/**
 * invoice_settings — résolution des paramètres de facturation d'une org
 * pour l'éditeur de factures natif.
 *
 * Stockage : JSONB `organizations.invoice_settings` (cf. migration
 * 1778800000000). Tous les champs sont optionnels, on resolve avec des
 * defaults au moment de générer un PDF.
 *
 * Convention `null` :
 *  - PATCH avec une clé à `null` explicite → reset au default sur ce champ
 *  - PATCH avec une clé absente → laisse intact
 *  - Cohérent avec brand.ts pour réduire la charge cognitive côté SPA.
 *
 * Pas de plan gating : toute org peut paramétrer sa facturation. Le gating
 * porte sur la création de facture elle-même (`canCreateInvoices`).
 *
 * Pattern : les types sont déclarés localement (pas d'import depuis
 * @rubis/shared) — cohérent avec brand.ts et les autres services. Les
 * types côté SPA (packages/shared) sont structurellement équivalents.
 */

import type Organization from '#models/organization'
import { resolveBrandTokens } from '#services/brand'

const HEX_RE = /^#[0-9a-fA-F]{6}$/u
const ISO_COUNTRY_RE = /^[A-Z]{2}$/u
const SIREN_RE = /^\d{9}$/u
const SIRET_RE = /^\d{14}$/u
const TVA_INTRA_RE = /^[A-Z]{2}[A-Z0-9]{2,18}$/u
const NAF_RE = /^\d{4}[A-Z]$/u
const IBAN_RE = /^[A-Z0-9 ]{15,40}$/u
const BIC_RE = /^[A-Z0-9]{8}([A-Z0-9]{3})?$/u

export const INVOICE_THEME_SLUGS = ['classique', 'moderne', 'minimal', 'elegant'] as const
export type InvoiceThemeSlug = (typeof INVOICE_THEME_SLUGS)[number]

export interface InvoiceIssuer {
  companyName?: string | null
  addressLine1?: string | null
  addressLine2?: string | null
  addressZip?: string | null
  addressCity?: string | null
  addressCountry?: string | null
  siren?: string | null
  siret?: string | null
  tvaIntra?: string | null
  rcs?: string | null
  capital?: string | null
  formeJuridique?: string | null
  naf?: string | null
  contactEmail?: string | null
  contactPhone?: string | null
}

export interface InvoiceRib {
  iban?: string | null
  bic?: string | null
  bankName?: string | null
}

/** Shape brute du JSONB `organizations.invoice_settings`. */
export interface InvoiceSettings {
  themeSlug?: InvoiceThemeSlug
  accentColor?: string | null
  numeroPrefix?: string | null
  numeroNextSeq?: number | null
  numeroPadding?: number | null
  paymentTermsDays?: number | null
  penaltyRateText?: string | null
  escompteText?: string | null
  footerLegalText?: string | null
  issuer?: InvoiceIssuer | null
  rib?: InvoiceRib | null
}

/** Settings résolus — ce que les templates PDF consomment. */
export interface ResolvedInvoiceSettings {
  themeSlug: InvoiceThemeSlug
  accentColor: string
  numeroPrefix: string
  numeroNextSeq: number
  numeroPadding: number
  paymentTermsDays: number
  penaltyRateText: string
  escompteText: string
  footerLegalText: string
  issuer: Required<{ [K in keyof InvoiceIssuer]: string | null }>
  rib: Required<{ [K in keyof InvoiceRib]: string | null }>
}

/** Defaults publics — texte légal aligné sur les exigences du Code de commerce. */
export const DEFAULT_PENALTY_RATE_TEXT =
  "En cas de retard de paiement, des pénalités de retard sont exigibles au taux annuel équivalent à trois fois le taux d'intérêt légal. Une indemnité forfaitaire pour frais de recouvrement de 40 € s'applique également (art. D441-5 du Code de commerce)."

export const DEFAULT_ESCOMPTE_TEXT = "Pas d'escompte consenti pour paiement anticipé."

