/**
 * Optical-techniques register — named lens-and-camera patterns that produce
 * specific recognizable looks (Joey 3.0 Worldbuilder). PURE and deterministic:
 * no I/O, no Date, no Math.random.
 *
 * Each technique is a complete optical recipe (vantage + lens + the physical
 * ingredient that sells the look) plus the constraint that keeps it from
 * collapsing — the same shape as the VFX register (`vfx-register.ts`), applied
 * to glass instead of effects. FOV degrees follow the discrete anchor ladder
 * in `cinematography.ts` (`FOV_ANCHORS`).
 */

export interface OpticalTechnique {
  id: string;
  label: string;
  /** The prompt-ready optical recipe (vantage → lens → ingredient). */
  phrase: string;
  /** The constraint that keeps the technique from breaking. */
  constraint: string;
}

const TECHNIQUES: OpticalTechnique[] = [
  {
    id: 'voyeur',
    label: 'Voyeur / long-lens observation',
    phrase:
      'framed from a distant anchored vantage on an 8° (350mm) extreme long lens, a foreground obstruction — '
      + 'a wall edge, a pillar, a branch, a curtain — thrown fully out of focus and covering roughly a quarter of the '
      + 'frame, suspended atmosphere stacked in the air between camera and subject',
    constraint: 'the vantage stays anchored across the sequence — never zoom in on a voyeur shot; only the obstruction may change',
  },
  {
    id: 'press-box',
    label: 'Broadcast press-box',
    phrase:
      'an 8° (350mm) tele lens from a fixed distant vantage, handheld with a small one-to-two-centimeter hunting '
      + 'tremor, the operator hunting the action like a live sports broadcast',
    constraint: 'the vantage never moves; only the hunt does',
  },
  {
    id: 'foreground-wide',
    label: 'Foreground-loaded wide (macro-in-a-wide)',
    phrase:
      'an 84° (22mm) wide lens from a low angle inches from the hero object, the camera almost touching it — the '
      + 'object rendered huge in the foreground while the background pushes back into deep space',
    constraint: 'keep the hero object tack-sharp and anchored; the depth does the drama, not the distortion',
  },
  {
    id: 'wide-portrait',
    label: 'Wide portrait',
    phrase:
      'a close face rendered on a 63° (32mm) wide FOV at a normal working distance — the face stays the anchor of '
      + 'the frame while the room around it remains legible and in focus',
    constraint: 'no distortion-stretch on the features; the width is for the world, not the face',
  },
  {
    id: 'atmosphere-column',
    label: 'Compressed atmosphere column',
    phrase:
      'a 12° (190mm) long lens stacking the air on itself — a thick column of suspended particulate visible between '
      + 'the operator and the subject, compressed into a wall of atmosphere the subject reads through',
    constraint: 'name the particulate and tie it to the scene (dust, heat waver, mist); the column only reads when the air is real',
  },
];

export const OPTICAL_TECHNIQUES: Record<string, OpticalTechnique> = Object.fromEntries(
  TECHNIQUES.map((technique) => [technique.id, technique]),
);

export const OPTICAL_TECHNIQUE_IDS: string[] = TECHNIQUES.map((technique) => technique.id);

/**
 * The optical-technique line for `id`: the recipe + its holding constraint.
 * Throws on an unknown id (no silent fallback).
 */
export function opticalTechniqueLine(id: string): string {
  const technique = OPTICAL_TECHNIQUES[id];
  if (!technique) {
    throw new Error(`unknown optical technique: ${id}. Expected one of ${OPTICAL_TECHNIQUE_IDS.join(', ')}.`);
  }
  return `${technique.phrase}. ${capitalize(technique.constraint)}.`;
}

function capitalize(text: string): string {
  return text.length === 0 ? text : `${text[0]!.toUpperCase()}${text.slice(1)}`;
}