import * as db from '../../db/shipment.js';
import { createAndAttachManifestPdf } from '../../services/manifestPdf.js';
import { emit } from '../sse.js';

// #region Helpers

function requireSelectedCompany(req) {
    const companyId = req.user?.selectedCompanyId;
    if (companyId == null) {
        return { error: 'No company selected' };
    }
    return { companyId };
}

function parsePositiveInt(value, field) {
    const id = Number(value);
    if (!Number.isInteger(id) || id <= 0) {
        return { error: `${field} is required` };
    }
    return { id };
}

function shipmentErrorStatus(error) {
    if (error.message === 'No company selected') return 400;
    if (error.message === 'Not authorized') return 403;
    if (error.message?.endsWith(' not found')) return 404;
    if (
        error.message?.endsWith(' required') ||
        error.message?.startsWith('Article (') ||
        error.message?.includes('Invalid lines') ||
        error.message === 'Invalid state' ||
        error.message === 'Invalid offset' ||
        error.message === 'Invalid limit' ||
        error.message === 'Invalid seekMonths'
    ) {
        return 400;
    }
    if (
        error.message?.startsWith('Shipment amount exceeds') ||
        error.message?.includes('cannot be deleted') ||
        error.message?.includes('cannot be undone') ||
        error.message?.includes('already shipped')
    ) {
        return 409;
    }
    return 500;
}

function emitShipmentEvents(companyId) {
    emit('order', { companyId });
    emit('shipment', { companyId });
}

// #endregion

/**
 * Registers shipment routes (shipments belong to an order).
 * @param {import('express').Application} app
 * @param {string} [basePath='']
 */
export function register(app, basePath = '') {
    /**
     * @openapi
     * /order/{id}/shipment:
     *   get:
     *     tags: [Shipment]
     *     summary: List shipments of an order
     *     description: Lists all shipment manifests belonging to the specified order.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Order ID
     *     responses:
     *       200:
     *         description: List of shipments
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 shipments:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/Shipment'
     *       400:
     *         description: Invalid ID or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Order not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /order/:id/shipment

    app.get(`${basePath}/order/:id/shipment`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        try {
            const shipments = await db.listByOrderId(req.user.id, parsedId.id);
            res.status(200).json({ shipments });
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('List shipments failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /order/{id}/shipment:
     *   post:
     *     tags: [Shipment]
     *     summary: Create shipment for an order
     *     description: |
     *       Creates a new shipment manifest (Lieferschein) for an order containing one, some, or all items from the order.
     *       If `lines` is omitted or empty, all remaining unshipped items from the order are included automatically.
     *       On individual line items, `amount` is optional and defaults to the remaining unshipped quantity for that article.
     *       Auto-assigns the shipment number formatted as `<order_number><shipment_prefix><index>`, e.g. `AUF-000001-L-1`.
     *       Updates the materialized `ordersummary` table (`shipped_quantity`, `is_shipped`) and emits SSE events
     *       (`order`, `shipment`) so that the order list and summary tables are rerendered in real time.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Order ID
     *     requestBody:
     *       required: false
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             properties:
     *               date:
     *                 type: string
     *                 format: date
     *                 description: Optional shipment date (defaults to current date)
     *               externalNumber:
     *                 type: string
     *                 description: Optional external delivery note reference (defaults to order.externalNumber or order.number)
     *               lines:
     *                 type: array
     *                 description: Optional positions to ship. If omitted, all remaining unshipped items are shipped.
     *                 items:
     *                   type: object
     *                   required: [sku]
     *                   properties:
     *                     sku:
     *                       type: string
     *                       description: Article SKU
     *                     amount:
     *                       type: number
     *                       description: Quantity to ship. Defaults to remaining unshipped quantity for this SKU.
     *                     name:
     *                       type: string
     *                     pu:
     *                       type: number
     *                     net:
     *                       type: number
     *                     rebate:
     *                       type: number
     *                     taxrate:
     *                       type: number
     *                     comment:
     *                       type: string
     *     responses:
     *       201:
     *         description: Created shipment
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 shipment:
     *                   $ref: '#/components/schemas/Shipment'
     *       400:
     *         description: Validation error or article not in order
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Order not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       409:
     *         description: Cumulative shipment amount exceeds ordered amount, or all items are already shipped
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region POST /order/:id/shipment

