/**
 * Online quote confirmation — the offer counterpart of the contract signing
 * portal. Shared by quote/send.post.ts (link creation + mail CTA) and the
 * PUBLIC routes /api/public/confirm/<token>/* (page data, confirm, documents).
 *
 * Lifecycle: quote send with `confirmation.enabled` → createSigningRequest()
 * with kind 'quote' (contractSigningDb.ts — same table/store as contract
 * signing, superseding per kind) + the exact offer PDF on disk + a CTA button
 * in the quote e-mail → the lead opens /confirm/<token>, reads the offer and
 * confirms with name/company/e-mail + declarations → finalizeQuoteConfirmation():
 * the offer PDF gets a "Angebotsbestätigung" page appended (pdf-lib), is stored,
 * attached to the record (Strapi), written into offer_conditions.quote.confirmation,
 * mailed to the confirmer + info@logyou.de and logged as an activity.
 *
 * Public-route writes use the service token (config.api.idempieretoken).
 */
import { PDFDocument, StandardFonts, rgb } from 'pdf-lib'
import { BRAND } from './quotePdf'
import { attachToStrapi } from '../inbox/strapiAttach'
import { patchOfferConditionsSection } from './offerConditions'
import { APP_BASE_URL } from '../emailVerification'
import { logContactActivity, strapiPublicFileUrl } from './contactActivity'
import {
  NOTIFY_EMAIL, brandedEmail, escapeHtml, formatDateHuman, formatDateTimeHuman, mailTransport, recordLink
} from './contractSigning'
import {
  type SigningRequest, type SigningDocumentMeta,
  readSigningFile, writeSigningFile, sha256Hex, markSigningRequestSigned
} from './contractSigningDb'

export const confirmLink = (token: string) => `${APP_BASE_URL}/confirm/${token}`
export const confirmDocumentLink = (token: string, key: string) => `${APP_BASE_URL}/api/public/confirm/${token}/document/${key}`

/** Expiry of a confirmation link = the quote's validity (end of that day). */
export const resolveConfirmationExpiry = (validDays: number): string => {
  const n = Number.isFinite(validDays) && validDays > 0 ? Math.min(validDays, 365) : 7
  const d = new Date()
  d.setDate(d.getDate() + n)
  d.setHours(23, 59, 59, 0)
  return d.toISOString()
}

/** CTA block inserted into the quote e-mail when online confirmation is on. */
export const confirmCtaHtml = (language: string, link: string, expiresAt: string) => {
  const en = language === 'en'
  const title = en ? 'View the quote online' : 'Angebot online ansehen'
  const text = en
    ? 'The button opens your quote for reading and download. Clicking it does <strong>not</strong> accept anything yet — if you decide to accept, you do so afterwards on that page in a separate, clearly marked step (no reply e-mail needed). You will then receive a confirmation copy immediately.'
    : 'Über den Button öffnen Sie Ihr Angebot zum Lesen und Herunterladen. Mit dem Klick bestätigen Sie <strong>noch nichts</strong> — wenn Sie das Angebot annehmen möchten, tun Sie das anschließend auf der Seite in einem separaten, klar gekennzeichneten Schritt (ganz ohne Antwort-E-Mail). Sie erhalten dann sofort eine Bestätigungskopie.'
  const btn = en ? 'Open quote' : 'Angebot öffnen'
  const note = en ? 'Viewing only — clicking does not accept the quote.' : 'Nur ansehen — der Klick ist unverbindlich.'
  const valid = en ? `This link is valid until ${formatDateHuman(expiresAt, 'en')}.` : `Der Link ist gültig bis ${formatDateHuman(expiresAt, 'de')}.`
  return `
            <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background-color:#eef4fb;border-left:4px solid ${BRAND.navy};border-radius:4px;margin-top:6px;">
              <tr>
                <td style="padding:16px 18px;color:#33414E;font-size:13px;">
                  <div style="font-weight:bold;font-size:14px;margin-bottom:6px;">&#128196;&nbsp; ${title}</div>
                  <div>${text}</div>
                  <p style="text-align:center;margin:16px 0 6px 0;"><a href="${link}" style="display:inline-block;padding:12px 26px;background:${BRAND.orange};color:#fff;text-decoration:none;border-radius:6px;font-weight:bold;">${btn}</a></p>
                  <div style="font-size:11px;color:#5a6b7c;text-align:center;">${note}<br>${valid}</div>
                </td>
              </tr>
            </table>`
}