export const DEFAULT_PAYMENT_TERMS_DAYS = 30
export const DEFAULT_NUMERO_PADDING = 4
export const DEFAULT_THEME_SLUG: InvoiceThemeSlug = 'classique'

/**
 * Résout les settings effectifs d'une org pour générer un PDF.
 *
 * - `accentColor` : settings → brand.primaryColor → rubis #9F1239
 * - `issuer.companyName` : settings → org.name
 * - `issuer.siret` : settings → org.siret
 * - autres : defaults applicatifs
 */
export function resolveInvoiceSettings(org: Organization): ResolvedInvoiceSettings {
  const settings = (org.invoiceSettings ?? null) as InvoiceSettings | null
  const brand = resolveBrandTokens(org)

  return {
    themeSlug: settings?.themeSlug ?? DEFAULT_THEME_SLUG,
    accentColor: settings?.accentColor ?? brand.primary,
    numeroPrefix: settings?.numeroPrefix ?? '',
    numeroNextSeq: settings?.numeroNextSeq ?? 1,
    numeroPadding: settings?.numeroPadding ?? DEFAULT_NUMERO_PADDING,
    paymentTermsDays: settings?.paymentTermsDays ?? DEFAULT_PAYMENT_TERMS_DAYS,
    penaltyRateText: settings?.penaltyRateText ?? DEFAULT_PENALTY_RATE_TEXT,
    escompteText: settings?.escompteText ?? DEFAULT_ESCOMPTE_TEXT,
    footerLegalText: settings?.footerLegalText ?? '',
    issuer: {
      companyName: settings?.issuer?.companyName ?? org.name ?? null,
      addressLine1: settings?.issuer?.addressLine1 ?? null,
      addressLine2: settings?.issuer?.addressLine2 ?? null,
      addressZip: settings?.issuer?.addressZip ?? null,
      addressCity: settings?.issuer?.addressCity ?? null,
      addressCountry: settings?.issuer?.addressCountry ?? 'FR',
      siren: settings?.issuer?.siren ?? null,
      siret: settings?.issuer?.siret ?? org.siret ?? null,
      tvaIntra: settings?.issuer?.tvaIntra ?? null,
      rcs: settings?.issuer?.rcs ?? null,
      capital: settings?.issuer?.capital ?? null,
      formeJuridique: settings?.issuer?.formeJuridique ?? null,
      naf: settings?.issuer?.naf ?? null,
      contactEmail: settings?.issuer?.contactEmail ?? null,
      contactPhone: settings?.issuer?.contactPhone ?? null,
    },
    rib: {
      iban: settings?.rib?.iban ?? null,
      bic: settings?.rib?.bic ?? null,
      bankName: settings?.rib?.bankName ?? null,
    },
  }
}

/**
 * Merge un patch dans les settings existants — pattern identique à
 * `mergeBrandSettings` : `null` explicite supprime le champ, `undefined`
 * laisse intact. `issuer` et `rib` sont mergés en deep partial.
 */
export function mergeInvoiceSettings(
  existing: InvoiceSettings | null,
  patch: Partial<InvoiceSettings>
): InvoiceSettings {
  const next: InvoiceSettings = { ...(existing ?? {}) }

  for (const [key, value] of Object.entries(patch) as [keyof InvoiceSettings, unknown][]) {
    if (value === null) {
      delete next[key]
      continue
    }
    if (value === undefined) continue

    if (key === 'issuer') {
      const existingIssuer = (existing?.issuer ?? {}) as InvoiceIssuer
      const patchIssuer = value as InvoiceIssuer
      const merged: InvoiceIssuer = { ...existingIssuer }
      for (const [k, v] of Object.entries(patchIssuer) as [keyof InvoiceIssuer, unknown][]) {
        if (v === null) {
          delete merged[k]
        } else if (v !== undefined) {
          ;(merged as Record<string, unknown>)[k] = v
        }
      }
      next.issuer = merged
      continue
    }

    if (key === 'rib') {
      const existingRib = (existing?.rib ?? {}) as InvoiceRib
      const patchRib = value as InvoiceRib
      const merged: InvoiceRib = { ...existingRib }
      for (const [k, v] of Object.entries(patchRib) as [keyof InvoiceRib, unknown][]) {
        if (v === null) {
          delete merged[k]
        } else if (v !== undefined) {
          ;(merged as Record<string, unknown>)[k] = v
        }
      }
      next.rib = merged
      continue
    }

