#!/usr/bin/env bun
import { existsSync, mkdirSync, readFileSync, writeFileSync } from 'fs'
import { join } from 'path'

const root = process.cwd()
const sourcePath = join(root, 'data', 'sources', 'claims', 'claims-library.json')
const outRoot = join(root, 'content_population_exports')
const clinicalRequestPath = join(outRoot, 'clinical_claims_request.csv')
mkdirSync(outRoot, { recursive: true })

const requiredFields = [
  'handle', 'skus', 'name_internal', 'heading', 'description',
  'stat_1_value', 'stat_1_name', 'stat_2_value', 'stat_2_name',
  'stat_3_value', 'stat_3_name', 'disclaimer', 'citation', 'approval_owner', 'approval_date'
]

function readJson(path: string, fallback: any = null) {
  if (!existsSync(path)) return fallback
  return JSON.parse(readFileSync(path, 'utf8').replace(/^\uFEFF/, ''))
}
function csv(rows: any[], headers: string[]) {
  const esc = (value: any) => {
    if (Array.isArray(value)) value = value.join(' | ')
    if (value === undefined || value === null) value = ''
    value = String(value)
    return /[",\n\r]/.test(value) ? `"${value.replace(/"/g, '""')}"` : value
  }
  return [headers.join(','), ...rows.map(row => headers.map(header => esc(row[header])).join(','))].join('\n') + '\n'
}
function parseClinicalRequestRows() {
  if (!existsSync(clinicalRequestPath)) return []
  const lines = readFileSync(clinicalRequestPath, 'utf8').trim().split(/\r?\n/)
  const headers = lines.shift()?.split(',') || []
  // This is a lightweight hint reader only; values containing commas are not needed for template validity.
  return lines.map(line => {
    const cells = line.split(',')
    return Object.fromEntries(headers.map((header, index) => [header, cells[index] || '']))
  })
}
function slug(value: string) {
  return String(value || '').toLowerCase().replace(/&/g, 'and').replace(/[^a-z0-9]+/g, '-').replace(/^-|-$/g, '').slice(0, 80)
}

const requestRows = parseClinicalRequestRows()
const templateClaims = requestRows.slice(0, 6).map((row: any) => ({
  handle: slug(`${row.SKU}-${row.CandidateTheme}`),
  skus: [row.SKU].filter(Boolean),
  name_internal: row.CandidateTheme || 'Internal claim name',
  heading: 'Clinically shown to...',
  description: 'Replace with source-backed approved claim copy. Do not use Feefo/customer language here.',
  stat_1_value: '',
  stat_1_name: '',
  stat_2_value: '',
  stat_2_name: '',
  stat_3_value: '',
  stat_3_name: '',
  disclaimer: '*Replace with approved disclaimer and citation context.',
  citation: {
    source_title: '',
    source_url: '',
    study_or_regulatory_reference: '',
    evidence_type: ''
  },
  approval_owner: '',
  approval_date: '',
  status: 'template_only_not_approved'
}))
const template = {
  generatedAt: new Date().toISOString(),
  instructions: [
    'Save the approved file as data/sources/claims/claims-library.json.',
    'Each claim must be source-backed and approved by the compliance/regulatory owner.',
    'Customer/Feefo language can inform benefit copy but must not be used as clinical evidence.'
  ],
  claims: templateClaims.length ? templateClaims : [{
    handle: 'example-claim-handle', skus: ['JV-EXAMPLE'], name_internal: 'Internal claim name', heading: 'Clinically shown to...', description: '',
    stat_1_value: '', stat_1_name: '', stat_2_value: '', stat_2_name: '', stat_3_value: '', stat_3_name: '', disclaimer: '',
    citation: { source_title: '', source_url: '', study_or_regulatory_reference: '', evidence_type: '' }, approval_owner: '', approval_date: '', status: 'template_only_not_approved'
  }]
}
writeFileSync(join(outRoot, 'claims_library_template.json'), JSON.stringify(template, null, 2) + '\n', 'utf8')

const library = readJson(sourcePath, null)
const issues: any[] = []
let claims: any[] = []
if (!library) {
  issues.push({ severity: 'blocked', claim: '', field: 'claims-library.json', issue: `Missing file at ${sourcePath}` })
} else if (!Array.isArray(library.claims)) {
  issues.push({ severity: 'error', claim: '', field: 'claims', issue: 'claims must be an array' })
} else {
  claims = library.claims
  const handles = new Set<string>()
  for (const claim of claims) {
    const claimName = claim.handle || claim.name_internal || '(missing handle)'
    for (const field of requiredFields) {
      const value = claim[field]
      if (value === undefined || value === null || value === '' || (Array.isArray(value) && !value.length)) {
        issues.push({ severity: 'error', claim: claimName, field, issue: 'required field missing/empty' })
      }
    }
    if (claim.handle && handles.has(claim.handle)) issues.push({ severity: 'error', claim: claimName, field: 'handle', issue: 'duplicate handle' })
    if (claim.handle) handles.add(claim.handle)
    if (claim.skus && !Array.isArray(claim.skus)) issues.push({ severity: 'error', claim: claimName, field: 'skus', issue: 'skus must be an array' })
    if (claim.citation && typeof claim.citation === 'object') {
      for (const field of ['source_title', 'source_url', 'study_or_regulatory_reference', 'evidence_type']) {
        if (!claim.citation[field]) issues.push({ severity: 'error', claim: claimName, field: `citation.${field}`, issue: 'citation field missing/empty' })
      }
    } else {
      issues.push({ severity: 'error', claim: claimName, field: 'citation', issue: 'citation must be an object' })
    }
    if (String(claim.status || '').includes('template')) issues.push({ severity: 'error', claim: claimName, field: 'status', issue: 'template claim cannot be imported as approved evidence' })
  }
}

const manifest = {
  generatedAt: new Date().toISOString(),
  source: sourcePath,
  template: join(outRoot, 'claims_library_template.json'),
  claimCount: claims.length,
  issueCount: issues.length,
  ready: claims.length > 0 && issues.length === 0,
  issues
}
writeFileSync(join(outRoot, 'claims_library_validation.json'), JSON.stringify(manifest, null, 2) + '\n', 'utf8')
writeFileSync(join(outRoot, 'claims_library_validation.csv'), csv(issues.length ? issues : [{ severity: 'pass', claim: '', field: '', issue: 'No issues' }], ['severity', 'claim', 'field', 'issue']), 'utf8')
console.log(`Claims library ready: ${manifest.ready}`)
console.log(`Claims: ${manifest.claimCount}`)
console.log(`Issues: ${manifest.issueCount}`)
if (!manifest.ready) process.exitCode = 1