    app.post(`${basePath}/order/:id/shipment`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        try {
            const shipment = await db.create(req.user.id, {
                ...(req.body ?? {}),
                orderId: parsedId.id,
            });
            emitShipmentEvents(selected.companyId);
            res.status(201).json({ shipment });
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Create shipment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment:
     *   get:
     *     tags: [Shipment]
     *     summary: List shipments
     *     description: |
     *       Company-wide paginated list of shipment manifests (`manifest` rows with `type = 'shipment'`)
     *       with delivery state, package tracking info, and order references.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: query
     *         name: offset
     *         schema:
     *           type: integer
     *           default: 0
     *           minimum: 0
     *         description: Number of shipments to skip
     *       - in: query
     *         name: limit
     *         schema:
     *           type: integer
     *           default: 50
     *           minimum: 1
     *           maximum: 1000
     *         description: Number of shipments to return
     *       - in: query
     *         name: search
     *         schema:
     *           type: string
     *         description: Free-text search matching shipment number, order number, external number, tracking code, or customer name
     *       - in: query
     *         name: state
     *         schema:
     *           type: string
     *           enum: [new, delivered, returned]
     *         description: Optional filter by delivery state
     *       - in: query
     *         name: seekMonths
     *         schema:
     *           type: integer
     *         description: Negative integer for cutoff months ago (e.g. -1 for shipments older than 1 month)
     *     responses:
     *       200:
     *         description: Paginated shipment list
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               required: [shipments, total, unfilteredTotal, offset, limit]
     *               properties:
     *                 shipments:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/ShipmentSummary'
     *                 total:
     *                   type: integer
     *                 unfilteredTotal:
     *                   type: integer
     *                 offset:
     *                   type: integer
     *                 limit:
     *                   type: integer
     *       400:
     *         description: Invalid query parameters or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       403:
     *         description: Not authorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /shipment

    app.get(`${basePath}/shipment`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const rawOffset = req.query.offset;
        const rawLimit = req.query.limit;

        let offset = 0;
        let limit = 50;

        if (rawOffset !== undefined) {
            offset = parseInt(rawOffset, 10);
            if (!Number.isInteger(offset) || offset < 0) {
                return res.status(400).json({ error: 'offset must be an integer >= 0' });
            }
        }

        if (rawLimit !== undefined) {
            limit = parseInt(rawLimit, 10);
            if (!Number.isInteger(limit) || limit < 1 || limit > 1000) {
                return res.status(400).json({ error: 'limit must be an integer between 1 and 1000' });
            }
        }

        const search = typeof req.query.search === 'string' && req.query.search.trim() !== ''
            ? req.query.search.trim()
            : undefined;

        let state = undefined;
        if (typeof req.query.state === 'string' && req.query.state.trim() !== '') {
            const trimmedState = req.query.state.trim().toLowerCase();
            if (!['new', 'delivered', 'returned'].includes(trimmedState)) {
                return res.status(400).json({ error: 'Invalid state' });
            }
            state = trimmedState;
        }

        let seekMonths = undefined;
        if (req.query.seekMonths !== undefined && req.query.seekMonths !== '') {
            const parsedSeek = parseInt(req.query.seekMonths, 10);
            if (!Number.isInteger(parsedSeek)) {
                return res.status(400).json({ error: 'seekMonths must be an integer' });
            }
            seekMonths = parsedSeek;
        }

        try {
            const result = await db.list(req.user.id, {
                offset,
                limit,
                search,
                state,
                seekMonths,
            });
            res.status(200).json(result);
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('List shipments failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}:
     *   get:
     *     tags: [Shipment]
     *     summary: Get shipment by ID
     *     description: Retrieves shipment header, article positions, and attached packages.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *     responses:
     *       200:
     *         description: Shipment details
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 shipment:
     *                   $ref: '#/components/schemas/Shipment'
     *       400:
     *         description: Invalid ID or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /shipment/:id