export const confirmCtaText = (language: string, link: string, expiresAt: string) => language === 'en'
  ? `\n\nView the quote online (accepting it there is optional and a separate step): ${link}\n(valid until ${formatDateHuman(expiresAt, 'en')})`
  : `\n\nAngebot online ansehen (die Annahme ist dort optional und ein separater Schritt): ${link}\n(gültig bis ${formatDateHuman(expiresAt, 'de')})`

/**
 * Declarations the confirmer ticks — SERVER-side wording so the confirmation
 * page always records the canonical text. Never pre-selected.
 */
export const confirmationAcceptanceTexts = (language: string, req: SigningRequest) => {
  const en = language === 'en'
  const validDays = Number(req.payload?.meta?.validDays) || 7
  const offer = req.documents.find((d) => d.key === 'offer')
  const name = offer?.filename || (en ? 'the quote' : 'das Angebot')
  return [
    {
      key: 'offer',
      required: true,
      text: en
        ? `I have read the quote (${name}) and accept it with binding effect. The listed prices and conditions apply; the quote was valid for ${validDays} days.`
        : `Ich habe das Angebot (${name}) gelesen und nehme es verbindlich an. Es gelten die darin genannten Preise und Konditionen; das Angebot war ${validDays} Tage gültig.`
    },
    {
      key: 'contract',
      required: true,
      text: en
        ? 'I understand that the fulfillment agreement and its annexes (T&C, data processing agreement) will follow for signature and that services start after the agreement is signed.'
        : 'Mir ist bekannt, dass der Fulfillment-Rahmenvertrag inkl. Anlagen (AGB, Auftragsverarbeitungsvertrag) zur Unterschrift folgt und die Leistung nach Vertragsunterzeichnung beginnt.'
    },
    {
      key: 'authorized',
      required: true,
      text: en
        ? 'I am authorised to accept this quote on behalf of the named company.'
        : 'Ich bin berechtigt, dieses Angebot im Namen des genannten Unternehmens anzunehmen.'
    }
  ]
}

export interface ConfirmerInput {
  company: string
  contactName: string
  position?: string
  email: string
  phone?: string
  message?: string
}

export const validateConfirmer = (s: ConfirmerInput, language: string): string => {
  const en = language === 'en'
  const req = (v: any) => String(v || '').trim() !== ''
  if (!req(s.company)) return en ? 'Company is required' : 'Firma ist ein Pflichtfeld'
  if (!req(s.contactName)) return en ? 'Name is required' : 'Name ist ein Pflichtfeld'
  if (!/.+@.+\..+/.test(String(s.email || '').trim())) return en ? 'A valid e-mail is required' : 'Eine gültige E-Mail-Adresse ist erforderlich'
  return ''
}

// pdf-lib standard fonts are WinAnsi — map the few typographic chars we use.
const winAnsi = (s: any) => String(s ?? '')
  .replace(/→/g, '->').replace(/—/g, '-').replace(/–/g, '-')
  .replace(/…/g, '...').replace(/[‘’]/g, "'").replace(/[“”„]/g, '"')
  .replace(/[^\x00-\xFF€]/g, '?')

const wrapText = (text: string, font: any, size: number, maxWidth: number): string[] => {
  const out: string[] = []
  for (const para of String(text || '').split('\n')) {
    const words = para.split(/\s+/).filter(Boolean)
    if (!words.length) { out.push(''); continue }
    let line = ''
    for (const w of words) {
      const probe = line ? `${line} ${w}` : w
      if (font.widthOfTextAtSize(probe, size) <= maxWidth) { line = probe; continue }
      if (line) out.push(line)
      line = w
    }
    if (line) out.push(line)
  }
  return out
}

