import fs from 'node:fs'
import path from 'node:path'

const source = JSON.parse(fs.readFileSync('contracts/fields/kbx.fields.json', 'utf8'))
const known = new Set(source.fields.map(x => x.key))
const deprecated = new Map(source.fields.filter(x => x.deprecated).map(x => [x.key, x.replacementKey]))
const files = []
function walk(dir) {
  if (!fs.existsSync(dir)) return
  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
    const full = path.join(dir, entry.name)
    if (entry.isDirectory()) walk(full)
    else if (/\.(ts|vue)$/.test(entry.name)) files.push(full)
  }
}
walk('apps/web/src')

const occurrences = []
const patterns = [
  /\bfield\s*:\s*['"]([A-Za-z][A-Za-z0-9]*)['"]/g,
  /kbxImportField\(\s*['"]([A-Za-z][A-Za-z0-9]*)['"]\s*\)/g,
]
for (const file of files) {
  const text = fs.readFileSync(file, 'utf8')
  for (const pattern of patterns) {
    for (const match of text.matchAll(pattern)) {
      const key = match[1]
      occurrences.push({ file, key, canonical: known.has(key), deprecated: deprecated.has(key), replacementKey: deprecated.get(key) ?? null })
    }
  }
}
const counts = new Map()
for (const x of occurrences) counts.set(x.key, (counts.get(x.key) ?? 0) + 1)
const unique = [...counts.keys()].sort()
const canonical = unique.filter(x => known.has(x))
const unknown = unique.filter(x => !known.has(x))
const candidates = unknown
  .map(key => ({ key, occurrences: counts.get(key) ?? 0 }))
  .filter(x => x.occurrences >= 2)
  .sort((a,b) => b.occurrences-a.occurrences || a.key.localeCompare(b.key))
const deprecatedUses = occurrences.filter(x => x.deprecated)
const report = {
  dictionaryVersion: source.version,
  canonicalFieldCount: known.size,
  scannedFiles: files.length,
  fieldOccurrences: occurrences.length,
  uniqueFieldKeysObserved: unique.length,
  canonicalKeysUsed: canonical,
  localOrUnknownKeys: unknown,
  promotionCandidates: candidates,
  deprecatedUses,
  note: 'Unknown keys are not automatically errors: local read-model fields may remain local. Repeated business concepts are promotion candidates for the canonical dictionary.',
}
fs.writeFileSync('generated/field-adoption-report.json', JSON.stringify(report, null, 2) + '\n')
console.log(`field adoption report: canonical-used=${canonical.length}, local/unknown=${unknown.length}, promotion-candidates=${candidates.length}, deprecated-uses=${deprecatedUses.length}`)