#!/usr/bin/env node
// Prints the image-edit request for the hero keyframe: the product from the photo, unchanged, placed in the mood's set.
// It does not call any API.
// Usage:
//   node scripts/build-keyframe-input.mjs --photo product.jpg --product "matte black over-ear headphones" --mood dark-luxe
//     [--aspect 16:9|9:16|1:1] [--size standard|tall|tiny] [--label-text "EXACT TEXT" | --unbranded] [--colour "tangerine orange"] [--draft] [--out keyframe.json]
// --photo takes a local file (embedded as a data URI) or a public https URL.
import { readFileSync, writeFileSync, existsSync } from 'node:fs'
import { dirname, join, extname } from 'node:path'
import { fileURLToPath } from 'node:url'

const root = join(dirname(fileURLToPath(import.meta.url)), '..')
const usage = 'Usage: node scripts/build-keyframe-input.mjs --photo <file or https URL> --product "short description" --mood dark-luxe|glass-glow|bright-clean|colour-pop [--aspect 16:9|9:16|1:1] [--size standard|tall|tiny] [--label-text "EXACT TEXT" | --unbranded] [--colour "name or #hex"] [--draft] [--out keyframe.json]'
const VALUE_FLAGS = new Set(['photo', 'product', 'mood', 'aspect', 'size', 'label-text', 'colour', 'out'])
const SWITCHES = new Set(['unbranded', 'draft'])
const fail = (message) => { console.error(`${message}\n${usage}`); process.exit(1) }

const options = {}
const args = process.argv.slice(2)
for (let i = 0; i < args.length; i += 1) {
  const arg = args[i]
  if (!arg.startsWith('--')) fail(`Unexpected argument "${arg}".`)
  const key = arg.slice(2)
  if (SWITCHES.has(key)) { options[key] = true; continue }
  if (!VALUE_FLAGS.has(key)) fail(`Unknown flag --${key}.`)
  const value = args[i + 1]
  if (value === undefined || value.startsWith('--')) fail(`--${key} needs a value.`)
  options[key] = value
  i += 1
}
for (const key of ['photo', 'product', 'mood']) if (!options[key]) fail(`--${key} is required.`)

const presets = JSON.parse(readFileSync(join(root, 'assets/reveal-presets.json'), 'utf8'))
const settings = JSON.parse(readFileSync(join(root, 'assets/generation-input.json'), 'utf8')).keyframe
const mood = presets.moods[options.mood]
if (!mood) fail(`Unknown mood "${options.mood}". Use one of: ${Object.keys(presets.moods).join(', ')}.`)
const aspect = options.aspect ?? '16:9'
const size = options.size ?? 'standard'
const sizes = Object.keys(presets.sizes).filter((key) => !key.startsWith('_'))
if (!sizes.includes(size)) fail(`Unknown size "${size}". Use one of: ${sizes.join(', ')} (tall for bottles and shoes standing up, tiny for rings and earbuds).`)
if (!presets.sizes[size][aspect]) fail(`Unknown aspect "${aspect}". Use 16:9, 9:16 or 1:1.`)
for (const [kind, name] of [['moods', options.mood], ['sizes', size]]) {
  const tested = presets.tested?.[kind]?.[name]
  if (tested && !tested.includes('(the preview)') && !tested.includes('keyframes')) console.error(`Note: ${kind.slice(0, -1)} "${name}" so far: ${tested}. Make a --draft keyframe first and check it beside the photo.`)
}
if (options['label-text'] && options.unbranded) fail('Use --label-text or --unbranded, not both.')
const colour = options.colour ?? 'tangerine orange'
if (!/^(#[0-9a-f]{6}|[a-z][a-z -]{1,30})$/i.test(colour)) fail('--colour must be a colour name (letters, spaces, dashes) or a #rrggbb hex value.')
if (options.mood !== 'colour-pop' && options.colour) fail('--colour only applies to --mood colour-pop.')

const MIME = { '.jpg': 'image/jpeg', '.jpeg': 'image/jpeg', '.png': 'image/png', '.webp': 'image/webp' }
let photo = options.photo
if (!/^https:\/\//.test(photo)) {
  if (!existsSync(photo)) fail(`Photo not found: ${photo}`)
  const mime = MIME[extname(photo).toLowerCase()]
  if (!mime) fail('The product photo must be a still image (.jpg, .png or .webp). For a video, export one clear frame first.')
  photo = `data:${mime};base64,${readFileSync(photo).toString('base64')}`
}

const product = options.product.trim()
const labelClause = options['label-text']
  ? `, and the printed text reads exactly "${options['label-text'].trim()}", in the same place, size and typeface`
  : options.unbranded
    ? ', and it stays plain and unbranded: no logo, no monogram, no lettering anywhere on it'
    : ', and the same logos and printed text exactly as in the photo'
const template = readFileSync(join(root, 'assets/prompt-template.md'), 'utf8')
const section = template.match(/## Keyframe\s+([\s\S]*?)(?=\n## |$)/)?.[1]?.trim()
if (!section) fail('assets/prompt-template.md is missing its "## Keyframe" section.')
const values = {
  mood_name: mood.name,
  product,
  label_clause: labelClause,
  scene: mood.scene.replace('{{colour}}', () => colour),
  framing: presets.sizes[size][aspect],
}
// Replacer functions keep any "$" in the user's text literal.
const prompt = section.replace(/\{\{(\w+)\}\}/g, (_, name) => values[name] ?? '').replace(/\s{2,}/g, ' ')
const input = {
  ...settings.input,
  ...(options.draft ? { quality: settings.draft_quality } : {}),
  image_size: presets.keyframe_size[aspect],
  image_urls: [photo],
  prompt,
}
const output = JSON.stringify({ model: settings.model, input }, null, 2)
if (options.out) {
  writeFileSync(options.out, output)
  console.log(`Wrote the keyframe request to ${options.out}`)
} else console.log(output)