import BattleScene from "#app/battle-scene.js";
import { BattlerIndex } from "#app/battle.js";
import { applyPreAttackAbAttrs, AddSecondStrikeAbAttr, IgnoreMoveEffectsAbAttr, applyPostDefendAbAttrs, PostDefendAbAttr, applyPostAttackAbAttrs, PostAttackAbAttr, MaxMultiHitAbAttr, AlwaysHitAbAttr } from "#app/data/ability.js";
import { ArenaTagSide, ConditionalProtectTag } from "#app/data/arena-tag.js";
import { MoveAnim } from "#app/data/battle-anims.js";
import { BattlerTagLapseType, ProtectedTag, SemiInvulnerableTag } from "#app/data/battler-tags.js";
import { MoveTarget, applyMoveAttrs, OverrideMoveEffectAttr, MultiHitAttr, AttackMove, FixedDamageAttr, VariableTargetAttr, MissEffectAttr, MoveFlags, applyFilteredMoveAttrs, MoveAttr, MoveEffectAttr, MoveEffectTrigger, ChargeAttr, MoveCategory, NoEffectAttr, HitsTagAttr } from "#app/data/move.js";
import { SpeciesFormChangePostMoveTrigger } from "#app/data/pokemon-forms.js";
import { BattlerTagType } from "#app/enums/battler-tag-type.js";
import { Moves } from "#app/enums/moves.js";
import Pokemon, { PokemonMove, MoveResult, HitResult } from "#app/field/pokemon.js";
import { getPokemonNameWithAffix } from "#app/messages.js";
import { PokemonMultiHitModifier, FlinchChanceModifier, EnemyAttackStatusEffectChanceModifier, ContactHeldItemTransferChanceModifier, HitHealModifier } from "#app/modifier/modifier.js";
import i18next from "i18next";
import * as Utils from "#app/utils.js";
import { PokemonPhase } from "./pokemon-phase";

export class MoveEffectPhase extends PokemonPhase {
  public move: PokemonMove;
  protected targets: BattlerIndex[];

  constructor(scene: BattleScene, battlerIndex: BattlerIndex, targets: BattlerIndex[], move: PokemonMove) {
    super(scene, battlerIndex);
    this.move = move;
    /**
       * In double battles, if the right Pokemon selects a spread move and the left Pokemon dies
       * with no party members available to switch in, then the right Pokemon takes the index
       * of the left Pokemon and gets hit unless this is checked.
       */
    if (targets.includes(battlerIndex) && this.move.getMove().moveTarget === MoveTarget.ALL_NEAR_OTHERS) {
      const i = targets.indexOf(battlerIndex);
      targets.splice(i, i + 1);
    }
    this.targets = targets;
  }

  start() {
    super.start();

    /** The Pokemon using this phase's invoked move */
    const user = this.getUserPokemon();
    /** All Pokemon targeted by this phase's invoked move */
    const targets = this.getTargets();

    /** If the user was somehow removed from the field, end this phase */
    if (!user?.isOnField()) {
      return super.end();
    }

    /**
       * Does an effect from this move override other effects on this turn?
       * e.g. Charging moves (Fly, etc.) on their first turn of use.
       */
    const overridden = new Utils.BooleanHolder(false);
    /** The {@linkcode Move} object from {@linkcode allMoves} invoked by this phase */
    const move = this.move.getMove();

    // Assume single target for override
    applyMoveAttrs(OverrideMoveEffectAttr, user, this.getTarget() ?? null, move, overridden, this.move.virtual).then(() => {
      // If other effects were overriden, stop this phase before they can be applied
      if (overridden.value) {
        return this.end();
      }

      user.lapseTags(BattlerTagLapseType.MOVE_EFFECT);

      /**
         * If this phase is for the first hit of the invoked move,
         * resolve the move's total hit count. This block combines the
         * effects of the move itself, Parental Bond, and Multi-Lens to do so.
         */
      if (user.turnData.hitsLeft === undefined) {
        const hitCount = new Utils.IntegerHolder(1);
        // Assume single target for multi hit
        applyMoveAttrs(MultiHitAttr, user, this.getTarget() ?? null, move, hitCount);
        // If Parental Bond is applicable, double the hit count
        applyPreAttackAbAttrs(AddSecondStrikeAbAttr, user, null, move, false, targets.length, hitCount, new Utils.IntegerHolder(0));
        // If Multi-Lens is applicable, multiply the hit count by 1 + the number of Multi-Lenses held by the user
        if (move instanceof AttackMove && !move.hasAttr(FixedDamageAttr)) {
          this.scene.applyModifiers(PokemonMultiHitModifier, user.isPlayer(), user, hitCount, new Utils.IntegerHolder(0));
        }
        // Set the user's relevant turnData fields to reflect the final hit count
        user.turnData.hitCount = hitCount.value;
        user.turnData.hitsLeft = hitCount.value;
      }

