import type { DungeonBossObjective, DungeonDefinition, DungeonExpansion } from "./dungeonTypes";
import {
  normalizeEnemyAttack,
  type EnemyAbilityCondition,
  type EnemyAbilityEffect,
  type EnemyAttackDefinition,
  type EnemyAttackTarget,
  type EnemyAttackTelegraph,
} from "./enemyAttacks";
import type { PopulationEntityDefinition } from "./mobPopulation";
import { enemyTriggeredShoutContract } from "./enemyTriggeredShouts";

export type BossGuideFidelity = "source" | "fallback" | "authored";

export interface BossMechanicGuideOverride {
  readonly trigger?: string;
  readonly timing?: string;
  readonly targetAndEffect?: string;
  readonly telegraph?: string;
  readonly counterplay?: string;
  readonly testInstruction?: string;
}

export type BossMechanicGuideOverrides = Readonly<Record<string, BossMechanicGuideOverride>>;

export interface BossMechanicGuideEntry {
  readonly id: string;
  readonly name: string;
  readonly trigger: string;
  readonly timing: string;
  readonly targetAndEffect: string;
  readonly telegraph: string;
  readonly counterplay: string;
  readonly testInstruction: string;
  readonly fidelity: BossGuideFidelity;
  readonly fidelityLabel: string;
  readonly sourceDetail: string;
}

export interface BossGuideEntry {
  readonly id: string;
  readonly name: string;
  readonly title?: string;
  readonly entityId?: string;
  readonly mechanics: readonly BossMechanicGuideEntry[];
}

export interface DungeonBossGuide {
  readonly id: string;
  readonly title: string;
  readonly expansion: DungeonExpansion;
  readonly bosses: readonly BossGuideEntry[];
}

export function bossGuideOverrideKey(
  dungeonId: string,
  bossEntityId: string,
  mechanicId: string,
): string {
  return `${dungeonId}:${bossEntityId}:${mechanicId}`;
}

function seconds(milliseconds: number): string {
  const value = milliseconds / 1_000;
  return Number.isInteger(value) ? `${value}s` : `${value.toFixed(1)}s`;
}

function rangeSeconds(range: readonly [number, number]): string {
  return range[0] === range[1]
    ? seconds(range[0])
    : `${seconds(range[0])}–${seconds(range[1])}`;
}

function titleCase(value: string): string {
  return value.replace(/-/g, " ").replace(/\b\w/g, (letter) => letter.toUpperCase());
}

function describeCondition(condition: EnemyAbilityCondition | undefined): string {
  if (!condition || condition.kind === "in-combat") return "While the boss is in combat";
  if (condition.kind === "self-health-percent") {
    if (condition.minimum > 0) {
      return `While the boss is between ${Math.round(condition.minimum)}% and ${Math.round(condition.maximum)}% health`;
    }
    return `When the boss reaches ${Math.round(condition.maximum)}% health`;
  }
  if (condition.kind === "friendly-missing-health") {
    return `When an ally within ${condition.range}m is missing ${Math.round(condition.amount)} health`;
  }
  if (condition.kind === "friendly-missing-aura") {
    return `When an ally within ${condition.range}m is missing this buff`;
  }
  return `While encounter ${condition.encounterId} is in: ${condition.states.join(", ")}`;
}

function describeTiming(attack: EnemyAttackDefinition): string {
  const parts: string[] = [];
  if (attack.initialCooldownMs) parts.push(`First: ${rangeSeconds(attack.initialCooldownMs)}`);
  if (attack.repeatCooldownMs) parts.push(`Repeats: ${rangeSeconds(attack.repeatCooldownMs)}`);
  else if (attack.cooldownMs > 0) parts.push(`Cooldown: ${seconds(attack.cooldownMs)}`);
  if ((attack.castTimeMs ?? 0) > 0) parts.push(`Cast: ${seconds(attack.castTimeMs!)}`);
  if (attack.maximumCasts) parts.push(`Maximum uses: ${attack.maximumCasts}`);
  return parts.join(" · ") || "Immediate encounter action";
}

