import { create } from "zustand";
import {
  MANASTORM_MAX_RESURRECTION_CHARGES,
  drawManastormStage,
  getManastormCatalog,
  manastormAffixes,
  manastormAvailableLoadoutIds,
  manastormCheckpointForLevel,
  manastormCacheChance,
  manastormGroupModifier,
  isManastormSpecialLevel,
  manastormMessage,
  manastormModeId,
  manastormReward,
  manastormRuntimeScaling,
  normalizeManastormPartySize,
  type ManastormEncounterDefinition,
  type ManastormPartySize,
  type ManastormRewardState,
  type ManastormRewardCacheState,
  type ManastormRunState,
} from "./manastorm";
import {
  createManastormClientOverlayState,
  withManastormNextWaveCountdown,
  withManastormSafetyBubble,
  type ManastormClientOverlayState,
  type ManastormSafetyBubbleUpdate,
} from "./manastormClientOverlay";
import {
  isManastormPortalCueId,
  manastormCueForStatusTransition,
  type ManastormClientCueRequest,
  type ManastormPortalCueId,
} from "./manastormClientCues";
import {
  resolveManastormActiveSpellLoadout,
  validateManastormActiveSpellLoadout,
  type ManastormActiveSpellLoadoutRequest,
} from "./manastormSpellLoadout";

export interface ManastormStartOptions {
  readonly partySize?: number;
  readonly startingLevel?: number;
  readonly unlockedThroughLevel?: number;
  readonly loadoutId?: string | null;
  readonly activeSpellLoadout?: ManastormActiveSpellLoadoutRequest;
  readonly modeId?: number;
  readonly cacheMeter?: number;
  readonly rewardCaches?: readonly ManastormRewardCacheState[];
  readonly random?: () => number;
}

export interface ManastormClientRuntimeFields {
  readonly clientOverlay: ManastormClientOverlayState;
  readonly clientCue: ManastormClientCueRequest | null;
  readonly clientCueRevision: number;
}

export interface ManastormState extends ManastormRunState, ManastormClientRuntimeFields {
  startRun: (
    randomOrOptions?: (() => number) | ManastormStartOptions,
  ) => ManastormEncounterDefinition;
  enterStage: () => boolean;
  observeTrash: (cleared: boolean) => void;
  observeBoss: (dead: boolean, looted: boolean, random?: () => number) => void;
  beginTransition: () => boolean;
  prepareNextEncounter: (random?: () => number) => ManastormEncounterDefinition | null;
  finishTransition: () => void;
  useResurrectionCharge: () => boolean;
  restartFromCheckpoint: (random?: () => number) => ManastormEncounterDefinition | null;
  setPartySize: (partySize: number) => boolean;
  setLoadout: (loadoutId: string | null) => boolean;
  setActiveSpellLoadout: (selectedIds: readonly string[]) => boolean;
  openRewardCache: (cacheId: string) => boolean;
  setNextWaveCountdown: (seconds: number | null) => void;
  setSafetyBubble: (update: ManastormSafetyBubbleUpdate) => void;
  requestClientCue: (cueId: ManastormPortalCueId) => boolean;
  clearClientCue: () => void;
  failRun: () => boolean;
  resetRun: () => void;
}

function safeMaximumLevel(): number {
  return Math.max(1, Math.trunc(getManastormCatalog().maximumLevel ?? 16_384));
}

function runtimeFields(
  level: number,
  partySize: ManastormPartySize,
  requestedLoadoutId?: string | null,
  requestedModeId?: number,
  unlockedThroughLevel = level,
) {
  const catalog = getManastormCatalog();
  const modeId = Math.trunc(requestedModeId ?? manastormModeId(catalog));
  const availableLoadoutIds = manastormAvailableLoadoutIds(level, partySize, catalog);
  const preferredLoadoutId = requestedLoadoutId === undefined
    ? catalog.defaultLoadoutId ?? null
    : requestedLoadoutId;
  const loadoutId = preferredLoadoutId && availableLoadoutIds.includes(preferredLoadoutId)
    ? preferredLoadoutId
    : availableLoadoutIds[0] ?? null;
  return {
    catalogId: catalog.id ?? "manastorm-catalog",
    modeId,
    groupModifier: manastormGroupModifier(partySize, catalog, modeId),
    scaling: manastormRuntimeScaling(level, partySize, catalog, modeId),
    activeAffixes: manastormAffixes(level, catalog, modeId, unlockedThroughLevel),
    availableLoadoutIds,
    loadoutId,
    message: manastormMessage(level, partySize, catalog, modeId),
  };
}

