botfights/frontend/src/game/arcade/projectiles.ts

import type { GameObj, PosComp, RectComp, AnchorComp, ColorComp, OpacityComp, ZComp } from 'kaplay'
import type { KaplayInstance, FighterInstance } from './types'
import {
  FIREBALL_SPEED, FIREBALL_WIDTH, FIREBALL_HEIGHT, FIREBALL_DAMAGE,
  HURTBOX_WIDTH, HURTBOX_HEIGHT, CROUCH_HURTBOX_HEIGHT,
  HITSTUN_SPECIAL, BLOCKSTUN_SPECIAL, CHIP_DAMAGE_RATIO,
  MAX_PROJECTILES, STAGE_LEFT, STAGE_RIGHT,
} from './constants'
import type { HitResult } from './combat'

type ProjectileObj = GameObj<PosComp | RectComp | AnchorComp | ColorComp | OpacityComp | ZComp>

interface Projectile {
  obj: ProjectileObj
  owner: 1 | 2
  speed: number
  damage: number
  alive: boolean
}

const projectiles: Projectile[] = []

/**
 * Spawn a fireball projectile from the attacker's position.
 */
export function spawnFireball(
  k: KaplayInstance,
  fighter: FighterInstance,
  safeColor: (color: string) => ReturnType<KaplayInstance['Color']['fromHex']>,
): void {
  // Count existing projectiles for this player
  const existing = projectiles.filter(p => p.owner === fighter.player && p.alive).length
  if (existing >= MAX_PROJECTILES) return

  const dir = fighter.physics.facingRight ? 1 : -1
  const x = fighter.obj.pos.x + 40 * dir
  const y = fighter.obj.pos.y - 40

  // Outer glow
  k.add([
    k.rect(FIREBALL_WIDTH + 6, FIREBALL_HEIGHT + 6),
    k.pos(x, y),
    k.anchor('center'),
    k.color(safeColor('#ff880044')),
    k.opacity(0.3),
    k.z(14),
    `fireball_glow_${fighter.player}`,
    { speed: FIREBALL_SPEED * dir, owner: fighter.player },
  ])

  const obj = k.add([
    k.rect(FIREBALL_WIDTH, FIREBALL_HEIGHT),
    k.pos(x, y),
    k.anchor('center'),
    k.color(safeColor('#ff6600')),
    k.opacity(1),
    k.z(15),
    `fireball_${fighter.player}`,
  ]) as unknown as ProjectileObj

  const projectile: Projectile = {
    obj,
    owner: fighter.player,
    speed: FIREBALL_SPEED * dir,
    damage: FIREBALL_DAMAGE,
    alive: true,
  }
  projectiles.push(projectile)
}

/**
 * Update all projectiles. Called each frame from the game loop.
 * Returns hit results for any projectile that connected.
 */
export function updateProjectiles(
  k: KaplayInstance,
  fighters: [FighterInstance, FighterInstance],
  dt: number,
): { target: FighterInstance; result: HitResult }[] {
  const hits: { target: FighterInstance; result: HitResult }[] = []

  // Update glow positions to follow their fireballs
  for (const player of [1, 2] as const) {
    const glows = k.get(`fireball_glow_${player}`) as unknown as ProjectileObj[]
    for (const glow of glows) {
      const spd = (glow as any).speed as number
      glow.pos.x += spd * dt
      if (glow.pos.x < STAGE_LEFT - 50 || glow.pos.x > STAGE_RIGHT + 50) {
        glow.destroy()
      }
    }
  }

  for (const proj of projectiles) {
    if (!proj.alive) continue

    // Move
    proj.obj.pos.x += proj.speed * dt

    // Off-screen cleanup
    if (proj.obj.pos.x < STAGE_LEFT - 50 || proj.obj.pos.x > STAGE_RIGHT + 50) {
      proj.obj.destroy()
      proj.alive = false
      continue
    }

    // Check collision with opponent
    const target = fighters.find(f => f.player !== proj.owner)
    if (!target) continue

    const isCrouching = target.combat.state === 'crouching' || target.combat.state === 'blocking'
    const hurtH = isCrouching ? CROUCH_HURTBOX_HEIGHT : HURTBOX_HEIGHT
    const tLeft = target.obj.pos.x - HURTBOX_WIDTH / 2
    const tRight = target.obj.pos.x + HURTBOX_WIDTH / 2
    const tTop = target.obj.pos.y - hurtH
    const tBottom = target.obj.pos.y

    const pLeft = proj.obj.pos.x - FIREBALL_WIDTH / 2
    const pRight = proj.obj.pos.x + FIREBALL_WIDTH / 2
    const pTop = proj.obj.pos.y - FIREBALL_HEIGHT / 2
    const pBottom = proj.obj.pos.y + FIREBALL_HEIGHT / 2

    if (pRight >= tLeft && pLeft <= tRight && pBottom >= tTop && pTop <= tBottom) {
      const isBlocking = target.combat.state === 'blocking' && target.physics.grounded
      const result: HitResult = isBlocking
        ? {
            type: 'blocked',
            damage: Math.round(proj.damage * CHIP_DAMAGE_RATIO),
            hitstun: 0,
            blockstun: BLOCKSTUN_SPECIAL,
            knockbackX: 60,
            knockbackY: 0,
            hitbox: { offsetX: 0, offsetY: 0, width: FIREBALL_WIDTH, height: FIREBALL_HEIGHT, damage: proj.damage, hitstun: HITSTUN_SPECIAL, blockstun: BLOCKSTUN_SPECIAL, knockbackX: 120, knockbackY: 0, activeFrames: [0, 0] },
          }
        : {
            type: 'hit',
            damage: proj.damage,
            hitstun: HITSTUN_SPECIAL,
            blockstun: 0,
            knockbackX: 120,
            knockbackY: -80,
            hitbox: { offsetX: 0, offsetY: 0, width: FIREBALL_WIDTH, height: FIREBALL_HEIGHT, damage: proj.damage, hitstun: HITSTUN_SPECIAL, blockstun: BLOCKSTUN_SPECIAL, knockbackX: 120, knockbackY: -80, activeFrames: [0, 0] },
          }

      hits.push({ target, result })
      proj.obj.destroy()
      proj.alive = false
    }
  }

  // Clean up dead projectiles
  for (let i = projectiles.length - 1; i >= 0; i--) {
    if (!projectiles[i].alive) projectiles.splice(i, 1)
  }

  return hits
}

/**
 * Destroy all projectiles (round reset).
 */
export function clearAllProjectiles(k: KaplayInstance): void {
  for (const proj of projectiles) {
    if (proj.alive && proj.obj.exists()) {
      proj.obj.destroy()
    }
  }
  projectiles.length = 0

  // Clean glow objects
  for (const player of [1, 2]) {
    for (const glow of k.get(`fireball_glow_${player}`)) {
      glow.destroy()
    }
  }
}