"use strict";

const express = require("express");
const fs = require("fs");
const { sniffImageType } = require("../../core/images/sniff");
const { isHeic } = require("../../core/images/heic");
const { BadRequestError, NotFoundError } = require("../../errors");

const JOB_ID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;

/**
 * @param {Object} deps
 * @param {import('../../core/history/history-service').HistoryService} deps.historyService
 * @param {import('multer').Multer} deps.upload
 * @param {import('../../logger').Logger} deps.logger
 */
function createHistoryRoutes({ historyService, upload, logger }) {
  const router = express.Router();

  router.get("/history", (req, res, next) => {
    try {
      res.json({ ok: true, versions: historyService.getHistory() });
    } catch (err) {
      next(err);
    }
  });

  router.post("/history/import", upload.single("photo"), async (req, res, next) => {
    try {
      if (!req.file || !req.file.buffer) {
        throw new BadRequestError("Выберите фотографию для импорта.");
      }

      const isHeicFile = isHeic(req.file) || sniffImageType(req.file.buffer) === "heic";
      const sniffedType = sniffImageType(req.file.buffer);

      if (!isHeicFile && !sniffedType) {
        throw new BadRequestError(
          "Файл не является поддерживаемым изображением (JPEG, PNG, WebP или HEIC)."
        );
      }

      const version = await historyService.importPhoto({
        buffer: req.file.buffer,
        mimetype: req.file.mimetype,
        originalname: req.file.originalname,
      });

      logger.info("Импорт фотографии", {
        versionId: version.id,
        ext: version.ext,
        width: version.width,
        height: version.height,
      });

      res.json({ ok: true, version });
    } catch (err) {
      next(err);
    }
  });

  router.delete("/history/:id", async (req, res, next) => {
    try {
      const { id } = req.params;
      if (!JOB_ID_PATTERN.test(id)) {
        throw new BadRequestError("Некорректный идентификатор версии.");
      }

      const existing = historyService.getVersion(id);
      if (!existing) {
        throw new NotFoundError("Версия не найдена в истории.");
      }

      const result = await historyService.removeCascade(id);
      logger.audit("Удаление версии истории", {
        versionId: id,
        removedCount: result.removed.length,
      });

      res.json({ ok: true, versions: result.remaining });
    } catch (err) {
      next(err);
    }
  });

  // Alias /image.jpg for backward compatibility -> 302 redirect to actual ext
  router.get("/history/:id/image.jpg", (req, res, next) => {
    try {
      const { id } = req.params;
      if (!JOB_ID_PATTERN.test(id)) {
        throw new BadRequestError("Некорректный идентификатор версии.");
      }

      const version = historyService.getVersion(id);
      if (!version) {
        throw new NotFoundError("Версия не найдена в истории.");
      }

      const targetExt = version.ext || "jpg";
      if (targetExt !== "jpg") {
        return res.redirect(302, `/api/history/${id}/image.${targetExt}`);
      }

      // If ext is jpg, serve it directly
      const fileInfo = historyService.getVersionFile(id);
      fileInfo
        .then(({ filePath, contentType }) => {
          res.setHeader("content-type", contentType);
          res.setHeader("cache-control", "no-store");
          res.setHeader(
            "content-disposition",
            `inline; filename*=UTF-8''${encodeURIComponent(`version-${id.slice(0, 8)}.jpg`)}`
          );
          fs.createReadStream(filePath).pipe(res);
        })
        .catch(next);
    } catch (err) {
      next(err);
    }
  });

  // Direct route for /history/:id/image.:ext (e.g. image.png, image.webp, image.jpg)
  router.get("/history/:id/image.:ext", async (req, res, next) => {
    try {
      const { id } = req.params;
      if (!JOB_ID_PATTERN.test(id)) {
        throw new BadRequestError("Некорректный идентификатор версии.");
      }

      const { version, filePath, contentType } = await historyService.getVersionFile(id);

      res.setHeader("content-type", contentType);
      res.setHeader("cache-control", "no-store");
      res.setHeader(
        "content-disposition",
        `inline; filename*=UTF-8''${encodeURIComponent(`version-${id.slice(0, 8)}.${version.ext || "jpg"}`)}`
      );

      fs.createReadStream(filePath).pipe(res);
    } catch (err) {
      next(err);
    }
  });

  return router;
}

module.exports = {
  createHistoryRoutes,
  JOB_ID_PATTERN,
};