn and are not forwarded to the error-email pipeline.
 */
class ValidationError extends Error {
  public readonly statusCode: number;

  /**
   * Creates a new ValidationError.
   * @param message - The error message from the server response.
   * @param statusCode - The HTTP status code (4xx) returned by the server.
   */
  public constructor(message: string, statusCode: number) {
    super(message);
    this.name = "ValidationError";
    this.statusCode = statusCode;
  }
}

const getToken = (): string | null => {
  return globalThis.localStorage.getItem("elysium_token");
};

/* eslint-disable @typescript-eslint/naming-convention -- HTTP header names require specific casing */
const buildHeaders = (): Record<string, string> => {
  const token = getToken();
  return {
    "Content-Type": "application/json",
    ...token !== null && token.length > 0
      ? { Authorization: `Bearer ${token}` }
      : {},
  };
};
/* eslint-enable @typescript-eslint/naming-convention -- HTTP header names require specific casing */

const fetchJson = async <T>(
  path: string,
  options?: RequestInit,
): Promise<T> => {
  const response = await fetch(`${baseUrl}${path}`, {
    ...options,
    headers: { ...buildHeaders(), ...options?.headers },
  });

  if (!response.ok) {
    /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- JSON error response requires type assertion */
    const errorBody = (await response.json().catch(() => {
      return { error: "Unknown error" };
    })) as Record<string, unknown>;
    const message
      = typeof errorBody.error === "string"
        ? errorBody.error
        : "Unknown error";
    if (response.status === 401) {
      globalThis.localStorage.removeItem("elysium_token");
      globalThis.localStorage.removeItem("elysium_save_signature");
      globalThis.location.href = "/";
    }
    if (response.status >= 400 && response.status < 500) {
      throw new ValidationError(message, response.status);
    }
    throw new Error(message);
  }

  /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- JSON response requires type assertion */
  return await (response.json() as Promise<T>);
};

/**
 * Fetches the about information from the API.
 * @returns The about response data.
 */
const getAbout = async(): Promise<AboutResponse> => {
  return await fetchJson<AboutResponse>("/about");
};

/**
 * Fetches the Discord OAuth URL from the API.
 * @returns The authentication URL string.
 */
const getAuthUrl = async(): Promise<string> => {
  const data = await fetchJson<{ url: string }>("/auth/url");
  return data.url;
};

/**
 * Handles the Discord OAuth callback and stores the auth token.
 * @param code - The OAuth authorization code from Discord.
 * @returns The authentication response data.
 */
const handleAuthCallback = async(code: string): Promise<AuthResponse> => {
  const data = await fetchJson<AuthResponse>(`/auth/callback?code=${code}`);
  globalThis.localStorage.setItem("elysium_token", data.token);
  return data;
};

/**
 * Loads the current game state from the server.
 * @returns The load response containing the game state.
 */
const loadGame = async(): Promise<LoadResponse> => {
  return await fetchJson<LoadResponse>("/game/load");
};

/**
 * Resets all game progress on the server.
 * @returns The load response after reset.
 */
const resetProgress = async(): Promise<LoadResponse> => {
  return await fetchJson<LoadResponse>("/game/reset", { method: "POST" });
};