      /**
         * Log to be entered into the user's move history once the move result is resolved.
         * Note that `result` (a {@linkcode MoveResult}) logs whether the move was successfully
         * used in the sense of "Does it have an effect on the user?".
         */
      const moveHistoryEntry = { move: this.move.moveId, targets: this.targets, result: MoveResult.PENDING, virtual: this.move.virtual };

      /**
         * Stores results of hit checks of the invoked move against all targets, organized by battler index.
         * @see {@linkcode hitCheck}
         */
      const targetHitChecks = Object.fromEntries(targets.map(p => [p.getBattlerIndex(), this.hitCheck(p)]));
      const hasActiveTargets = targets.some(t => t.isActive(true));
      /**
         * If no targets are left for the move to hit (FAIL), or the invoked move is single-target
         * (and not random target) and failed the hit check against its target (MISS), log the move
         * as FAILed or MISSed (depending on the conditions above) and end this phase.
         */
      if (!hasActiveTargets || (!move.hasAttr(VariableTargetAttr) && !move.isMultiTarget() && !targetHitChecks[this.targets[0]])) {
        this.stopMultiHit();
        if (hasActiveTargets) {
          this.scene.queueMessage(i18next.t("battle:attackMissed", { pokemonNameWithAffix: this.getTarget()? getPokemonNameWithAffix(this.getTarget()!) : "" }));
          moveHistoryEntry.result = MoveResult.MISS;
          applyMoveAttrs(MissEffectAttr, user, null, move);
        } else {
          this.scene.queueMessage(i18next.t("battle:attackFailed"));
          moveHistoryEntry.result = MoveResult.FAIL;
        }
        user.pushMoveHistory(moveHistoryEntry);
        return this.end();
      }

      /** All move effect attributes are chained together in this array to be applied asynchronously. */
      const applyAttrs: Promise<void>[] = [];

      // Move animation only needs one target
      new MoveAnim(move.id as Moves, user, this.getTarget()?.getBattlerIndex()!).play(this.scene, () => { // TODO: is the bang correct here?
        /** Has the move successfully hit a target (for damage) yet? */
        let hasHit: boolean = false;
        for (const target of targets) {
          /**
             * If the move missed a target, stop all future hits against that target
             * and move on to the next target (if there is one).
             */
          if (!targetHitChecks[target.getBattlerIndex()]) {
            this.stopMultiHit(target);
            this.scene.queueMessage(i18next.t("battle:attackMissed", { pokemonNameWithAffix: getPokemonNameWithAffix(target) }));
            if (moveHistoryEntry.result === MoveResult.PENDING) {
              moveHistoryEntry.result = MoveResult.MISS;
            }
            user.pushMoveHistory(moveHistoryEntry);
            applyMoveAttrs(MissEffectAttr, user, null, move);
            continue;
          }

          /** The {@linkcode ArenaTagSide} to which the target belongs */
          const targetSide = target.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
          /** Has the invoked move been cancelled by conditional protection (e.g Quick Guard)? */
          const hasConditionalProtectApplied = new Utils.BooleanHolder(false);
          /** Does the applied conditional protection bypass Protect-ignoring effects? */
          const bypassIgnoreProtect = new Utils.BooleanHolder(false);
          // If the move is not targeting a Pokemon on the user's side, try to apply conditional protection effects
          if (!this.move.getMove().isAllyTarget()) {
            this.scene.arena.applyTagsForSide(ConditionalProtectTag, targetSide, hasConditionalProtectApplied, user, target, move.id, bypassIgnoreProtect);
          }

          /** Is the target protected by Protect, etc. or a relevant conditional protection effect? */
          const isProtected = (bypassIgnoreProtect.value || !this.move.getMove().checkFlag(MoveFlags.IGNORE_PROTECT, user, target))
              && (hasConditionalProtectApplied.value || target.findTags(t => t instanceof ProtectedTag).find(t => target.lapseTag(t.tagType)));

          /** Does this phase represent the invoked move's first strike? */
          const firstHit = (user.turnData.hitsLeft === user.turnData.hitCount);

          // Only log the move's result on the first strike
          if (firstHit) {
            user.pushMoveHistory(moveHistoryEntry);
          }