    app.get(`${basePath}/shipment/:id`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        try {
            const shipment = await db.getById(req.user.id, parsedId.id);
            res.status(200).json({ shipment });
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Get shipment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}:
     *   patch:
     *     tags: [Shipment]
     *     summary: Update shipment state or metadata
     *     description: |
     *       Updates delivery state (`new`, `delivered`, `returned`) for the shipment.
     *       Emits SSE events (`shipment`, `order`) so connected clients rerender in real time.
     *     security:
     *       - cookieAuth: []
     *     x-signals: [shipment, order]
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *     requestBody:
     *       required: true
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             properties:
     *               state:
     *                 type: string
     *                 enum: [new, delivered, returned]
     *                 description: Delivery state
     *             example:
     *               state: delivered
     *     responses:
     *       200:
     *         description: Updated shipment
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 shipment:
     *                   $ref: '#/components/schemas/Shipment'
     *       400:
     *         description: Invalid state, invalid ID, or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region PATCH /shipment/:id

    app.patch(`${basePath}/shipment/:id`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        const { state } = req.body ?? {};
        if (state !== undefined) {
            if (typeof state !== 'string' || !['new', 'delivered', 'returned'].includes(state.trim().toLowerCase())) {
                return res.status(400).json({ error: 'Invalid state' });
            }
        }

        try {
            const shipment = await db.update(req.user.id, parsedId.id, {
                state: state ? state.trim().toLowerCase() : undefined,
            });
            emitShipmentEvents(selected.companyId);
            res.status(200).json({ shipment });
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Update shipment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}:
     *   delete:
     *     tags: [Shipment]
     *     summary: Delete shipment
     *     description: Deletes an unshipped shipment manifest. Shipped shipments cannot be deleted.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *     responses:
     *       204:
     *         description: Shipment deleted
     *       400:
     *         description: Invalid ID or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       409:
     *         description: Shipped shipment cannot be deleted
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region DELETE /shipment/:id

    app.delete(`${basePath}/shipment/:id`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        try {
            await db.remove(req.user.id, parsedId.id);
            emitShipmentEvents(selected.companyId);
            res.status(204).end();
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Delete shipment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}/pdf:
     *   post:
     *     tags: [Shipment]
     *     summary: Generate and attach shipment PDF (delivery note)
     *     description: |
     *       Generates an A4 delivery note PDF document for the shipment with line items and package tracking.
     *       Shipping slips contain no price information.
     *       Attaches the PDF as a `manifestattachment` to the shipment so it can be printed or attached to packages.
     *     security:
     *       - cookieAuth: []
     *     x-signals: [shipment]
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *     responses:
     *       201:
     *         description: PDF generated and attached to shipment
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               required: [attachment, fileUrl]
     *               properties:
     *                 attachment:
     *                   $ref: '#/components/schemas/DeliveryFile'
     *                 fileUrl:
     *                   type: string
     *                   example: /shipment/1/file/5
     *       400:
     *         description: Invalid ID or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       403:
     *         description: Not authorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region POST /shipment/:id/pdf

    app.post(`${basePath}/shipment/:id/pdf`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        try {
            const { attachment } = await createAndAttachManifestPdf(
                req.user.id,
                selected.companyId,
                parsedId.id,
                'shipment'
            );