const TARGET_LABELS: Readonly<Record<EnemyAttackTarget, string>> = {
  primary: "the boss's current target",
  "random-party": "a random party member",
  "nearby-party": "party members in the affected area",
  "nearby-friendly": "the boss and nearby enemy allies",
  self: "the boss",
  "lowest-health-friendly": "the lowest-health enemy ally",
  "selected-friendly": "the boss's selected ally",
};

function describeEffect(effect: EnemyAbilityEffect | undefined, attack: EnemyAttackDefinition): string {
  const target = TARGET_LABELS[attack.target];
  if (!effect || effect.kind === "damage") {
    const multiplier = effect?.multiplier ?? attack.damageMultiplier;
    return `${titleCase(attack.school)} damage to ${target} (${Number(multiplier.toFixed(2))}× boss power)`;
  }
  if (effect.kind === "heal") return `Heals ${target} for ${effect.multiplier}× boss power`;
  if (effect.kind === "dot") return `${titleCase(attack.school)} ${effect.wowPeriodicSource ? "bleed " : ""}damage to ${target} every ${seconds(effect.intervalMs)} for ${effect.ticks} ticks${effect.wowPeriodicSource ? "; ignores armor" : "; dispellable"}`;
  if (effect.kind === "leech") {
    return `Drains ${target} for ${effect.damageMultiplier}× boss power and heals the caster for ${effect.healMultiplier}× boss power`;
  }
  if (effect.kind === "composite") {
    return effect.effects.map((entry) => describeEffect(entry, attack)).join("; ");
  }
  if (effect.kind === "aura") {
    if (effect.meleeAutoCriticalProc) {
      const proc = effect.meleeAutoCriticalProc;
      return `Applies ${titleCase(effect.aura)} to ${target}; successful main-hand autos have a ${Math.round(proc.chance * 100)}% chance to grant ${proc.charges} charge${proc.charges === 1 ? "" : "s"} of +${proc.criticalChancePercent}% critical chance to the next main-hand auto for ${seconds(proc.durationMs)}`;
    }
    const magnitude = effect.magnitude === undefined ? "" : ` at ${effect.magnitude} strength`;
    return `Applies ${titleCase(effect.aura)} to ${target} for ${seconds(effect.durationMs)}${magnitude}`;
  }
  if (effect.kind === "target-aura") {
    return `Applies ${titleCase(effect.aura)} to ${target} for ${seconds(effect.durationMs)}`;
  }
  if (effect.kind === "control") {
    const damage = effect.damageMultiplier === undefined
      ? ""
      : `${titleCase(attack.school)} damage (${Number(effect.damageMultiplier.toFixed(2))}× boss power) and `;
    return `${damage}${titleCase(effect.mechanic)} controls ${target} for ${seconds(effect.durationMs)}`;
  }
  if (effect.kind === "transform") return `Transforms ${target} into ${titleCase(effect.form)}`;
  if (effect.kind === "triggered-shout") {
    const contract = enemyTriggeredShoutContract(effect.sourceSpellId, effect.sourceProfile);
    if (!contract) return "Controls the cast victim and nearby party members";
    const child = contract.childEffects.find((entry) => entry.kind === "control");
    return `${child?.kind === "control" ? titleCase(child.mechanic) : "Control"} on the cast victim for ${seconds(contract.childSignature.durationMs)}; fear within ${contract.targeting.parentArea.radiusYards}m of the boss for ${seconds(contract.parentSignature.durationMs)}${contract.targeting.parentArea.maximumTargets ? ` (up to ${contract.targeting.parentArea.maximumTargets} party members)` : ""}${contract.childEffects.some((entry) => entry.kind === "damage-taken") ? "; cast victim takes 15% more physical damage" : ""}`;
  }
  if (effect.kind === "weapon-capability") return `Allows ${target} to dual wield`;
  if (effect.kind === "extra-attacks") return `Grants ${effect.count} extra attacks to ${target}`;
  if (effect.kind === "pull") return `Pulls ${target} to the boss`;
  if (effect.kind === "summon") return `Summons ${effect.count} add${effect.count === 1 ? "" : "s"} (creature ${effect.creatureEntry})`;
  if (effect.kind === "call-for-help") return `Calls hostile allies within ${effect.radius}m into combat`;
  return `Advances encounter event “${effect.eventId}”`;
}