          /**
             * Since all fail/miss checks have applied, the move is considered successfully applied.
             * It's worth noting that if the move has no effect or is protected against, this assignment
             * is overwritten and the move is logged as a FAIL.
             */
          moveHistoryEntry.result = MoveResult.SUCCESS;

          /**
             * Stores the result of applying the invoked move to the target.
             * If the target is protected, the result is always `NO_EFFECT`.
             * Otherwise, the hit result is based on type effectiveness, immunities,
             * and other factors that may negate the attack or status application.
             *
             * Internally, the call to {@linkcode Pokemon.apply} is where damage is calculated
             * (for attack moves) and the target's HP is updated. However, this isn't
             * made visible to the user until the resulting {@linkcode DamagePhase}
             * is invoked.
             */
          const hitResult = !isProtected ? target.apply(user, move) : HitResult.NO_EFFECT;

          /** Does {@linkcode hitResult} indicate that damage was dealt to the target? */
          const dealsDamage = [
            HitResult.EFFECTIVE,
            HitResult.SUPER_EFFECTIVE,
            HitResult.NOT_VERY_EFFECTIVE,
            HitResult.ONE_HIT_KO
          ].includes(hitResult);

          /** Is this target the first one hit by the move on its current strike? */
          const firstTarget = dealsDamage && !hasHit;
          if (firstTarget) {
            hasHit = true;
          }

          /**
             * If the move has no effect on the target (i.e. the target is protected or immune),
             * change the logged move result to FAIL.
             */
          if (hitResult === HitResult.NO_EFFECT) {
            moveHistoryEntry.result = MoveResult.FAIL;
          }

          /** Does this phase represent the invoked move's last strike? */
          const lastHit = (user.turnData.hitsLeft === 1 || !this.getTarget()?.isActive());

          /**
             * If the user can change forms by using the invoked move,
             * it only changes forms after the move's last hit
             * (see Relic Song's interaction with Parental Bond when used by Meloetta).
             */
          if (lastHit) {
            this.scene.triggerPokemonFormChange(user, SpeciesFormChangePostMoveTrigger);
          }