/**
 * The "confirmed offer": the exact offer PDF the customer saw + one appended
 * confirmation page (who, when, from where, hash of the offer, declarations).
 */
export const buildConfirmedOfferPdf = async (offerBuffer: Buffer, opts: {
  language: string
  offerFilename: string
  offerSha256: string
  confirmer: ConfirmerInput
  confirmedAt: string
  ip: string
  userAgent: string
  token: string
  acceptances: Array<{ key: string; text: string; acceptedAt: string }>
}): Promise<Buffer> => {
  const en = opts.language === 'en'
  const pdf = await PDFDocument.load(offerBuffer, { ignoreEncryption: true })
  const font = await pdf.embedFont(StandardFonts.Helvetica)
  const bold = await pdf.embedFont(StandardFonts.HelveticaBold)
  const page = pdf.addPage([595.28, 841.89])
  const navy = rgb(0x1c / 255, 0x32 / 255, 0x4b / 255)
  const orange = rgb(0xf1 / 255, 0x59 / 255, 0x24 / 255)
  const grey = rgb(0x5a / 255, 0x6b / 255, 0x7c / 255)
  const text = rgb(0x33 / 255, 0x41 / 255, 0x4e / 255)
  const M = 48
  const W = 595.28 - 2 * M
  let y = 841.89 - 60

  page.drawRectangle({ x: 0, y: 841.89 - 22, width: 595.28, height: 22, color: navy })
  page.drawRectangle({ x: 0, y: 841.89 - 25, width: 595.28, height: 3, color: orange })
  page.drawText(winAnsi(en ? 'Quote acceptance' : 'Angebotsbestätigung'), { x: M, y, size: 20, font: bold, color: navy })
  y -= 18
  page.drawText(winAnsi(en ? 'Binding acceptance via the LogYou online portal' : 'Verbindliche Annahme über das LogYou Online-Portal'), { x: M, y, size: 10, font, color: grey })
  y -= 30

  const rows: Array<[string, string]> = [
    [en ? 'Quote' : 'Angebot', opts.offerFilename],
    [en ? 'Company' : 'Firma', opts.confirmer.company],
    [en ? 'Accepted by' : 'Angenommen von', `${opts.confirmer.contactName}${opts.confirmer.position ? `, ${opts.confirmer.position}` : ''}`],
    [en ? 'E-mail' : 'E-Mail', opts.confirmer.email],
    [en ? 'Phone' : 'Telefon', opts.confirmer.phone || '-'],
    [en ? 'Accepted on' : 'Angenommen am', formatDateTimeHuman(opts.confirmedAt, opts.language)],
    [en ? 'IP address' : 'IP-Adresse', opts.ip],
    [en ? 'Browser' : 'Browser', opts.userAgent.slice(0, 90)],
    [en ? 'Link token' : 'Link-Token', opts.token.slice(0, 16) + '…'],
    [en ? 'SHA-256 (quote)' : 'SHA-256 (Angebot)', opts.offerSha256]
  ]
  for (const [k, v] of rows) {
    page.drawText(winAnsi(k), { x: M, y, size: 9.5, font: bold, color: text })
    const lines = wrapText(winAnsi(v), font, 9.5, W - 150)
    for (const ln of lines) {
      page.drawText(ln, { x: M + 150, y, size: 9.5, font, color: text })
      y -= 13
    }
    y -= 3
  }

  if (opts.confirmer.message) {
    y -= 8
    page.drawText(winAnsi(en ? 'Message from the customer' : 'Nachricht des Kunden'), { x: M, y, size: 10.5, font: bold, color: navy })
    y -= 15
    for (const ln of wrapText(winAnsi(opts.confirmer.message), font, 9.5, W)) {
      page.drawText(ln, { x: M, y, size: 9.5, font, color: text }); y -= 13
    }
  }

  y -= 12
  page.drawText(winAnsi(en ? 'Declarations confirmed' : 'Bestätigte Erklärungen'), { x: M, y, size: 10.5, font: bold, color: navy })
  y -= 15
  for (const a of opts.acceptances) {
    const lines = wrapText(winAnsi(a.text), font, 9, W - 14)
    page.drawText('x', { x: M, y: y + 1, size: 8, font: bold, color: orange })
    for (const ln of lines) {
      page.drawText(ln, { x: M + 14, y, size: 9, font, color: text }); y -= 12
    }
    page.drawText(winAnsi(`${en ? 'confirmed at' : 'bestätigt am'} ${formatDateTimeHuman(a.acceptedAt, opts.language)}`), { x: M + 14, y, size: 7.5, font, color: grey })
    y -= 16
  }