/**
 * Saves the current game state to the server.
 * @param body - The save request payload containing the game state.
 * @returns The save response data.
 */
const saveGame = async(body: SaveRequest): Promise<SaveResponse> => {
  return await fetchJson<SaveResponse>("/game/save", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Challenges a boss with the current game state.
 * @param body - The boss challenge request payload.
 * @returns The boss challenge response data.
 */
const challengeBoss = async(
  body: BossChallengeRequest,
): Promise<BossChallengeResponse> => {
  return await fetchJson<BossChallengeResponse>("/boss/challenge", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Triggers a prestige reset on the server.
 * @param body - The prestige request payload.
 * @returns The prestige response data.
 */
const prestige = async(body: PrestigeRequest): Promise<PrestigeResponse> => {
  return await fetchJson<PrestigeResponse>("/prestige", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases a prestige upgrade on the server.
 * @param body - The buy prestige upgrade request payload.
 * @returns The buy prestige upgrade response data.
 */
const buyPrestigeUpgrade = async(
  body: BuyPrestigeUpgradeRequest,
): Promise<BuyPrestigeUpgradeResponse> => {
  return await fetchJson<BuyPrestigeUpgradeResponse>("/prestige/buy-upgrade", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Triggers a transcendence reset on the server.
 * @param body - The transcendence request payload.
 * @returns The transcendence response data.
 */
const transcend = async(
  body: TranscendenceRequest,
): Promise<TranscendenceResponse> => {
  return await fetchJson<TranscendenceResponse>("/transcendence", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases an echo upgrade on the server.
 * @param body - The buy echo upgrade request payload.
 * @returns The buy echo upgrade response data.
 */
const buyEchoUpgrade = async(
  body: BuyEchoUpgradeRequest,
): Promise<BuyEchoUpgradeResponse> => {
  return await fetchJson<BuyEchoUpgradeResponse>("/transcendence/buy-upgrade", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Triggers an apotheosis reset on the server.
 * @param body - The apotheosis request payload.
 * @returns The apotheosis response data.
 */
const achieveApotheosis = async(
  body: ApotheosisRequest,
): Promise<ApotheosisResponse> => {
  return await fetchJson<ApotheosisResponse>("/apotheosis", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Starts an exploration in a given area.
 * @param body - The exploration start request payload.
 * @returns The exploration start response data.
 */
const startExploration = async(
  body: ExploreStartRequest,
): Promise<ExploreStartResponse> => {
  return await fetchJson<ExploreStartResponse>("/explore/start", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Collects the rewards from a completed exploration.
 * @param body - The exploration collect request payload.
 * @returns The exploration collect response data.
 */
const collectExploration = async(
  body: ExploreCollectRequest,
): Promise<ExploreCollectResponse> => {
  return await fetchJson<ExploreCollectResponse>("/explore/collect", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Checks whether a given exploration area is ready to claim on the server.
 * @param areaId - The area ID to check.
 * @returns Whether the exploration is claimable.
 */
const checkExplorationClaimable = async(
  areaId: string,
): Promise<ExploreClaimableResponse> => {
  return await fetchJson<ExploreClaimableResponse>(
    `/explore/claimable?areaId=${encodeURIComponent(areaId)}`,
  );
};

/**
 * Crafts a recipe on the server.
 * @param body - The craft recipe request payload.
 * @returns The craft recipe response data.
 */
const craftRecipe = async(
  body: CraftRecipeRequest,
): Promise<CraftRecipeResponse> => {
  return await fetchJson<CraftRecipeResponse>("/craft", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Sends a request to fix any missing unlocks in the player's game state.
 * @returns The corrected game state and counts of what was unlocked.
 */
const forceUnlocks = async(): Promise<ForceUnlocksResponse> => {
  return await fetchJson<ForceUnlocksResponse>("/debug/force-unlocks", {
    method: "POST",
  });
};

/**
 * Syncs any content added after the player's save was created into their save.
 * @returns The updated game state and counts of what was added per content type.
 */
const syncNewContent = async(): Promise<SyncNewContentResponse> => {
  return await fetchJson<SyncNewContentResponse>("/debug/sync-new-content", {
    method: "POST",
  });
};

/**
 * Performs a complete hard reset of the player's game state via the debug endpoint.
 * @returns The fresh game state as a LoadResponse.
 */
const debugHardReset = async(): Promise<LoadResponse> => {
  return await fetchJson<LoadResponse>("/debug/hard-reset", { method: "POST" });
};