          /**
             * Create a Promise that applys *all* effects from the invoked move's MoveEffectAttrs.
             * These are ordered by trigger type (see {@linkcode MoveEffectTrigger}), and each trigger
             * type requires different conditions to be met with respect to the move's hit result.
             */
          applyAttrs.push(new Promise(resolve => {
            // Apply all effects with PRE_MOVE triggers (if the target isn't immune to the move)
            applyFilteredMoveAttrs((attr: MoveAttr) => attr instanceof MoveEffectAttr && attr.trigger === MoveEffectTrigger.PRE_APPLY && (!attr.firstHitOnly || firstHit) && (!attr.lastHitOnly || lastHit) && hitResult !== HitResult.NO_EFFECT,
              user, target, move).then(() => {
              // All other effects require the move to not have failed or have been cancelled to trigger
              if (hitResult !== HitResult.FAIL) {
                /** Are the move's effects tied to the first turn of a charge move? */
                const chargeEffect = !!move.getAttrs(ChargeAttr).find(ca => ca.usedChargeEffect(user, this.getTarget() ?? null, move));
                /**
                   * If the invoked move's effects are meant to trigger during the move's "charge turn,"
                   * ignore all effects after this point.
                   * Otherwise, apply all self-targeted POST_APPLY effects.
                   */
                Utils.executeIf(!chargeEffect, () => applyFilteredMoveAttrs((attr: MoveAttr) => attr instanceof MoveEffectAttr && attr.trigger === MoveEffectTrigger.POST_APPLY
                      && attr.selfTarget && (!attr.firstHitOnly || firstHit) && (!attr.lastHitOnly || lastHit), user, target, move)).then(() => {
                  // All effects past this point require the move to have hit the target
                  if (hitResult !== HitResult.NO_EFFECT) {
                    // Apply all non-self-targeted POST_APPLY effects
                    applyFilteredMoveAttrs((attr: MoveAttr) => attr instanceof MoveEffectAttr && (attr as MoveEffectAttr).trigger === MoveEffectTrigger.POST_APPLY
                        && !(attr as MoveEffectAttr).selfTarget && (!attr.firstHitOnly || firstHit) && (!attr.lastHitOnly || lastHit), user, target, this.move.getMove()).then(() => {
                      /**
                         * If the move hit, and the target doesn't have Shield Dust,
                         * apply the chance to flinch the target gained from King's Rock
                         */
                      if (dealsDamage && !target.hasAbilityWithAttr(IgnoreMoveEffectsAbAttr)) {
                        const flinched = new Utils.BooleanHolder(false);
                        user.scene.applyModifiers(FlinchChanceModifier, user.isPlayer(), user, flinched);
                        if (flinched.value) {
                          target.addTag(BattlerTagType.FLINCHED, undefined, this.move.moveId, user.id);
                        }
                      }
                      // If the move was not protected against, apply all HIT effects
                      Utils.executeIf(!isProtected && !chargeEffect, () => applyFilteredMoveAttrs((attr: MoveAttr) => attr instanceof MoveEffectAttr && (attr as MoveEffectAttr).trigger === MoveEffectTrigger.HIT
                            && (!attr.firstHitOnly || firstHit) && (!attr.lastHitOnly || lastHit) && (!attr.firstTargetOnly || firstTarget), user, target, this.move.getMove()).then(() => {
                        // Apply the target's post-defend ability effects (as long as the target is active or can otherwise apply them)
                        return Utils.executeIf(!target.isFainted() || target.canApplyAbility(), () => applyPostDefendAbAttrs(PostDefendAbAttr, target, user, this.move.getMove(), hitResult).then(() => {
                          // If the invoked move is an enemy attack, apply the enemy's status effect-inflicting tags and tokens
                          target.lapseTag(BattlerTagType.BEAK_BLAST_CHARGING);
                          if (move.category === MoveCategory.PHYSICAL && user.isPlayer() !== target.isPlayer()) {
                            target.lapseTag(BattlerTagType.SHELL_TRAP);
                          }
                          if (!user.isPlayer() && this.move.getMove() instanceof AttackMove) {
                            user.scene.applyShuffledModifiers(this.scene, EnemyAttackStatusEffectChanceModifier, false, target);
                          }
                        })).then(() => {
                          // Apply the user's post-attack ability effects
                          applyPostAttackAbAttrs(PostAttackAbAttr, user, target, this.move.getMove(), hitResult).then(() => {
                            /**
                               * If the invoked move is an attack, apply the user's chance to
                               * steal an item from the target granted by Grip Claw
                               */
                            if (this.move.getMove() instanceof AttackMove) {
                              this.scene.applyModifiers(ContactHeldItemTransferChanceModifier, this.player, user, target);
                            }
                            resolve();
                          });
                        });
                      })
                      ).then(() => resolve());
                    });
                  } else {
                    applyMoveAttrs(NoEffectAttr, user, null, move).then(() => resolve());
                  }
                });
              } else {
                resolve();
              }
            });
          }));
        }
        // Apply the move's POST_TARGET effects on the move's last hit, after all targeted effects have resolved
        const postTarget = (user.turnData.hitsLeft === 1 || !this.getTarget()?.isActive()) ?
          applyFilteredMoveAttrs((attr: MoveAttr) => attr instanceof MoveEffectAttr && attr.trigger === MoveEffectTrigger.POST_TARGET, user, null, move) :
          null;

        if (!!postTarget) {
          if (applyAttrs.length) { // If there is a pending asynchronous move effect, do this after
            applyAttrs[applyAttrs.length - 1]?.then(() => postTarget);
          } else { // Otherwise, push a new asynchronous move effect
            applyAttrs.push(postTarget);
          }
        }

        // Wait for all move effects to finish applying, then end this phase
        Promise.allSettled(applyAttrs).then(() => this.end());
      });
    });
  }

  end() {
    const user = this.getUserPokemon();
    /**
       * If this phase isn't for the invoked move's last strike,
       * unshift another MoveEffectPhase for the next strike.
       * Otherwise, queue a message indicating the number of times the move has struck
       * (if the move has struck more than once), then apply the heal from Shell Bell
       * to the user.
       */
    if (user) {
      if (user.turnData.hitsLeft && --user.turnData.hitsLeft >= 1 && this.getTarget()?.isActive()) {
        this.scene.unshiftPhase(this.getNewHitPhase());
      } else {
        // Queue message for number of hits made by multi-move
        // If multi-hit attack only hits once, still want to render a message
        const hitsTotal = user.turnData.hitCount! - Math.max(user.turnData.hitsLeft!, 0); // TODO: are those bangs correct?
        if (hitsTotal > 1 || (user.turnData.hitsLeft && user.turnData.hitsLeft > 0)) {
          // If there are multiple hits, or if there are hits of the multi-hit move left
          this.scene.queueMessage(i18next.t("battle:attackHitsCount", { count: hitsTotal }));
        }
        this.scene.applyModifiers(HitHealModifier, this.player, user);
      }
    }

    super.end();
  }

  /**
     * Resolves whether this phase's invoked move hits or misses the given target
     * @param target {@linkcode Pokemon} the Pokemon targeted by the invoked move
     * @returns `true` if the move does not miss the target; `false` otherwise
     */
  hitCheck(target: Pokemon): boolean {
    // Moves targeting the user and entry hazards can't miss
    if ([MoveTarget.USER, MoveTarget.ENEMY_SIDE].includes(this.move.getMove().moveTarget)) {
      return true;
    }

    const user = this.getUserPokemon()!; // TODO: is this bang correct?

