/**
 * Lane I — the slot inventory.
 *
 * A "slot" is a named place in the scene where a custom GLB may replace the
 * procedural mesh the game builds today. Slot ids are a closed set on purpose:
 * the editor (lane J) lists them, the manifest keys on them, and an unknown key
 * in a hand-edited manifest should be reported rather than silently ignored.
 *
 * Kept free of `three` imports so the validator can be node-tested headlessly.
 */

export const SLOT_IDS = [
  'blob.body',
  'blob.face',
  'ghost.body',
  'cannon.base',
  'cannon.barrel',
  'machine.plate',
  'machine.boot',
  'machine.bucket',
  'machine.arch',
  'machine.belt',
  'machine.fan',
  'machine.seesaw',
  'course.scenery.cereal',
  'course.scenery.block',
  'course.finish',
  'course.tunnel',
  'course.tramp',
  'fx.puddle',
] as const

export type SlotId = (typeof SLOT_IDS)[number]

const SLOT_SET: ReadonlySet<string> = new Set<string>(SLOT_IDS)

export function isSlotId(v: unknown): v is SlotId {
  return typeof v === 'string' && SLOT_SET.has(v)
}

/** Plain-language labels for the editor UI (lane J reads this). */
export const SLOT_LABELS: Record<SlotId, string> = {
  'blob.body': 'Blobbo body (paintable)',
  'blob.face': 'Blobbo eyes',
  'ghost.body': 'Ghost racer',
  'cannon.base': 'Paint cannon base',
  'cannon.barrel': 'Paint cannon barrel',
  'machine.plate': 'Pressure plate',
  'machine.boot': 'Spring boot',
  'machine.bucket': 'Paint bucket',
  'machine.arch': 'Bubble arch',
  'machine.belt': 'Conveyor belt',
  'machine.fan': 'Fan',
  'machine.seesaw': 'See-saw plank',
  'course.scenery.cereal': 'Giant cereal box',
  'course.scenery.block': 'Purple block',
  'course.finish': 'Finish pad',
  'course.tunnel': 'MINI tunnel roof',
  'course.tramp': 'Trampoline / gap launcher',
  'fx.puddle': 'Paint puddle',
}

/**
 * Slots whose replacement is constrained beyond "looks different". Surfaced in
 * the editor so John sees the rule at the moment he drops a file on the slot.
 */
export const SLOT_NOTES: Partial<Record<SlotId, string>> = {
  'blob.body':
    'Must be ONE mesh with ONE material and clean 0..1 UVs — the paint is stamped ' +
    'through those UVs. Auto-resized to the 1.0u body; manifest scale is ignored here.',
  'ghost.body':
    'Copied from blob.body automatically unless you set this slot; materials are ' +
    'forced translucent.',
  'machine.boot': 'Model it standing on the floor, origin at the base — it shakes about its origin.',
  'machine.bucket': 'Origin at the TIPPING EDGE, pours toward +X, up axis +Y.',
  'machine.belt': 'Model the belt slab only; the moving chevrons stay procedural.',
  'machine.fan': 'Face +Z. The blades stay procedural so they keep spinning.',
  'machine.seesaw': 'Plank only, long axis along X, origin at the plank centre.',
  'machine.plate': 'Frame only — the pressed pad stays procedural so it can light up.',
  'cannon.base': 'The stand only; the barrel is a separate slot because it aims every step.',
  'cannon.barrel': 'The tube only, pointing +Z — the aiming pivot stays procedural.',
  'course.finish': 'Fill the 18 x 1.2 x 6 pad volume — its collider never moves.',
  'course.tunnel':
    'Roof slab only (7 x 0.3 x 14). Keep the underside FLAT at the model\'s bottom: ' +
    'clearance under it is what a MINI blob squeezes through, and the collider does not change.',
  'course.tramp': 'Fill the pad volume; the launch impulse is unaffected by the model.',
}

/**
 * Slots the game builds ONCE. Everything else may be instanced many times over
 * (nine puddles, six cannons, every machine) and each instance gets its own
 * clone of the asset at its own pose — see docs/ASSET-SLOTS.md.
 */
export const SINGLE_INSTANCE_SLOTS: ReadonlySet<string> = new Set<string>([
  'blob.body', 'blob.face', 'ghost.body',
  'course.finish', 'course.tunnel', 'course.scenery.cereal', 'course.scenery.block',
])