            res.status(201).json({
                attachment,
                fileUrl: `/shipment/${parsedId.id}/file/${attachment.fileId}`,
            });
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Create shipment PDF failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}/file/{fileId}:
     *   get:
     *     tags: [Shipment]
     *     summary: Get shipment attachment file content
     *     description: |
     *       Returns the full binary content of an attached file (e.g. shipment delivery note PDF)
     *       for the specified shipment. Supports HTTP caching via ETag (SHA-256 hash) and 304 Not Modified.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *       - in: path
     *         name: fileId
     *         required: true
     *         schema:
     *           type: integer
     *         description: File ID or attachment ID
     *       - in: query
     *         name: download
     *         required: false
     *         schema:
     *           type: boolean
     *         description: When true, sets Content-Disposition to attachment instead of inline
     *     responses:
     *       200:
     *         description: Binary file content
     *         content:
     *           application/pdf:
     *             schema:
     *               type: string
     *               format: binary
     *           application/octet-stream:
     *             schema:
     *               type: string
     *               format: binary
     *       304:
     *         description: Not modified
     *       400:
     *         description: Invalid ID or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment or file not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /shipment/:id/file/:fileId

    app.get(`${basePath}/shipment/:id/file/:fileId`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const parsedId = parsePositiveInt(req.params.id, 'id');
        if (parsedId.error) {
            return res.status(400).json({ error: parsedId.error });
        }

        const parsedFileId = parsePositiveInt(req.params.fileId, 'fileId');
        if (parsedFileId.error) {
            return res.status(400).json({ error: parsedFileId.error });
        }

        try {
            const attachment = await db.getFile(req.user.id, parsedId.id, parsedFileId.id);

            if (attachment.hash) {
                const etag = `"${attachment.hash}"`;
                res.setHeader('ETag', etag);
                const ifNoneMatch = req.headers['if-none-match'];
                if (ifNoneMatch === etag || ifNoneMatch === attachment.hash) {
                    return res.status(304).end();
                }
            }

            const isDownload = req.query.download === '1' || req.query.download === 'true';
            const dispositionType = isDownload ? 'attachment' : 'inline';
            const filename = attachment.name || `file-${attachment.fileId}`;
            const asciiName = filename.replace(/["\r\n\\]/g, '_');
            const encodedName = encodeURIComponent(filename).replace(/['()]/g, escape);

            res.setHeader('Content-Type', attachment.mimetype || 'application/octet-stream');
            res.setHeader('Content-Disposition', `${dispositionType}; filename="${asciiName}"; filename*=UTF-8''${encodedName}`);
            res.setHeader('Cache-Control', 'private, max-age=86400');

            if (attachment.content && Buffer.isBuffer(attachment.content)) {
                res.setHeader('Content-Length', String(attachment.content.length));
                return res.status(200).send(attachment.content);
            } else {
                const buffer = Buffer.from(attachment.content || '');
                res.setHeader('Content-Length', String(buffer.length));
                return res.status(200).send(buffer);
            }
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Get shipment file failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /shipment/{id}/file/{fileId}:
     *   delete:
     *     tags: [Shipment]
     *     summary: Delete shipment file attachment
     *     description: |
     *       Removes a file attachment from the shipment and deletes the underlying file.
     *     security:
     *       - cookieAuth: []
     *     x-signals: [shipment, order]
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Shipment ID
     *       - in: path
     *         name: fileId
     *         required: true
     *         schema:
     *           type: integer
     *         description: File ID or attachment ID
     *     responses:
     *       204:
     *         description: Attachment deleted
     *       400:
     *         description: Invalid parameters or no company selected
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       401:
     *         description: Unauthorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       403:
     *         description: Not authorized
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *       404:
     *         description: Shipment or attachment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region DELETE /shipment/:id/file/:fileId

    app.delete(`${basePath}/shipment/:id/file/:fileId`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

        const id = Number(req.params.id);
        if (!Number.isInteger(id) || id <= 0) {
            return res.status(400).json({ error: 'id is required' });
        }

        const fileId = Number(req.params.fileId);
        if (!Number.isInteger(fileId) || fileId <= 0) {
            return res.status(400).json({ error: 'fileId is required' });
        }

        try {
            await db.removeAttachment(req.user.id, id, fileId);
            emitShipmentEvents(selected.companyId);
            res.sendStatus(204);
        } catch (error) {
            const status = shipmentErrorStatus(error);
            if (status === 500) console.error('Delete shipment attachment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion
}