function describeTelegraph(telegraph: EnemyAttackTelegraph | undefined, attack: EnemyAttackDefinition): string {
  if (!telegraph) {
    const warning = (attack.castTimeMs ?? 0) > 0 ? ` with a ${seconds(attack.castTimeMs!)} cast warning` : "";
    const effects = attack.effect?.kind === "composite"
      ? attack.effect.effects
      : attack.effect ? [attack.effect] : [];
    return effects.length > 0 && effects.every((effect) => (
      effect.kind === "heal"
      || effect.kind === "aura"
      || effect.kind === "transform"
      || effect.kind === "summon"
      || effect.kind === "call-for-help"
      || effect.kind === "encounter-event"
    ))
      ? `No harmful ground area${warning}`
      : `Targeted mechanic; no ground area${warning}`;
  }
  const anchor = telegraph.anchor === "source" ? "centered on the boss" : "centered on the target";
  if (telegraph.shape === "circle") {
    return `${telegraph.radius}m radius circle ${anchor} · ${seconds(telegraph.warningMs)} warning`;
  }
  if (telegraph.shape === "cone") {
    return `${telegraph.length}m, ${telegraph.angleDegrees}° frontal cone · ${seconds(telegraph.warningMs)} warning`;
  }
  return `${telegraph.length}m × ${telegraph.width}m line from the boss · ${seconds(telegraph.warningMs)} warning`;
}

function effectFollowup(effect: EnemyAbilityEffect | undefined): string {
  if (!effect) return "Heal the affected party members after it resolves.";
  if (effect.kind === "composite") {
    return [...new Set(effect.effects.map((entry) => effectFollowup(entry)))].join(" ");
  }
  if (effect.kind === "leech") return "Limit the drain with mitigation and recover the health it steals.";
  if (effect.kind === "control") return "Stabilize the controlled player and remove the control if an available ability allows it.";
  if (effect.kind === "triggered-shout") return "Keep vulnerable party members beyond 8m of the boss and stabilize the cast victim through the control.";
  if (effect.kind === "target-aura") return "Watch the affected player's debuff and respond with healing or removal if the effect permits it.";
  if (effect.kind === "summon") return "Swap damage to the summoned adds and keep them away from vulnerable party members.";
  if (effect.kind === "heal") return "Interrupt the heal when possible; otherwise plan for the boss to recover health.";
  if (effect.kind === "call-for-help") return "Clear or control nearby enemies before this ability resolves.";
  if (effect.kind === "transform") return "Expect the boss's behavior to change after the new form appears.";
  if (effect.kind === "pull") return "Regain safe spacing after the forced movement resolves.";
  if (effect.kind === "encounter-event") return "Watch for the encounter-state change and handle the newly activated objective.";
  if (effect.kind === "aura") return "Adjust damage and healing for the aura while it remains active.";
  return "Heal the affected party members after it resolves.";
}

function describeCounterplay(attack: EnemyAttackDefinition): string {
  const telegraph = attack.telegraph;
  let movement = "";
  if (telegraph?.shape === "circle") {
    movement = telegraph.anchor === "target"
      ? "Move out of the marked circle; if it follows a player, carry it away from the group. "
      : "Leave the circle around the boss before the warning expires. ";
  } else if (telegraph?.shape === "cone") {
    movement = "Move beside or behind the boss; the tank should aim the frontal away from the party. ";
  } else if (telegraph?.shape === "line") {
    movement = "Sidestep the marked line before the warning expires. ";
  } else if (attack.effect?.kind !== "heal" && attack.interruptible !== false && (attack.castTimeMs ?? 0) > 0) {
    movement = "Interrupt the cast when possible. ";
  }
  return `${movement}${effectFollowup(attack.effect)}`.trim();
}