/**
 * Challenges a goddess boss.
 * @param body - The goddess boss challenge request payload.
 * @returns The goddess boss challenge response data.
 */
const challengeGoddessBoss = async(
  body: GoddessBossChallengeRequest,
): Promise<GoddessBossChallengeResponse> => {
  return await fetchJson<GoddessBossChallengeResponse>(
    "/goddess-boss/challenge",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Triggers a consecration reset on the server.
 * @param body - The consecration request payload.
 * @returns The consecration response data.
 */
const consecrate = async(
  body: ConsecrationRequest,
): Promise<ConsecrationResponse> => {
  return await fetchJson<ConsecrationResponse>("/consecration", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases a consecration upgrade on the server.
 * @param body - The buy consecration upgrade request payload.
 * @returns The buy consecration upgrade response data.
 */
const buyConsecrationUpgrade = async(
  body: BuyConsecrationUpgradeRequest,
): Promise<BuyConsecrationUpgradeResponse> => {
  return await fetchJson<BuyConsecrationUpgradeResponse>(
    "/consecration/buy-upgrade",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Triggers an enlightenment reset on the server.
 * @param body - The enlightenment request payload.
 * @returns The enlightenment response data.
 */
const enlighten = async(
  body: EnlightenmentRequest,
): Promise<EnlightenmentResponse> => {
  return await fetchJson<EnlightenmentResponse>("/enlightenment", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases an enlightenment upgrade on the server.
 * @param body - The buy enlightenment upgrade request payload.
 * @returns The buy enlightenment upgrade response data.
 */
const buyEnlightenmentUpgrade = async(
  body: BuyEnlightenmentUpgradeRequest,
): Promise<BuyEnlightenmentUpgradeResponse> => {
  return await fetchJson<BuyEnlightenmentUpgradeResponse>(
    "/enlightenment/buy-upgrade",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Purchases a goddess upgrade on the server.
 * @param body - The buy goddess upgrade request payload.
 * @returns The buy goddess upgrade response data.
 */
const buyGoddessUpgrade = async(
  body: BuyGoddessUpgradeRequest,
): Promise<BuyGoddessUpgradeResponse> => {
  return await fetchJson<BuyGoddessUpgradeResponse>("/goddess-upgrade/buy", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Crafts a goddess recipe on the server.
 * @param body - The goddess craft request payload.
 * @returns The goddess craft response data.
 */
const craftGoddessRecipe = async(
  body: GoddessCraftRequest,
): Promise<GoddessCraftResponse> => {
  return await fetchJson<GoddessCraftResponse>("/goddess-craft", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Starts a goddess exploration in a given area.
 * @param body - The goddess exploration start request payload.
 * @returns The goddess exploration start response data.
 */
const startGoddessExploration = async(
  body: GoddessExploreStartRequest,
): Promise<GoddessExploreStartResponse> => {
  return await fetchJson<GoddessExploreStartResponse>(
    "/goddess-explore/start",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Collects the rewards from a completed goddess exploration.
 * @param body - The goddess exploration collect request payload.
 * @returns The goddess exploration collect response data.
 */
const collectGoddessExploration = async(
  body: GoddessExploreCollectRequest,
): Promise<GoddessExploreCollectResponse> => {
  return await fetchJson<GoddessExploreCollectResponse>(
    "/goddess-explore/collect",
    { body: JSON.stringify(body), method: "PUT" },
  );
};

/**
 * Checks whether a given goddess exploration area is ready to claim on the server.
 * @param areaId - The area ID to check.
 * @returns Whether the goddess exploration is claimable.
 */
const checkGoddessExplorationClaimable = async(
  areaId: string,
): Promise<GoddessExploreClaimableResponse> => {
  return await fetchJson<GoddessExploreClaimableResponse>(
    `/goddess-explore/claimable?areaId=${encodeURIComponent(areaId)}`,
  );
};

/**
 * Challenges a vampire boss.
 * @param body - The vampire boss challenge request payload.
 * @returns The vampire boss challenge response data.
 */
const challengeVampireBoss = async(
  body: VampireBossChallengeRequest,
): Promise<VampireBossChallengeResponse> => {
  return await fetchJson<VampireBossChallengeResponse>(
    "/vampire-boss/challenge",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Triggers a siring reset on the server.
 * @param body - The siring request payload.
 * @returns The siring response data.
 */
const sire = async(body: SiringRequest): Promise<SiringResponse> => {
  return await fetchJson<SiringResponse>("/siring", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases a siring upgrade on the server.
 * @param body - The buy siring upgrade request payload.
 * @returns The buy siring upgrade response data.
 */
const buySiringUpgrade = async(
  body: BuySiringUpgradeRequest,
): Promise<BuySiringUpgradeResponse> => {
  return await fetchJson<BuySiringUpgradeResponse>("/siring/buy-upgrade", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Triggers a vampire awakening reset on the server.
 * @param body - The awakening request payload.
 * @returns The awakening response data.
 */
const awaken = async(body: AwakeningRequest): Promise<AwakeningResponse> => {
  return await fetchJson<AwakeningResponse>("/vampire-awakening", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Purchases a vampire awakening upgrade on the server.
 * @param body - The buy awakening upgrade request payload.
 * @returns The buy awakening upgrade response data.
 */
const buyAwakeningUpgrade = async(
  body: BuyAwakeningUpgradeRequest,
): Promise<BuyAwakeningUpgradeResponse> => {
  return await fetchJson<BuyAwakeningUpgradeResponse>(
    "/vampire-awakening/buy-upgrade",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Purchases a vampire upgrade on the server.
 * @param body - The buy vampire upgrade request payload.
 * @returns The buy vampire upgrade response data.
 */
const buyVampireUpgrade = async(
  body: BuyVampireUpgradeRequest,
): Promise<BuyVampireUpgradeResponse> => {
  return await fetchJson<BuyVampireUpgradeResponse>("/vampire-upgrade/buy", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Crafts a vampire recipe on the server.
 * @param body - The vampire craft request payload.
 * @returns The vampire craft response data.
 */
const craftVampireRecipe = async(
  body: VampireCraftRequest,
): Promise<VampireCraftResponse> => {
  return await fetchJson<VampireCraftResponse>("/vampire-craft", {
    body:   JSON.stringify(body),
    method: "POST",
  });
};

