// EnergyNetWatch county permit example. Node.js 18+, no dependencies.
// Run on your own machine/server; never embed an API key in a web page.
import { mkdir, writeFile } from 'node:fs/promises'
import { resolve } from 'node:path'
import { pathToFileURL } from 'node:url'

export async function fetchCountyPermits({ apiKey, county = 'Ward', maxPages = 5, fetchImpl = fetch }) {
  if (!apiKey) throw new Error('Set ENERGYNETWATCH_API_KEY in your environment; do not put it in this file.')
  if (!county.trim()) throw new Error('County is required.')
  if (!Number.isInteger(maxPages) || maxPages < 1 || maxPages > 10) throw new Error('maxPages must be 1–10.')
  const rows = [], requests = [], seen = new Set()
  let page = 1, total, first
  for (let attempt = 0; attempt < maxPages; attempt++) {
    const url = new URL('https://api.energynetwatch.com/api/public/permits')
    url.search = new URLSearchParams({ state: 'TX', county, days: '90', page: String(page), limit: '25' }).toString()
    const response = await fetchImpl(url, {
      headers: { 'X-API-Key': apiKey, Accept: 'application/json' },
      redirect: 'error', signal: AbortSignal.timeout(30_000),
    })
    const requestId = response.headers.get('x-request-id')
    if (!response.ok) {
      const reasons = { 401: 'Check the key.', 402: 'Check available units.', 403: 'Check permits:read scope and access.', 429: 'Check rate/quota headers before trying again.' }
      throw new Error(`HTTP ${response.status}; request ${requestId || 'unavailable'}. ${reasons[response.status] || 'Stop and inspect the request.'} No automatic retry.`)
    }
    const body = await response.json(), data = body.data, p = data?.pagination, req = data?.meta?.request
    if (!body.success || !Array.isArray(data?.permits) || !p || p.page !== page || p.limit !== 25 ||
        !Number.isInteger(p.total) || p.total < 0 || p.returned !== data.permits.length ||
        req?.state !== 'TX' || req?.days !== 90 || !req?.canonicalCounty ||
        req.canonicalCounty.toLowerCase() !== county.toLowerCase() || req.countyBasis !== 'well_api_county_with_w1_fallback') {
      throw new Error('Unexpected response or county scope. Stop; do not present a partial export as complete.')
    }
    if (total !== undefined && (p.total !== total || JSON.stringify(data.countWindow) !== JSON.stringify(first.countWindow))) {
      throw new Error('Results changed during pagination. Stop and review before spending units on another run.')
    }
    total = p.total
    first ??= data
    requests.push({ url: url.toString(), requestId, returned: p.returned, generatedAt: data.meta.generatedAt, freshness: data.meta.freshness })
    for (const row of data.permits) {
      const identity = row.id ?? (row.permit_number != null && row.api12 != null ? `${row.permit_number}|${row.api12}` : null)
      if (identity == null || seen.has(String(identity))) throw new Error('Missing or repeated record identity. Stop; do not silently drop records.')
      seen.add(String(identity)); rows.push(row)
    }
    if (p.hasMore === false && p.nextPage === null) {
      if (rows.length !== total) throw new Error('Collected row count does not match pagination.total.')
      return { retrievedAt: new Date().toISOString(), complete: true, total, estimatedUnits: requests.length * 6,
        query: { state: 'TX', county: req.canonicalCounty, countyFips: req.countyFips, days: 90, dateField: 'issue_date', limit: 25 },
        countWindow: first.countWindow, requests, permits: rows }
    }
    if (p.hasMore !== true || p.nextPage !== page + 1 || p.returned === 0) throw new Error('Invalid next page; stopping without retry.')
    page = p.nextPage
  }
  throw new Error(`Stopped at ${maxPages} pages (${maxPages * 6} estimated units). No complete export. Review the budget before increasing maxPages.`)
}

// Quote every cell and neutralize spreadsheet-formula prefixes. Raw JSON is unchanged.
export function csvCell(value) {
  let text = value == null ? '' : String(value)
  if (/^[\s]*[=+\-@\t\r\n]/.test(text)) text = "'" + text
  return '"' + text.replaceAll('"', '""') + '"'
}
export function toCsv(rows) {
  const fields = ['permit_number', 'api12', 'operator_name', 'county_name', 'issue_date', 'spud_date']
  return [fields.map(csvCell).join(','), ...rows.map(row => fields.map(field => csvCell(row[field])).join(','))].join('\r\n') + '\r\n'
}

async function main() {
  const result = await fetchCountyPermits({ apiKey: process.env.ENERGYNETWATCH_API_KEY, county: process.env.ENW_COUNTY || 'Ward' })
  const directory = resolve(process.argv[2] || `county-permits-${Date.now()}`)
  await mkdir(directory, { recursive: true })
  await writeFile(resolve(directory, 'permits.json'), JSON.stringify(result, null, 2), { flag: 'wx' })
  await writeFile(resolve(directory, 'permits.csv'), toCsv(result.permits), { flag: 'wx' })
  console.log(`${result.total} records; ${result.requests.length} requests; ${result.estimatedUnits} estimated API units. Files: ${directory}`)
}
if (process.argv[1] && import.meta.url === pathToFileURL(resolve(process.argv[1])).href) {
  main().catch(error => { console.error(error.message); process.exitCode = 1 })
}