    ;(next as Record<string, unknown>)[key] = value
  }

  return next
}

/**
 * Valide un patch InvoiceSettings — retourne le premier message d'erreur,
 * ou null si tout est OK. Vérifications minimales en complément de Vine
 * côté validator (les regex sont dupliquées pour blinder le service en
 * cas d'appel direct hors HTTP).
 */
export function validateInvoiceSettings(patch: Partial<InvoiceSettings>): string | null {
  if (patch.themeSlug !== undefined && patch.themeSlug !== null) {
    if (!INVOICE_THEME_SLUGS.includes(patch.themeSlug)) {
      return `invalid_theme: doit être l'un de ${INVOICE_THEME_SLUGS.join(', ')}`
    }
  }
  if (patch.accentColor !== undefined && patch.accentColor !== null) {
    if (!HEX_RE.test(patch.accentColor)) {
      return 'invalid_accent_color: format #RRGGBB attendu'
    }
  }
  if (patch.numeroPadding !== undefined && patch.numeroPadding !== null) {
    if (!Number.isInteger(patch.numeroPadding) || patch.numeroPadding < 1 || patch.numeroPadding > 10) {
      return 'invalid_numero_padding: entier entre 1 et 10'
    }
  }
  if (patch.numeroNextSeq !== undefined && patch.numeroNextSeq !== null) {
    if (!Number.isInteger(patch.numeroNextSeq) || patch.numeroNextSeq < 1) {
      return 'invalid_numero_next_seq: entier ≥ 1'
    }
  }
  if (patch.paymentTermsDays !== undefined && patch.paymentTermsDays !== null) {
    if (
      !Number.isInteger(patch.paymentTermsDays) ||
      patch.paymentTermsDays < 0 ||
      patch.paymentTermsDays > 365
    ) {
      return 'invalid_payment_terms_days: entier entre 0 et 365'
    }
  }

  if (patch.issuer) {
    const { issuer } = patch
    if (issuer.addressCountry && !ISO_COUNTRY_RE.test(issuer.addressCountry)) {
      return 'invalid_issuer.address_country: code ISO 2 lettres'
    }
    if (issuer.siren && !SIREN_RE.test(issuer.siren)) {
      return 'invalid_issuer.siren: 9 chiffres requis'
    }
    if (issuer.siret && !SIRET_RE.test(issuer.siret)) {
      return 'invalid_issuer.siret: 14 chiffres requis'
    }
    if (issuer.tvaIntra && !TVA_INTRA_RE.test(issuer.tvaIntra)) {
      return 'invalid_issuer.tva_intra: format UE invalide (ex. FR12345678901)'
    }
    if (issuer.naf && !NAF_RE.test(issuer.naf)) {
      return 'invalid_issuer.naf: format NAF/APE invalide (ex. 6201Z)'
    }
  }

  if (patch.rib) {
    const { rib } = patch
    if (rib.iban && !IBAN_RE.test(rib.iban)) {
      return 'invalid_rib.iban: IBAN invalide'
    }
    if (rib.bic && !BIC_RE.test(rib.bic)) {
      return 'invalid_rib.bic: BIC/SWIFT invalide (8 ou 11 caractères)'
    }
  }

  return null
}

/** Normalise un IBAN : majuscules + suppression des espaces. */
export function normalizeIban(iban: string): string {
  return iban.replace(/\s+/g, '').toUpperCase()
}