const initialRunState = (
  partySize: ManastormPartySize = 5,
  transitionRevision = 0,
): ManastormRunState & ManastormClientRuntimeFields => {
  const level = 1;
  const runtime = runtimeFields(level, partySize);
  return {
    status: "idle",
    phase: "idle",
    level,
    maximumLevel: safeMaximumLevel(),
    unlockedThroughLevel: 1,
    completed: 0,
    checkpointLevel: 1,
    milestone: false,
    partySize,
    maxResurrectionCharges: MANASTORM_MAX_RESURRECTION_CHARGES,
    resurrectionCharges: MANASTORM_MAX_RESURRECTION_CHARGES,
    currentEncounter: null,
    encounterBag: [],
    previousEncounterId: null,
    transitionRevision,
    ...runtime,
    pendingReward: null,
    lastReward: null,
    rewardCache: [],
    cacheMeter: 0,
    bonusCacheThreshold: 5,
    currency: {},
    activeSpellLoadout: resolveManastormActiveSpellLoadout(),
    messageRevision: 0,
    clientOverlay: createManastormClientOverlayState(),
    clientCue: null,
    clientCueRevision: 0,
  };
};

function cueFieldsForStatusTransition(
  state: ManastormClientRuntimeFields & Pick<ManastormRunState, "status">,
  nextStatus: string,
): Partial<ManastormClientRuntimeFields> {
  const cueId = manastormCueForStatusTransition(state.status, nextStatus);
  if (!cueId) return {};
  const revision = state.clientCueRevision + 1;
  return {
    clientCue: { cueId, revision },
    clientCueRevision: revision,
  };
}

function startOptions(
  randomOrOptions?: (() => number) | ManastormStartOptions,
): Required<Pick<ManastormStartOptions, "partySize" | "startingLevel">>
  & Omit<ManastormStartOptions, "partySize" | "startingLevel"> {
  if (typeof randomOrOptions === "function") {
    return {
      partySize: 5,
      startingLevel: 1,
      random: randomOrOptions,
    };
  }
  return {
    ...randomOrOptions,
    partySize: randomOrOptions?.partySize ?? 5,
    startingLevel: randomOrOptions?.startingLevel ?? 1,
  };
}

const MAX_PERSISTED_CACHE_ID_LENGTH = 160;

function uniqueCacheInstanceId(
  baseId: string,
  caches: readonly ManastormRewardCacheState[],
): string {
  const usedIds = new Set(caches.map(({ id }) => id));
  if (!usedIds.has(baseId)) return baseId;
  for (let instance = 2; ; instance += 1) {
    const suffix = `:instance-${instance}`;
    const candidate = `${baseId.slice(0, MAX_PERSISTED_CACHE_ID_LENGTH - suffix.length)}${suffix}`;
    if (!usedIds.has(candidate)) return candidate;
  }
}