function describeTestInstruction(attack: EnemyAttackDefinition): string {
  const checks: string[] = [];
  if (attack.condition?.kind === "self-health-percent") {
    checks.push(`stop just above ${Math.round(attack.condition.maximum)}% health, then cross the threshold`);
  } else if (attack.initialCooldownMs) {
    checks.push(attack.initialCooldownMs[1] === 0
      ? "engage the boss and watch the opening cast"
      : `stay in combat through the ${rangeSeconds(attack.initialCooldownMs)} first-use window`);
  } else {
    checks.push("stay in combat until the mechanic becomes ready");
  }
  if (attack.telegraph) {
    checks.push(`confirm the ${attack.telegraph.shape} appears for ${seconds(attack.telegraph.warningMs)}`);
  } else if ((attack.castTimeMs ?? 0) > 0) {
    checks.push(`confirm the ${seconds(attack.castTimeMs!)} cast warning appears`);
  }
  checks.push("verify the stated target/effect when it resolves");
  return `${checks[0]}; ${checks.slice(1).join(", then ")}.`;
}

function mechanicFidelity(
  dungeon: DungeonDefinition,
  attack: EnemyAttackDefinition,
): Pick<BossMechanicGuideEntry, "fidelity" | "fidelityLabel" | "sourceDetail"> {
  if (/source-gap|fallback/i.test(attack.id)) {
    return {
      fidelity: "fallback",
      fidelityLabel: "HealerMan fallback",
      sourceDetail: "Playable behavior is supplied because the original encounter evidence is incomplete.",
    };
  }
  if (attack.source) {
    return {
      fidelity: "source",
      fidelityLabel: "Source backed",
      sourceDetail: attack.source.comment || `Server script row ${attack.source.rowId}`,
    };
  }
  if (dungeon.expansion === "runewaker") {
    return {
      fidelity: "source",
      fidelityLabel: "Source backed",
      sourceDetail: attack.spellId
        ? `RuneWaker spell ${attack.spellId}`
        : "RuneWaker spell or encounter-script import",
    };
  }
  if (/azeroth|trinity/i.test(dungeon.provenance.databaseAdapter)) {
    return {
      fidelity: "source",
      fidelityLabel: "Source backed",
      sourceDetail: attack.spellId
        ? `AzerothCore encounter import · spell ${attack.spellId}`
        : "AzerothCore encounter-script import",
    };
  }
  return {
    fidelity: "authored",
    fidelityLabel: "Gameplay authored",
    sourceDetail: attack.spellId ? `Spell ${attack.spellId}` : "HealerMan encounter definition",
  };
}

function mechanicGuide(
  dungeon: DungeonDefinition,
  entityId: string,
  sourceAttack: EnemyAttackDefinition,
  overrides: BossMechanicGuideOverrides,
): BossMechanicGuideEntry {
  const attack = normalizeEnemyAttack(sourceAttack);
  const override = overrides[bossGuideOverrideKey(dungeon.id, entityId, attack.id)] ?? {};
  return {
    id: attack.id,
    name: attack.name,
    trigger: override.trigger ?? describeCondition(attack.condition),
    timing: override.timing ?? describeTiming(attack),
    targetAndEffect: override.targetAndEffect ?? describeEffect(attack.effect, attack),
    telegraph: override.telegraph ?? describeTelegraph(attack.telegraph, attack),
    counterplay: override.counterplay ?? describeCounterplay(attack),
    testInstruction: override.testInstruction ?? describeTestInstruction(attack),
    ...mechanicFidelity(dungeon, attack),
  };
}

function normalizedName(value: string): string {
  return value.toLowerCase().replace(/\s+\d+$/, "").replace(/[^a-z0-9]+/g, "");
}

function bossEntityForObjective(
  dungeon: DungeonDefinition,
  objective: DungeonBossObjective,
): readonly [string, PopulationEntityDefinition] | undefined {
  const staticSpawn = dungeon.staticSpawns.find((spawn) => spawn.id === objective.id);
  if (staticSpawn) {
    const entity = dungeon.entities[staticSpawn.entityId];
    if (entity) return [staticSpawn.entityId, entity];
  }

  for (const group of dungeon.encounterSpawnGroups ?? []) {
    const spawn = group.spawns.find((candidate) => candidate.id === objective.id);
    if (spawn) {
      const entity = dungeon.entities[spawn.entityId];
      if (entity) return [spawn.entityId, entity];
    }
  }

  for (const pack of dungeon.roamingPacks) {
    const member = pack.members.find((candidate) => (
      `${pack.id}:${candidate.id}` === objective.id || candidate.id === objective.id
    ));
    if (member) {
      const entity = dungeon.entities[member.entityId];
      if (entity) return [member.entityId, entity];
    }
  }