  page.drawText(winAnsi(en
    ? 'This page was generated automatically by the LogYou quote portal and forms part of the accepted quote.'
    : 'Diese Seite wurde automatisch vom LogYou Angebotsportal erzeugt und ist Bestandteil des angenommenen Angebots.'), { x: M, y: 40, size: 7.5, font, color: grey })

  return Buffer.from(await pdf.save())
}

const attachmentsFor = (req: SigningRequest, docs: SigningDocumentMeta[]) => docs
  .map((d) => {
    const content = readSigningFile(req.token, d.filename)
    return content ? { filename: d.filename, content, contentType: 'application/pdf' } : null
  })
  .filter(Boolean) as any[]

/**
 * Confirm: build the confirmed offer PDF, store + attach + notify + log.
 * Throws only when the confirmed PDF cannot be produced/stored — everything
 * downstream is fail-soft and reported in `warnings`.
 */
export const finalizeQuoteConfirmation = async (event: any, req: SigningRequest, confirmer: ConfirmerInput, meta: { ip: string; userAgent: string }, acceptances: Array<{ key: string; text: string; acceptedAt: string }> = []) => {
  const warnings: string[] = []
  const language = req.language
  const en = language === 'en'
  const confirmedAt = new Date().toISOString()

  const offerMeta = req.documents.find((d) => d.key === 'offer') || req.documents[0]
  if (!offerMeta) throw new Error('no offer document on request')
  const offerBuffer = readSigningFile(req.token, offerMeta.filename)
  if (!offerBuffer) throw new Error('offer file missing')

  const confirmedFilename = offerMeta.filename.replace(/\.pdf$/i, en ? '_confirmed.pdf' : '_bestaetigt.pdf')
  const confirmedBuffer = await buildConfirmedOfferPdf(offerBuffer, {
    language, offerFilename: offerMeta.filename, offerSha256: offerMeta.sha256, confirmer, confirmedAt,
    ip: meta.ip, userAgent: meta.userAgent, token: req.token, acceptances
  })
  writeSigningFile(req.token, confirmedFilename, confirmedBuffer)

  const confirmedMeta: SigningDocumentMeta = {
    key: 'confirmed',
    title: en ? 'Accepted quote (confirmation)' : 'Angenommenes Angebot (Bestätigung)',
    filename: confirmedFilename,
    sha256: sha256Hex(confirmedBuffer),
    size: confirmedBuffer.length,
    signed: true
  }
  const confirmedDocuments: SigningDocumentMeta[] = [confirmedMeta, ...req.documents]
  const confirmerRecord = { ...confirmer, confirmedAt, ip: meta.ip, userAgent: meta.userAgent, acceptances }
  markSigningRequestSigned(req.token, confirmerRecord, confirmedDocuments, confirmedAt)

  const config: any = useRuntimeConfig()
  const serviceToken: string = config.api?.idempieretoken || ''

  // 1) Attach the confirmed offer to the record.
  let attachedUrl = ''
  try {
    if (!(req.recordId > 0)) throw new Error('no record id')
    const up = await attachToStrapi(event, serviceToken, {
      tableName: req.source === 'lead' ? 'Lead_User' : 'C_BPartner',
      recordId: req.recordId,
      recordUu: req.recordUu || undefined,
      buffer: confirmedBuffer,
      filename: confirmedFilename,
      mimeType: 'application/pdf'
    })
    attachedUrl = strapiPublicFileUrl(up.fileUrl)
  } catch (err: any) {
    console.error('[Confirm] attach confirmed offer failed:', err?.message || err)
    warnings.push('attach')
  }

