import type { Metadata } from "next"
import { displayFileName } from "@/lib/drive/display-file-name"
import { parseDriveSegments } from "@/lib/drive/drive-url"

export type SuiteApp = "mail" | "drive" | "contacts" | "suite"

/** Separator between page segment and product name in document titles. */
export const SUITE_TITLE_SEP = " - "

export const MAIL_INBOX_DOCUMENT_TITLE = `Boîte mail${SUITE_TITLE_SEP}Ultimail`

const DESCRIPTIONS: Record<SuiteApp, string> = {
  mail: "Client mail Ultimail — suite souveraine",
  drive: "Stockage de fichiers UltiDrive — suite Ultimail",
  contacts: "Carnet d'adresses — Ulti Suite",
  suite: "Ultimail, UltiDrive et contacts — interface suite unifiée",
}

const APP_LABELS: Record<SuiteApp, string> = {
  mail: "Ultimail",
  drive: "UltiDrive",
  contacts: "Ulti Suite",
  suite: "Ulti Suite",
}

const ICONS: Record<Exclude<SuiteApp, "suite">, Metadata["icons"]> = {
  mail: {
    icon: [
      { url: "/brand/ultimail-header-icon.png", sizes: "109x109", type: "image/png" },
      { url: "/icon.png", sizes: "32x32", type: "image/png" },
    ],
    apple: [{ url: "/brand/ultimail-header-icon.png", sizes: "180x180", type: "image/png" }],
    shortcut: "/brand/ultimail-header-icon.png",
  },
  drive: {
    icon: [
      { url: "/ultidrive-mark.svg", type: "image/svg+xml" },
      { url: "/drive/favicon-32.png", sizes: "32x32", type: "image/png" },
      { url: "/drive/favicon-16.png", sizes: "16x16", type: "image/png" },
    ],
    apple: [{ url: "/drive/apple-touch-icon.png", sizes: "180x180", type: "image/png" }],
    shortcut: "/ultidrive-mark.svg",
  },
  contacts: {
    icon: [
      { url: "/contacts-mark.svg", type: "image/svg+xml" },
      { url: "/icon.png", sizes: "32x32", type: "image/png" },
    ],
    apple: [{ url: "/contacts-mark.svg", type: "image/svg+xml" }],
    shortcut: "/contacts-mark.svg",
  },
}

type PageMetadataOptions = {
  app: SuiteApp
  /** Full document title (no suffix added). */
  title?: string
  /** Short segment only — parent layout `title.template` adds the product suffix. */
  titleSegment?: string
  description?: string
  /** When true with `title`, use `title` as the full document title. */
  absoluteTitle?: boolean
}

export function formatSuiteDocumentTitle(segment: string, app: SuiteApp): string {
  return `${segment}${SUITE_TITLE_SEP}${APP_LABELS[app]}`
}

export function truncateSubjectForTitle(subject: string, maxLen = 48): string {
  const clean = subject.replace(/\s+/g, " ").trim()
  if (!clean) return ""
  if (clean.length <= maxLen) return clean
  return `${clean.slice(0, maxLen - 1).trimEnd()}…`
}

export function mailDocumentTitle(subject: string | null | undefined): string {
  const trimmed = subject?.replace(/\s+/g, " ").trim()
  if (trimmed) {
    return formatSuiteDocumentTitle(truncateSubjectForTitle(trimmed), "mail")
  }
  return MAIL_INBOX_DOCUMENT_TITLE
}

export function suiteRootMetadata(): Metadata {
  return {
    title: { default: APP_LABELS.suite },
    description: DESCRIPTIONS.suite,
    icons: ICONS.mail,
  }
}

export function suitePageMetadata({
  app,
  title,
  titleSegment,
  description,
  absoluteTitle = false,
}: PageMetadataOptions): Metadata {
  const label = APP_LABELS[app]

  let resolvedTitle: Metadata["title"]
  if (titleSegment !== undefined) {
    // Short segment — nearest ancestor `title.template` adds the product suffix once.
    resolvedTitle = titleSegment
  } else if (title === undefined) {
    resolvedTitle = {
      default: label,
      template: `%s${SUITE_TITLE_SEP}${label}`,
    }
  } else if (absoluteTitle) {
    resolvedTitle = { absolute: title }
  } else {
    // Full title already includes suffix — absolute so root/ancestor templates do not re-apply.
    resolvedTitle = { absolute: formatSuiteDocumentTitle(title, app) }
  }

  const icons = app === "suite" ? ICONS.mail : ICONS[app]

  const meta: Metadata = {
    title: resolvedTitle,
    description: description ?? DESCRIPTIONS[app],
    icons,
  }

  if (app === "drive") {
    meta.manifest = "/drive/manifest.webmanifest"
    meta.appleWebApp = {
      capable: true,
      title: "UltiDrive",
      statusBarStyle: "default",
    }
  }

  return meta
}

export function driveDocumentTitle(segments?: string[]): string {
  const route = parseDriveSegments(segments)
  switch (route.view) {
    case "recent":
      return "Récents"
    case "starred":
      return "Favoris"
    case "trash":
      return "Corbeille"
    case "shared":
      return route.pathSegments.length > 0
        ? displayFileName(route.pathSegments.at(-1)!)
        : "Partagés avec moi"
    case "search":
      return "Recherche"
    default:
      if (route.pathSegments.length > 0) {
        return displayFileName(route.pathSegments.at(-1)!)
      }
      return "Mon Drive"
  }
}