function grantedRewardState(
  state: ManastormRunState,
  reward: ManastormRewardState,
  random: () => number,
): Partial<ManastormRunState> {
  const rewardCache = [...state.rewardCache];
  const cacheChance = reward.cachePolicy === "accumulating-chance"
    ? manastormCacheChance(state.level, state.cacheMeter)
    : 0;
  const chanceAwarded = reward.cachePolicy === "accumulating-chance"
    && random() < cacheChance;
  const cacheAwarded = reward.cachePolicy === "guaranteed" || chanceAwarded;
  const badLuckAwarded = chanceAwarded && state.cacheMeter >= state.bonusCacheThreshold - 1;
  const awardedCache = reward.cacheId && cacheAwarded
    ? [
      {
        id: uniqueCacheInstanceId(reward.id, rewardCache),
        cacheId: badLuckAwarded ? "manastorm-bonus-cache" : reward.cacheId,
        rewardId: reward.rewardId,
        stageId: reward.stageId,
        level: reward.level,
        rewardMultiplier: reward.rewardMultiplier,
      },
    ]
    : [];
  rewardCache.push(...awardedCache);
  // The meter protects against consecutive cacheless clears. A normal cache
  // satisfies the protection immediately, so it resets the streak without
  // also producing the guaranteed bonus cache.
  const accumulatedMeter = cacheAwarded
    ? 0
    : state.cacheMeter + 1;
  const bonusCacheEarned = reward.cachePolicy === "none"
    && accumulatedMeter >= state.bonusCacheThreshold;
  const bonusCache = bonusCacheEarned
    ? [{
      id: uniqueCacheInstanceId(`${reward.id}:bonus-cache`, rewardCache),
      cacheId: "manastorm-bonus-cache",
      rewardId: "bonus-cache-bad-luck-protection",
      stageId: reward.stageId,
      level: reward.level,
      rewardMultiplier: reward.rewardMultiplier,
    }]
    : [];
  rewardCache.push(...bonusCache);
  return {
    pendingReward: null,
    lastReward: reward,
    rewardCache,
    cacheMeter: bonusCacheEarned ? 0 : accumulatedMeter,
    currency: {
      ...state.currency,
      [reward.currencyId]: (state.currency[reward.currencyId] ?? 0) + reward.currencyAmount,
    },
  };
}

export const useManastormStore = create<ManastormState>((set, get) => ({
  ...initialRunState(),

  startRun: (randomOrOptions) => {
    const options = startOptions(randomOrOptions);
    const partySize = normalizeManastormPartySize(options.partySize);
    const maximumLevel = safeMaximumLevel();
    const level = Math.max(1, Math.min(maximumLevel, Math.trunc(options.startingLevel)));
    const unlockedThroughLevel = Math.max(
      level,
      Math.min(
        maximumLevel,
        Math.trunc(options.unlockedThroughLevel ?? level),
      ),
    );
    const catalog = getManastormCatalog();
    const modeId = Math.trunc(options.modeId ?? manastormModeId(catalog));
    const draw = drawManastormStage(
      level,
      partySize,
      [],
      null,
      options.random ?? Math.random,
      catalog,
      modeId,
      unlockedThroughLevel,
    );
    const runtime = runtimeFields(
      level,
      partySize,
      options.loadoutId,
      modeId,
      unlockedThroughLevel,
    );
    const activeSpellLoadout = resolveManastormActiveSpellLoadout(options.activeSpellLoadout);
    set((state) => ({
      ...initialRunState(partySize, state.transitionRevision + 1),
      status: "entering",
      phase: "enter",
      level,
      maximumLevel,
      unlockedThroughLevel,
      completed: level - 1,
      checkpointLevel: manastormCheckpointForLevel(level),
      milestone: isManastormSpecialLevel(level),
      currentEncounter: draw.encounter,
      encounterBag: draw.remainingBag,
      ...runtime,
      activeSpellLoadout,
      cacheMeter: Math.max(0, Math.trunc(options.cacheMeter ?? 0)),
      rewardCache: options.rewardCaches
        ? Object.freeze(options.rewardCaches.map((cache) => Object.freeze({ ...cache })))
        : Object.freeze([]),
      message: activeSpellLoadout.validationError
        ? `Local active-spell selection ignored: ${activeSpellLoadout.validationError}`
        : runtime.message,
      messageRevision: state.messageRevision + 1,
    }));
    return draw.encounter;
  },

  enterStage: () => {
    const state = get();
    if (state.status !== "entering" || !state.currentEncounter) return false;
    set({
      status: "clearing-trash",
      phase: "trash",
      message: `Break Chaotic Link by clearing guardians, or challenge empowered ${state.currentEncounter.bossName} now.`,
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  observeTrash: (cleared) => set((state) => {
    if (state.status !== "clearing-trash" || !cleared || !state.currentEncounter) return state;
    return {
      status: "fighting",
      phase: "boss",
      message: `Defeat ${state.currentEncounter.bossName}.`,
      messageRevision: state.messageRevision + 1,
    };
  }),

