/**
 * Issue #438: Enchant (#52) One-Shot Visual Playback Verification Suite
 *
 * 1.13c Ground Truth Invariants:
 * 1. One-Shot Visual: Enchant cast overlay (`enchant`, FireEnchant.dc6) plays 17 frames once (`loop: false`).
 * 2. Natural Dissolution: After 17 animation frames (~27 logic ticks), the overlay naturally expires and
 *    is removed from `engine.overlays`.
 * 3. Buff Persistence: Player's enchant buff (`player.enchantTicks`, `player.enchantDamage`,
 *    `player.enchantAttackRatingPercent`) remains active for its full duration (e.g. 3600+ ticks)
 *    even after the visual overlay has expired.
 */
import { describe, expect, it } from 'vitest'
import { GameEngine, type EngineInput } from '../../../src/server/engine/engine.ts'
import { castSkill } from '../../../src/server/scene/skill-caster.ts'
import { DEMO_SKILLS } from '../../../src/common/data/demo-data.ts'

const DEFAULT_INPUT: EngineInput = {
  movement: { x: 0, y: 0 },
  attacking: false,
  pickingUp: false,
  talking: false,
  digits: [],
  saving: false,
  loading: false,
}

describe('Issue #438: Enchant (#52) One-Shot Visual Overlay', () => {
  it('spawns enchant overlay with loop: false which expires after 17 frames while buff remains active', () => {
    const engine = new GameEngine(
      { widthPx: 1000, heightPx: 1000, overlap: () => 0 },
      { spawn: { x: 300, y: 300 }, stats: [], questDefs: [], npcDefs: [], skills: DEMO_SKILLS } as any,
    )
    const player = engine.world.player
    player.x = 300
    player.y = 300
    player.mana = 500
    player.cooldown = 0

    const statusEl = { textContent: '' } as HTMLElement
    const dummyRuntime = {
      walkable: { isWalkable: () => true },
      collision: { isWalkable: () => true },
    } as any

    const castOk = castSkill(52, 300, 300, {
      engine,
      runtime: dummyRuntime,
      hudManager: null,
      status: statusEl,
    })
    expect(castOk).toBe(true)

    // Verify buff is active on player
    expect(player.enchantTicks).toBeGreaterThan(1000)
    expect(player.enchantDamage).toBeDefined()
    expect(player.enchantAttackRatingPercent).toBeDefined()

    // Verify overlay was spawned with loop: false
    const enchantOverlay = engine.overlays.find(ov => ov.overlayName === 'enchant')
    expect(enchantOverlay).toBeDefined()
    expect(enchantOverlay!.loop).toBe(false)
    expect(enchantOverlay!.maxFrames).toBe(17)

    // Tick engine for 20 ticks: overlay is still playing (< 17 frames)
    for (let t = 0; t < 20; t++) {
      engine.tick(DEFAULT_INPUT)
    }
    expect(enchantOverlay!.expired).toBe(false)
    expect(engine.overlays.some(ov => ov.overlayName === 'enchant')).toBe(true)

    // Tick engine for another 15 ticks (total 35 ticks > 27 ticks required for 17 frames at 16/25 frame rate)
    for (let t = 0; t < 15; t++) {
      engine.tick(DEFAULT_INPUT)
    }

    // Verify overlay is now naturally expired and cleaned up from engine.overlays
    expect(enchantOverlay!.expired).toBe(true)
    const activeEnchantOverlay = engine.overlays.find(ov => ov.overlayName === 'enchant' && !ov.expired)
    expect(activeEnchantOverlay).toBeUndefined()

    // Verify player buff is STILL ACTIVE and unexpired!
    expect(player.enchantTicks).toBeGreaterThan(1000)
    expect(player.enchantDamage).toBeDefined()
    expect(player.enchantAttackRatingPercent).toBeDefined()
  })
})