  const wanted = normalizedName(objective.name);
  const named = Object.entries(dungeon.entities).find(([, entity]) => (
    entity.kind === "boss"
    && (normalizedName(entity.name) === wanted || normalizedName(entity.title) === wanted)
  ));
  if (named) return named;

  if (objective.eventOnly) {
    const related = Object.entries(dungeon.entities)
      .filter(([, entity]) => {
        const entityName = normalizedName(entity.name);
        return entityName.length >= 5 && (wanted.includes(entityName) || entityName.includes(wanted));
      })
      .sort((left, right) => {
        const leftBoss = left[1].kind === "boss" ? 1 : 0;
        const rightBoss = right[1].kind === "boss" ? 1 : 0;
        if (leftBoss !== rightBoss) return rightBoss - leftBoss;
        const leftMechanics = left[1].combat?.attacks.filter((attack) => attack.id !== "basic-attack").length ?? 0;
        const rightMechanics = right[1].combat?.attacks.filter((attack) => attack.id !== "basic-attack").length ?? 0;
        return rightMechanics - leftMechanics || left[0].localeCompare(right[0]);
      });
    if (related[0]) return related[0];
  }

  // Aggregate objectives such as Blackrock Depths' "The Seven" use a
  // synthetic objective id but retain the final source actor's exact position.
  // That representative may be typed as a mob because the objective covers a
  // multi-actor event rather than one loot-bearing boss.
  for (const group of dungeon.encounterSpawnGroups ?? []) {
    const exact = group.spawns.filter((candidate) => {
      const dx = candidate.position[0] - objective.position[0];
      const dy = candidate.position[1] - objective.position[1];
      const dz = candidate.position[2] - objective.position[2];
      return dx * dx + dy * dy + dz * dz <= 0.25 * 0.25;
    });
    const spawn = exact.find((candidate) => dungeon.entities[candidate.entityId]?.kind === "boss")
      ?? exact.find((candidate) => dungeon.entities[candidate.entityId] !== undefined);
    if (spawn) return [spawn.entityId, dungeon.entities[spawn.entityId]];
  }
  return undefined;
}

function bossGuide(
  dungeon: DungeonDefinition,
  bossId: string,
  bossName: string,
  resolved: readonly [string, PopulationEntityDefinition] | undefined,
  overrides: BossMechanicGuideOverrides,
): BossGuideEntry {
  const [entityId, entity] = resolved ?? [];
  const mechanics = entityId && entity?.combat
    ? entity.combat.attacks
      .filter((attack) => attack.id !== "basic-attack")
      .map((attack) => mechanicGuide(dungeon, entityId, attack, overrides))
    : [];
  return {
    id: bossId,
    name: bossName,
    ...(entity?.kind === "boss" ? { title: entity.title } : {}),
    ...(entityId ? { entityId } : {}),
    mechanics,
  };
}

export function buildDungeonBossGuide(
  dungeon: DungeonDefinition,
  overrides: BossMechanicGuideOverrides = {},
): DungeonBossGuide {
  const representedEntityIds = new Set<string>();
  const objectiveBosses = dungeon.bosses.map((objective) => {
    const resolved = bossEntityForObjective(dungeon, objective);
    if (resolved) representedEntityIds.add(resolved[0]);
    return bossGuide(dungeon, objective.id, objective.name, resolved, overrides);
  });
  const unplacedBosses = Object.entries(dungeon.entities)
    .filter(([entityId, entity]) => entity.kind === "boss" && !representedEntityIds.has(entityId))
    .map(([entityId, entity]) => bossGuide(dungeon, `entity:${entityId}`, entity.name, [entityId, entity], overrides));
  return {
    id: dungeon.id,
    title: dungeon.title,
    expansion: dungeon.expansion,
    bosses: [...objectiveBosses, ...unplacedBosses],
  };
}

export function buildBossGuideCatalog(
  dungeons: readonly DungeonDefinition[],
  overrides: BossMechanicGuideOverrides = {},
): readonly DungeonBossGuide[] {
  return dungeons
    .map((dungeon) => buildDungeonBossGuide(dungeon, overrides))
    .sort((left, right) => left.title.localeCompare(right.title));
}