/**
 * Starts a vampire exploration in a given area.
 * @param body - The vampire exploration start request payload.
 * @returns The vampire exploration start response data.
 */
const startVampireExploration = async(
  body: VampireExploreStartRequest,
): Promise<VampireExploreStartResponse> => {
  return await fetchJson<VampireExploreStartResponse>(
    "/vampire-explore/start",
    { body: JSON.stringify(body), method: "POST" },
  );
};

/**
 * Collects the rewards from a completed vampire exploration.
 * @param body - The vampire exploration collect request payload.
 * @returns The vampire exploration collect response data.
 */
const collectVampireExploration = async(
  body: VampireExploreCollectRequest,
): Promise<VampireExploreCollectResponse> => {
  return await fetchJson<VampireExploreCollectResponse>(
    "/vampire-explore/collect",
    { body: JSON.stringify(body), method: "PUT" },
  );
};

/**
 * Checks whether a given vampire exploration area is ready to claim on the server.
 * @param areaId - The area ID to check.
 * @returns Whether the vampire exploration is claimable.
 */
const checkVampireExplorationClaimable = async(
  areaId: string,
): Promise<VampireExploreClaimableResponse> => {
  return await fetchJson<VampireExploreClaimableResponse>(
    `/vampire-explore/claimable?areaId=${encodeURIComponent(areaId)}`,
  );
};

/**
 * Fetches a public player profile by Discord ID.
 * @param discordId - The Discord ID of the player to look up.
 * @returns The public profile response data.
 */
const getPublicProfile = async(
  discordId: string,
): Promise<PublicProfileResponse> => {
  return await fetchJson<PublicProfileResponse>(`/profile/${discordId}`);
};

/**
 * Updates the current player's profile.
 * @param body - The update profile request payload.
 * @returns The update profile response data.
 */
const updateProfile = async(
  body: UpdateProfileRequest,
): Promise<UpdateProfileResponse> => {
  return await fetchJson<UpdateProfileResponse>("/profile", {
    body:   JSON.stringify(body),
    method: "PUT",
  });
};

export {
  ValidationError,
  achieveApotheosis,
  awaken,
  buyAwakeningUpgrade,
  buyConsecrationUpgrade,
  buyEchoUpgrade,
  buyEnlightenmentUpgrade,
  buyGoddessUpgrade,
  buyPrestigeUpgrade,
  buySiringUpgrade,
  buyVampireUpgrade,
  challengeBoss,
  challengeGoddessBoss,
  challengeVampireBoss,
  checkExplorationClaimable,
  checkGoddessExplorationClaimable,
  checkVampireExplorationClaimable,
  collectExploration,
  collectGoddessExploration,
  collectVampireExploration,
  consecrate,
  craftGoddessRecipe,
  craftRecipe,
  craftVampireRecipe,
  debugHardReset,
  enlighten,
  forceUnlocks,
  syncNewContent,
  getAbout,
  getAuthUrl,
  getPublicProfile,
  handleAuthCallback,
  loadGame,
  prestige,
  resetProgress,
  saveGame,
  sire,
  startExploration,
  startGoddessExploration,
  startVampireExploration,
  transcend,
  updateProfile,
};