  // 2) Persist the confirmation on the record's quote conditions.
  try {
    if (!(req.recordId > 0)) throw new Error('no record id')
    await patchOfferConditionsSection(event, serviceToken, req.source, req.recordId, 'quote', {
      confirmation: {
        confirmedAt,
        name: confirmer.contactName,
        company: confirmer.company,
        position: confirmer.position || '',
        email: confirmer.email,
        phone: confirmer.phone || '',
        message: confirmer.message || '',
        filename: confirmedFilename,
        offerFilename: offerMeta.filename,
        offerSha256: offerMeta.sha256,
        token: req.token,
        ip: meta.ip,
        acceptances
      }
    })
  } catch (err: any) {
    console.error('[Confirm] offer_conditions save skipped:', err?.message || err)
    warnings.push('conditions')
  }

  // 3) Activity on the record (fail-soft inside the helper).
  try {
    const docs = [
      { title: confirmedMeta.title, url: attachedUrl || confirmDocumentLink(req.token, 'confirmed') },
      { title: en ? 'Quote (as sent)' : 'Angebot (wie versendet)', url: confirmDocumentLink(req.token, 'offer') }
    ]
    const created = await logContactActivity(event, serviceToken, {
      source: req.source,
      recordId: req.recordId,
      type: 'EM',
      contactEmail: req.email,
      description: en ? `Quote accepted online: ${confirmer.company}` : `Angebot online bestätigt: ${confirmer.company}`,
      comments: en
        ? `${confirmer.contactName}${confirmer.position ? ` (${confirmer.position})` : ''}, ${confirmer.company}, accepted the quote ${offerMeta.filename} on ${formatDateTimeHuman(confirmedAt, 'en')} via the online portal.\nE-mail: ${confirmer.email}${confirmer.phone ? ` · Phone: ${confirmer.phone}` : ''}${confirmer.message ? `\n\nMessage: ${confirmer.message}` : ''}`
        : `${confirmer.contactName}${confirmer.position ? ` (${confirmer.position})` : ''}, ${confirmer.company}, hat das Angebot ${offerMeta.filename} am ${formatDateTimeHuman(confirmedAt, 'de')} über das Online-Portal verbindlich angenommen.\nE-Mail: ${confirmer.email}${confirmer.phone ? ` · Telefon: ${confirmer.phone}` : ''}${confirmer.message ? `\n\nNachricht: ${confirmer.message}` : ''}`,
      documents: docs
    })
    if (!created) warnings.push('activity')
  } catch (err: any) {
    console.error('[Confirm] activity failed:', err?.message || err)
    warnings.push('activity')
  }

  // 4) Confirmation copy to the customer.
  const attachments = attachmentsFor(req, confirmedDocuments)
  try {
    await mailTransport().sendMail({
      from: NOTIFY_EMAIL,
      to: confirmer.email,
      subject: en ? `Your accepted quote – ${confirmer.company}` : `Ihr angenommenes Angebot – ${confirmer.company}`,
      text: en
        ? `Dear ${confirmer.contactName},\n\nthank you — you accepted our quote on ${formatDateTimeHuman(confirmedAt, 'en')}. The quote and your confirmation are attached.\n\nNext step: we will send you the fulfillment agreement for digital signature and get in touch within one business day to plan your onboarding.\n\nBest regards\nYour LogYou team`
        : `Guten Tag ${confirmer.contactName},\n\nvielen Dank — Sie haben unser Angebot am ${formatDateTimeHuman(confirmedAt, 'de')} verbindlich angenommen. Das Angebot und Ihre Bestätigung finden Sie im Anhang.\n\nNächster Schritt: Wir senden Ihnen den Fulfillment-Rahmenvertrag zur digitalen Unterschrift und melden uns innerhalb von einem Werktag, um Ihr Onboarding zu planen.\n\nMit freundlichen Grüßen\nIhr LogYou Team`,
      html: brandedEmail(
        en ? 'Your accepted quote' : 'Ihr angenommenes Angebot',
        en
          ? `Dear ${escapeHtml(confirmer.contactName)},<br><br>thank you — you accepted our quote on <strong>${formatDateTimeHuman(confirmedAt, 'en')}</strong>. The quote and your confirmation are attached to this e-mail.<br><br><strong>Next step:</strong> we will send you the fulfillment agreement for digital signature and get in touch within one business day to plan your onboarding.<br><br>Best regards<br>Your LogYou team`
          : `Guten Tag ${escapeHtml(confirmer.contactName)},<br><br>vielen Dank — Sie haben unser Angebot am <strong>${formatDateTimeHuman(confirmedAt, 'de')}</strong> verbindlich angenommen. Das Angebot und Ihre Bestätigung finden Sie im Anhang dieser E-Mail.<br><br><strong>Nächster Schritt:</strong> Wir senden Ihnen den Fulfillment-Rahmenvertrag zur digitalen Unterschrift und melden uns innerhalb von einem Werktag, um Ihr Onboarding zu planen.<br><br>Mit freundlichen Grüßen<br>Ihr LogYou Team`,
        en ? 'This email was sent automatically.' : 'Diese E-Mail wurde automatisch versendet.'
      ),
      attachments
    })
  } catch (err: any) {
    console.error('[Confirm] customer copy mail failed:', err?.message || err)
    warnings.push('mail-customer')
  }

