const fs = require('fs')
const path = require('path')

const root = path.resolve(__dirname, '..')

function parseCsv(text) {
  const source = text.replace(/^\uFEFF/, '').trim()
  const records = []
  let record = []
  let value = ''
  let quoted = false
  for (let i = 0; i < source.length; i++) {
    const c = source[i]
    if (c === '"') {
      if (quoted && source[i + 1] === '"') { value += '"'; i++ }
      else quoted = !quoted
    } else if (c === ',' && !quoted) {
      record.push(value); value = ''
    } else if ((c === '\r' || c === '\n') && !quoted) {
      if (c === '\r' && source[i + 1] === '\n') i++
      record.push(value); records.push(record); record = []; value = ''
    } else value += c
  }
  record.push(value)
  records.push(record)
  const headers = records.shift()
  return records.filter(row => row.some(Boolean)).map(row => Object.fromEntries(headers.map((h, i) => [h, row[i] || ''])))
}

function csv(value) {
  return `"${String(value == null ? '' : value).replace(/"/g, '""')}"`
}

function read(name) {
  return parseCsv(fs.readFileSync(path.join(root, 'work', name), 'utf8'))
}

const frontend = read('frontend_procedure_call_inventory_20260725.csv')
const database = read('database_procedure_inventory_20260725.csv')
const normalizeName = value => String(value || '').toLocaleLowerCase()
const frontendNames = new Set(frontend.map(row => normalizeName(row.Procedure)))
const databaseNames = new Set(database.map(row => normalizeName(row.name)))
const missing = frontend
  .filter(row => !databaseNames.has(normalizeName(row.Procedure)))
  .sort((a, b) => a.Procedure.localeCompare(b.Procedure, 'zh-CN'))
const unused = database
  .filter(row => !frontendNames.has(normalizeName(row.name)))
  .sort((a, b) => a.name.localeCompare(b.name, 'zh-CN'))

const write = (name, headers, rows) => {
  const text = [headers, ...rows].map(row => row.map(csv).join(',')).join('\n') + '\n'
  fs.writeFileSync(path.join(root, 'work', name), text, 'utf8')
}

write('frontend_calls_missing_db_procedure_20260725.csv', ['Procedure', 'CallCount', 'CreateDataTypes', 'SourceFiles'], missing.map(row => [row.Procedure, row.CallCount, row.CreateDataTypes, row.SourceFiles]))
write('database_procedures_unused_by_static_frontend_20260725.csv', ['name', 'ParameterCount', 'HasWriteKeyword', 'HasExternalDependency', 'DefinitionBytes'], unused.map(row => [row.name, row.ParameterCount, row.HasWriteKeyword, row.HasExternalDependency, row.DefinitionBytes]))

console.log(JSON.stringify({ frontendProcedures: frontend.length, databaseProcedures: database.length, missing: missing.length, unused: unused.length }))