export const ASSET_FAMILIES = [
  'color',
  'diffuse',
  'roughness',
  'normal',
  'metalness',
  'height',
  'opacity',
  'orm',
  'ao',
] as const

export type AssetFamily = typeof ASSET_FAMILIES[number]

const ASSET_FAMILY_BY_KEY = new Map(ASSET_FAMILIES.map((family) => [family.toLowerCase(), family]))
const FORBIDDEN_ASSET_FAMILY_ALIASES: ReadonlyMap<string, AssetFamily> = new Map([
  ['basecolor', 'color'],
  ['base_color', 'color'],
  ['normalopengl', 'normal'],
  ['normal_opengl', 'normal'],
  ['metallic', 'metalness'],
  ['occlusionroughnessmetallic', 'roughness'],
  ['occlusion_roughness_metallic', 'roughness'],
])

const EXPORTED_SUFFIX_ALIASES: Array<{ suffix: string; family: AssetFamily }> = [
  { suffix: 'occlusionroughnessmetallic', family: 'orm' },
  { suffix: 'occlusion_roughness_metallic', family: 'orm' },
  { suffix: 'normal_opengl', family: 'normal' },
  { suffix: 'normalopengl', family: 'normal' },
  { suffix: 'base_color', family: 'color' },
  { suffix: 'basecolor', family: 'color' },
  { suffix: 'mixed_ao', family: 'ao' },
  { suffix: 'metallic', family: 'metalness' },
  { suffix: 'roughness', family: 'roughness' },
  { suffix: 'normal', family: 'normal' },
  { suffix: 'height', family: 'height' },
  { suffix: 'opacity', family: 'opacity' },
  { suffix: 'diffuse', family: 'diffuse' },
  { suffix: 'color', family: 'color' },
]

export function getAssetFamily(value: string): AssetFamily | undefined {
  return ASSET_FAMILY_BY_KEY.get(value.toLowerCase())
}

export function getForbiddenAssetFamilyAlias(value: string): AssetFamily | undefined {
  return FORBIDDEN_ASSET_FAMILY_ALIASES.get(value.toLowerCase())
}

function getFileStem(filename: string) {
  return filename.replace(/\.[^.]+$/, '')
}

function getFileExtension(filename: string) {
  return filename.split('.').pop()?.toLowerCase() || ''
}

function normalizeTargetName(target: string) {
  return target
    .trim()
    .replace(/[\s-]+/g, '_')
    .replace(/_+/g, '_')
    .replace(/^_+|_+$/g, '')
}

function buildTextureFilename(family: AssetFamily, target: string, extension: string) {
  const normalizedTarget = normalizeTargetName(target)
  return `${family}${normalizedTarget ? `_${normalizedTarget}` : ''}.${extension}`
}

function getExportedTextureAlias(stem: string) {
  const lowerStem = stem.toLowerCase()

  for (const alias of EXPORTED_SUFFIX_ALIASES) {
    const lowerSuffix = alias.suffix.toLowerCase()
    if (lowerStem === lowerSuffix) {
      return { family: alias.family, target: '' }
    }

    if (lowerStem.endsWith(`_${lowerSuffix}`)) {
      return {
        family: alias.family,
        target: stem.slice(0, -lowerSuffix.length - 1),
      }
    }
  }

  return null
}

export function normalizeTextureFilename(filename: string) {
  const stem = getFileStem(filename)
  const extension = getFileExtension(filename)
  const [prefix, ...targetParts] = stem.split('_')
  const family = getAssetFamily(prefix)

  if (family) {
    return buildTextureFilename(family, targetParts.join('_'), extension)
  }

  const exportedAlias = getExportedTextureAlias(stem)
  if (exportedAlias) {
    return buildTextureFilename(exportedAlias.family, exportedAlias.target, extension)
  }

  return null
}

export function getTextureNamingError(filename: string) {
  const stem = getFileStem(filename)
  const [prefix, ...targetParts] = stem.split('_')
  const family = getAssetFamily(prefix)
  const extension = getFileExtension(filename)

  if (normalizeTextureFilename(filename)) return null

  if (family && targetParts.every(Boolean)) return null

  const aliasSuggestion = getForbiddenAssetFamilyAlias(prefix)

  if (aliasSuggestion && targetParts.every(Boolean)) {
    const target = targetParts.join('_')
    return `Convention invalide : ${filename}. Utilisez ${aliasSuggestion}_${target}.${extension} pour cibler "${target}", ou ${aliasSuggestion}.${extension} pour tout le modele.`
  }

  const reversedParts = stem.split('_')
  const reversedFamily = reversedParts.length > 1 ? getAssetFamily(reversedParts[reversedParts.length - 1]) : undefined
  const reversedAliasSuggestion = reversedParts.length > 1
    ? getForbiddenAssetFamilyAlias(reversedParts[reversedParts.length - 1])
    : undefined

  if (reversedFamily) {
    const target = reversedParts.slice(0, -1).join('_')
    return `Convention invalide : ${filename}. Utilisez ${reversedFamily}_${target}.${extension} pour cibler "${target}", ou ${reversedFamily}.${extension} pour tout le modele.`
  }

  if (reversedAliasSuggestion) {
    const target = reversedParts.slice(0, -1).join('_')
    return `Convention invalide : ${filename}. Utilisez ${reversedAliasSuggestion}_${target}.${extension} pour cibler "${target}", ou ${reversedAliasSuggestion}.${extension} pour tout le modele.`
  }

  return `Asset inconnu : ${filename}. Familles autorisees : ${formatAssetFamilies()}. Utilisez asset.png pour tout le modele ou asset_objet.png pour cibler un objet.`
}

export function formatAssetFamilies() {
  return ASSET_FAMILIES.join(', ')
}