  // 5) Internal notification with record link.
  try {
    const link = recordLink(req.source, req.recordId)
    const rows = [
      ['Firma', confirmer.company], ['Name', confirmer.contactName], ['Position', confirmer.position || '—'],
      ['E-Mail', confirmer.email], ['Telefon', confirmer.phone || '—'],
      ['Angebot', offerMeta.filename], ['Bestätigt am', formatDateTimeHuman(confirmedAt, 'de')], ['IP', meta.ip], ['Browser', meta.userAgent]
    ]
    const table = `<table cellpadding="0" cellspacing="0" style="width:100%;border-collapse:collapse;margin:12px 0;border:1px solid #e5e7eb;border-radius:6px;font-size:13px;">${rows.map(([k, v]) => `<tr><td style="padding:7px 12px;border-bottom:1px solid #e5e7eb;font-weight:600;width:150px;background:#f9fafb;">${escapeHtml(k)}</td><td style="padding:7px 12px;border-bottom:1px solid #e5e7eb;">${escapeHtml(v)}</td></tr>`).join('')}</table>`
    await mailTransport().sendMail({
      from: NOTIFY_EMAIL,
      to: NOTIFY_EMAIL,
      subject: `✅ Angebot online bestätigt – ${confirmer.company}`,
      text: `${confirmer.company} (${confirmer.contactName}) hat das Angebot ${offerMeta.filename} am ${formatDateTimeHuman(confirmedAt, 'de')} online verbindlich angenommen.${confirmer.message ? `\n\nNachricht: ${confirmer.message}` : ''}\n\nDatensatz: ${link}`,
      html: brandedEmail(
        'Angebot online bestätigt',
        `<strong>${escapeHtml(confirmer.company)}</strong> (${escapeHtml(confirmer.contactName)}) hat das Angebot verbindlich angenommen.${table}${confirmer.message ? `<blockquote style="margin:14px 0;padding:10px 14px;border-left:3px solid ${BRAND.orange};background:#f7f8fa;">${escapeHtml(confirmer.message).replace(/\n/g, '<br>')}</blockquote>` : ''}Die Bestätigung ist angehängt und wurde am ${req.source === 'lead' ? 'Lead' : 'Geschäftspartner'} als Anhang und Aktivität gespeichert. Nächster Schritt: Vertrag senden.<br><br><a href="${link}" style="display:inline-block;padding:10px 22px;background:${BRAND.navy};color:#fff;text-decoration:none;border-radius:6px;font-weight:bold;">${req.source === 'lead' ? 'Lead öffnen' : 'Geschäftspartner öffnen'}</a>${warnings.length ? `<p style="color:#b23c11;font-size:12px;margin-top:14px;">Hinweis: folgende Schritte sind fehlgeschlagen und müssen manuell geprüft werden: ${warnings.join(', ')}</p>` : ''}`,
        'Automatische Benachrichtigung des LogShip-Angebotsportals.'
      ),
      attachments
    })
  } catch (err: any) {
    console.error('[Confirm] internal notification mail failed:', err?.message || err)
    warnings.push('mail-internal')
  }

  return { confirmedAt, confirmedDocuments, confirmedFilename, warnings }
}