  observeBoss: (dead, looted, random = Math.random) => set((state) => {
    if (
      state.status !== "fighting"
      && state.status !== "awaiting-loot"
    ) return state;
    if (!dead || !state.currentEncounter) return state;
    const pendingReward = state.pendingReward ?? manastormReward(
      state.currentEncounter,
      state.level,
      state.partySize,
      getManastormCatalog(),
      state.modeId,
    );
    if (!looted) {
      if (state.status === "awaiting-loot" && state.pendingReward === pendingReward) return state;
      return {
        status: "awaiting-loot",
        phase: "loot",
        pendingReward,
        message: `Claim ${state.currentEncounter.bossName}'s reward.`,
        messageRevision: state.messageRevision + 1,
      };
    }
    const completed = Math.max(state.completed, state.level);
    return {
      status: "portal-ready",
      phase: "portal",
      completed,
      checkpointLevel: isManastormSpecialLevel(state.level)
        ? state.level + 1
        : state.checkpointLevel,
      ...grantedRewardState(state, pendingReward, random),
      ...cueFieldsForStatusTransition(state, "portal-ready"),
      message: "The next Manastorm portal is open.",
      messageRevision: state.messageRevision + 1,
    };
  }),

  beginTransition: () => {
    const state = get();
    if (state.status !== "portal-ready") return false;
    set({
      status: "transitioning",
      phase: "next",
      clientOverlay: createManastormClientOverlayState(),
      message: "The storm is selecting the next stage.",
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  prepareNextEncounter: (random = Math.random) => {
    const state = get();
    if (state.status !== "transitioning" || !state.currentEncounter) return null;
    const completed = Math.max(state.completed, state.level);
    const nextLevel = state.level + 1;
    if (nextLevel > state.maximumLevel) {
      set({
        status: "completed",
        phase: "complete",
        completed,
        previousEncounterId: state.currentEncounter.id,
        currentEncounter: null,
        encounterBag: [],
        clientOverlay: createManastormClientOverlayState(),
        clientCue: null,
        message: "The final Manastorm collapses. Run complete.",
        messageRevision: state.messageRevision + 1,
      });
      return null;
    }
    const catalog = getManastormCatalog();
    const modeId = state.modeId;
    const draw = drawManastormStage(
      nextLevel,
      state.partySize,
      state.encounterBag,
      state.currentEncounter.id,
      random,
      catalog,
      modeId,
      Math.max(state.unlockedThroughLevel, nextLevel),
    );
    const nextUnlockedThroughLevel = Math.max(state.unlockedThroughLevel, nextLevel);
    const runtime = runtimeFields(
      nextLevel,
      state.partySize,
      state.loadoutId,
      modeId,
      nextUnlockedThroughLevel,
    );
    set({
      level: nextLevel,
      unlockedThroughLevel: nextUnlockedThroughLevel,
      completed,
      checkpointLevel: manastormCheckpointForLevel(nextLevel),
      milestone: isManastormSpecialLevel(nextLevel),
      currentEncounter: draw.encounter,
      encounterBag: draw.remainingBag,
      previousEncounterId: state.currentEncounter.id,
      transitionRevision: state.transitionRevision + 1,
      pendingReward: null,
      resurrectionCharges: state.maxResurrectionCharges,
      clientOverlay: createManastormClientOverlayState(),
      ...runtime,
      messageRevision: state.messageRevision + 1,
    });
    return draw.encounter;
  },

  finishTransition: () => set((state) => state.status === "transitioning"
    ? {
      status: "entering",
      phase: "enter",
      message: state.message,
      messageRevision: state.messageRevision + 1,
    }
    : state),

  useResurrectionCharge: () => {
    const state = get();
    if (
      state.status === "idle"
      || state.status === "failed"
      || state.status === "completed"
      || state.resurrectionCharges <= 0
    ) return false;
    set({
      resurrectionCharges: state.resurrectionCharges - 1,
      message: `${state.resurrectionCharges - 1} shared resurrection charge${state.resurrectionCharges - 1 === 1 ? "" : "s"} remaining.`,
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  restartFromCheckpoint: (random = Math.random) => {
    const state = get();
    if (state.status !== "failed") return null;
    const catalog = getManastormCatalog();
    const level = state.checkpointLevel;
    const modeId = state.modeId;
    const draw = drawManastormStage(
      level,
      state.partySize,
      [],
      state.previousEncounterId,
      random,
      catalog,
      modeId,
      state.unlockedThroughLevel,
    );
    const runtime = runtimeFields(
      level,
      state.partySize,
      state.loadoutId,
      modeId,
      state.unlockedThroughLevel,
    );
    set({
      status: "entering",
      phase: "enter",
      level,
      completed: level - 1,
      milestone: isManastormSpecialLevel(level),
      currentEncounter: draw.encounter,
      encounterBag: draw.remainingBag,
      resurrectionCharges: state.maxResurrectionCharges,
      pendingReward: null,
      clientOverlay: createManastormClientOverlayState(),
      clientCue: null,
      transitionRevision: state.transitionRevision + 1,
      ...runtime,
      messageRevision: state.messageRevision + 1,
    });
    return draw.encounter;
  },