    // Hit check only calculated on first hit for multi-hit moves unless flag is set to check all hits.
    // However, if an ability with the MaxMultiHitAbAttr, namely Skill Link, is present, act as a normal
    // multi-hit move and proceed with all hits
    if (user.turnData.hitsLeft < user.turnData.hitCount) {
      if (!this.move.getMove().hasFlag(MoveFlags.CHECK_ALL_HITS) || user.hasAbilityWithAttr(MaxMultiHitAbAttr)) {
        return true;
      }
    }

    if (user.hasAbilityWithAttr(AlwaysHitAbAttr) || target.hasAbilityWithAttr(AlwaysHitAbAttr)) {
      return true;
    }

    // If the user should ignore accuracy on a target, check who the user targeted last turn and see if they match
    if (user.getTag(BattlerTagType.IGNORE_ACCURACY) && (user.getLastXMoves().find(() => true)?.targets || []).indexOf(target.getBattlerIndex()) !== -1) {
      return true;
    }

    if (target.getTag(BattlerTagType.ALWAYS_GET_HIT)) {
      return true;
    }

    const semiInvulnerableTag = target.getTag(SemiInvulnerableTag);
    if (semiInvulnerableTag && !this.move.getMove().getAttrs(HitsTagAttr).some(hta => hta.tagType === semiInvulnerableTag.tagType)) {
      return false;
    }

    const moveAccuracy = this.move.getMove().calculateBattleAccuracy(user!, target); // TODO: is the bang correct here?

    if (moveAccuracy === -1) {
      return true;
    }

    const accuracyMultiplier = user.getAccuracyMultiplier(target, this.move.getMove());
    const rand = user.randSeedInt(100, 1);

    return rand <= moveAccuracy * (accuracyMultiplier!); // TODO: is this bang correct?
  }

  /** Returns the {@linkcode Pokemon} using this phase's invoked move */
  getUserPokemon(): Pokemon | undefined {
    if (this.battlerIndex > BattlerIndex.ENEMY_2) {
      return this.scene.getPokemonById(this.battlerIndex) ?? undefined;
    }
    return (this.player ? this.scene.getPlayerField() : this.scene.getEnemyField())[this.fieldIndex];
  }

  /** Returns an array of all {@linkcode Pokemon} targeted by this phase's invoked move */
  getTargets(): Pokemon[] {
    return this.scene.getField(true).filter(p => this.targets.indexOf(p.getBattlerIndex()) > -1);
  }

  /** Returns the first target of this phase's invoked move */
  getTarget(): Pokemon | undefined {
    return this.getTargets()[0];
  }

  /**
     * Removes the given {@linkcode Pokemon} from this phase's target list
     * @param target {@linkcode Pokemon} the Pokemon to be removed
     */
  removeTarget(target: Pokemon): void {
    const targetIndex = this.targets.findIndex(ind => ind === target.getBattlerIndex());
    if (targetIndex !== -1) {
      this.targets.splice(this.targets.findIndex(ind => ind === target.getBattlerIndex()), 1);
    }
  }

  /**
     * Prevents subsequent strikes of this phase's invoked move from occurring
     * @param target {@linkcode Pokemon} if defined, only stop subsequent
     * strikes against this Pokemon
     */
  stopMultiHit(target?: Pokemon): void {
    /** If given a specific target, remove the target from subsequent strikes */
    if (target) {
      this.removeTarget(target);
    }
    /**
       * If no target specified, or the specified target was the last of this move's
       * targets, completely cancel all subsequent strikes.
      */
    if (!target || this.targets.length === 0 ) {
        this.getUserPokemon()!.turnData.hitCount = 1; // TODO: is the bang correct here?
        this.getUserPokemon()!.turnData.hitsLeft = 1; // TODO: is the bang correct here?
    }
  }

  /** Returns a new MoveEffectPhase with the same properties as this phase */
  getNewHitPhase() {
    return new MoveEffectPhase(this.scene, this.battlerIndex, this.targets, this.move);
  }
}