import fs from "node:fs";
import path from "node:path";
import { fileTypeFromFile } from "file-type";
import type { Db } from "../db.js";
import type { AppConfig } from "../config.js";
import { listShades, parseFabricParams, FABRIC_STRUCTURES, type FabricRow } from "./fabric.js";

interface CatalogSource {
  id: string;
  path: string;
  thumb_path: string | null;
  mime: string;
  original_name: string;
  sha256: string;
  source_url: string | null;
  fetched_at: string | null;
  note: string | null;
}

const IMAGE_MIMES = new Set(["image/jpeg", "image/png", "image/webp"]);

export function catalogFile(base: string, relative: string | null): string | null {
  if (!relative || path.posix.isAbsolute(relative) || path.win32.isAbsolute(relative)) return null;
  const normalized = relative.replace(/\\/g, "/");
  if (normalized.split("/").some((part) => part === ".." || part.includes(":"))) return null;
  try {
    const root = fs.realpathSync(base);
    const file = fs.realpathSync(path.resolve(root, normalized));
    const rel = path.relative(root, file);
    if (!rel || rel === ".." || rel.startsWith(`..${path.sep}`) || path.isAbsolute(rel)) return null;
    return fs.statSync(file).isFile() ? file : null;
  } catch {
    return null;
  }
}

export function getCatalogFabric(db: Db, code: string): FabricRow | undefined {
  return db.prepare("SELECT * FROM fabrics WHERE code = ?").get(code) as unknown as FabricRow | undefined;
}

export function catalogCardSource(db: Db, fabric: FabricRow): CatalogSource | undefined {
  if (!fabric.card_path) return undefined;
  return db.prepare("SELECT * FROM source_assets WHERE replace(path, char(92), '/') = ? AND mime = 'application/pdf' ORDER BY id LIMIT 1")
    .get(fabric.card_path.replace(/\\/g, "/")) as unknown as CatalogSource | undefined;
}

function sourceById(db: Db, id: string): CatalogSource | undefined {
  return db.prepare("SELECT * FROM source_assets WHERE id = ?").get(id) as unknown as CatalogSource | undefined;
}

function publicSourceUrl(raw: string | null): string | null {
  if (!raw) return null;
  try {
    const url = new URL(raw);
    return ["https:", "http:"].includes(url.protocol) && !url.username && !url.password ? url.href : null;
  } catch {
    return null;
  }
}

function mediaDto(cfg: AppConfig, code: string, source: CatalogSource | undefined, pdf = false) {
  const available = source && (pdf ? source.mime === "application/pdf" : IMAGE_MIMES.has(source.mime)) && catalogFile(cfg.originalsDir, source.path);
  const url = available ? `/api/fabrics/${encodeURIComponent(code)}/media/${encodeURIComponent(source.id)}` : null;
  return {
    sourceId: source?.id ?? null,
    name: source?.original_name ?? null,
    sha256: source?.sha256 ?? null,
    sourceUrl: publicSourceUrl(source?.source_url ?? null),
    fetchedAt: source?.fetched_at ?? null,
    note: source?.note ?? null,
    status: available ? "ready" : "unavailable",
    url,
    thumbnailUrl: url && !pdf && catalogFile(cfg.derivedDir, source?.thumb_path ?? null) ? `${url}/thumb` : null,
  };
}

export function listCatalogFabrics(db: Db) {
  return db.prepare(`SELECT f.id, f.code, f.name, f.producer, f.verification,
    (SELECT COUNT(*) FROM fabric_shades s WHERE s.fabric_id = f.id) AS shadeCount
    FROM fabrics f ORDER BY f.name COLLATE NOCASE, f.code`).all();
}

export function catalogShades(db: Db, cfg: AppConfig, fabric: FabricRow) {
  return listShades(db, fabric.id).map((shade) => ({
    id: shade.id, code: shade.code, name: shade.name, colorHex: shade.color_hex, verification: shade.verification,
    official: shade.official_image_path ? mediaDto(cfg, fabric.code, sourceById(db, shade.official_image_path)) : null,
    photo: shade.photo_path ? mediaDto(cfg, fabric.code, sourceById(db, shade.photo_path)) : null,
  }));
}

export function catalogDetail(db: Db, cfg: AppConfig, fabric: FabricRow) {
  const shades = catalogShades(db, cfg, fabric);
  return {
    fabric: { id: fabric.id, code: fabric.code, name: fabric.name, producer: fabric.producer, verification: fabric.verification, aiPrompt: fabric.ai_prompt, aiStructure: fabric.ai_structure, aiNotePl: fabric.ai_note_pl, params: parseFabricParams(fabric.params_json), shadeCount: shades.length },
    shades,
    card: fabric.card_path ? mediaDto(cfg, fabric.code, catalogCardSource(db, fabric), true) : null,
    structures: FABRIC_STRUCTURES.map(({ key, label }) => ({ key, label })),
    products: db.prepare(`SELECT DISTINCT p.id, p.slug, p.name FROM products p
      JOIN variants v ON v.product_id = p.id WHERE v.fabric_id = ? ORDER BY p.name`).all(fabric.id),
  };
}

export async function catalogMedia(db: Db, cfg: AppConfig, fabric: FabricRow, sourceId: string, thumbnail = false) {
  const isCard = catalogCardSource(db, fabric)?.id === sourceId;
  const isSwatch = db.prepare("SELECT 1 FROM fabric_shades WHERE fabric_id = ? AND (official_image_path = ? OR photo_path = ?) LIMIT 1")
    .get(fabric.id, sourceId, sourceId);
  if ((!isCard && !isSwatch) || (thumbnail && !isSwatch)) return null;
  const source = sourceById(db, sourceId);
  if (!source || !(isCard ? source.mime === "application/pdf" : IMAGE_MIMES.has(source.mime))) return null;
  const original = catalogFile(cfg.originalsDir, source.path);
  if (!original) return null;
  const file = thumbnail ? catalogFile(cfg.derivedDir, source.thumb_path) : original;
  if (!file) return null;
  const mime = thumbnail ? "image/webp" : source.mime;
  try {
    if ((await fileTypeFromFile(file))?.mime !== mime) return null;
  } catch {
    return null;
  }
  return { file, mime };
}