  setPartySize: (partySize) => {
    const state = get();
    if (state.status !== "idle" && state.status !== "failed" && state.status !== "completed") return false;
    const normalized = normalizeManastormPartySize(partySize);
    const runtime = runtimeFields(
      state.level,
      normalized,
      state.loadoutId,
      state.modeId,
      state.unlockedThroughLevel,
    );
    set({
      partySize: normalized,
      ...runtime,
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  setLoadout: (loadoutId) => {
    const state = get();
    if (loadoutId !== null && !state.availableLoadoutIds.includes(loadoutId)) return false;
    set({
      loadoutId,
      message: loadoutId ? `Loadout selected: ${loadoutId}.` : "No Manastorm loadout selected.",
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  setActiveSpellLoadout: (selectedIds) => {
    const state = get();
    const validation = validateManastormActiveSpellLoadout(
      selectedIds,
      state.activeSpellLoadout.available,
      state.activeSpellLoadout.maxSelections,
    );
    if (!validation.ok) return false;
    set({
      activeSpellLoadout: {
        ...state.activeSpellLoadout,
        selectedIds: validation.selectedIds,
        selected: validation.selected,
        validationError: null,
      },
      message: validation.selectedIds.length
        ? `${validation.selectedIds.length} local active-spell selection${validation.selectedIds.length === 1 ? "" : "s"} prepared.`
        : "No local active-spell selections prepared.",
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  openRewardCache: (cacheId) => {
    const state = get();
    const cacheIndex = state.rewardCache.findIndex((candidate) => candidate.id === cacheId);
    const cache = state.rewardCache[cacheIndex];
    if (!cache) return false;
    const multiplier = Math.max(
      0,
      Number.isFinite(cache.rewardMultiplier) ? cache.rewardMultiplier ?? 1 : 1,
    );
    set({
      rewardCache: state.rewardCache.filter((_, index) => index !== cacheIndex),
      currency: {
        ...state.currency,
        bedlamBullions: (state.currency.bedlamBullions ?? 0) + Math.max(1, Math.round(multiplier)),
        bonzoBolts: (state.currency.bonzoBolts ?? 0)
          + Math.max(1, Math.round(Math.ceil(cache.level / 5) * multiplier)),
      },
      message: "Manastorm cache opened.",
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  setNextWaveCountdown: (seconds) => set((state) => ({
    clientOverlay: withManastormNextWaveCountdown(state.clientOverlay, seconds),
  })),

  setSafetyBubble: (update) => set((state) => ({
    clientOverlay: withManastormSafetyBubble(state.clientOverlay, update),
  })),

  requestClientCue: (cueId) => {
    if (!isManastormPortalCueId(cueId)) return false;
    set((state) => {
      const revision = state.clientCueRevision + 1;
      return {
        clientCue: { cueId, revision },
        clientCueRevision: revision,
      };
    });
    return true;
  },

  clearClientCue: () => set({ clientCue: null }),

  failRun: () => {
    const state = get();
    if (state.status === "idle" || state.status === "failed" || state.status === "completed") return false;
    set({
      status: "failed",
      phase: "failed",
      clientOverlay: createManastormClientOverlayState(),
      clientCue: null,
      message: `Run failed. Checkpoint ${state.checkpointLevel} is available.`,
      messageRevision: state.messageRevision + 1,
    });
    return true;
  },

  resetRun: () => set((state) => initialRunState(state.partySize, state.transitionRevision + 1)),
}));