import * as db from '../../db/order.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 orderErrorStatus(error) {
    if (error.message === 'No company selected') return 400;
    if (error.message === 'Not authorized') return 403;
    if (error.message === 'Company not found') return 404;
    if (error.message === 'Order not found') return 404;
    if (error.message === 'Manifest not found') return 404;
    if (error.message === 'Attachment not found') return 404;
    if (error.message === 'Entity not found') return 404;
    if (error.message === 'Article not found') return 404;
    if (error.message === 'No entity selected') return 400;
    if (error.message === 'Order number already exists') return 409;
    if (error.message === 'Invalid entityId') return 400;
    if (error.message === 'Invalid order') return 400;
    if (error.message === 'Invalid lines') return 400;
    if (error.message === 'Invalid offset') return 400;
    if (error.message === 'Invalid limit') return 400;
    if (error.message === 'Invalid seekMonths') return 400;
    if (error.message === 'File name required') return 400;
    if (error.message === 'Mimetype required') return 400;
    if (error.message === 'Content required') return 400;
    if (error.message?.includes('parent article') || error.message?.includes('A parent article')) return 400;
    return 500;
}

// #endregion

/**
 * Registers sales-order routes for the authenticated user's selected company.
 * @param {import('express').Application} app
 * @param {string} [basePath='']
 */
export function register(app, basePath = '') {
    /**
     * @openapi
     * /order:
     *   get:
     *     tags: [Order]
     *     summary: List orders
     *     description: |
     *       Lists sales orders (`manifest` rows with `type = 'order'`)
     *       for the authenticated user's selected company.
     *       Results are paged, include line items, shipping, payment, and provide total unpaged count as well as unfiltered count.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: query
     *         name: offset
     *         schema:
     *           type: integer
     *           default: 0
     *           minimum: 0
     *         description: Number of orders to skip
     *       - in: query
     *         name: limit
     *         schema:
     *           type: integer
     *           default: 50
     *           minimum: 1
     *           maximum: 1000
     *         description: Number of orders to return
     *       - in: query
     *         name: search
     *         schema:
     *           type: string
     *         description: Free-text search matching order number, external number, or customer name
     *       - in: query
     *         name: onlyUnpaid
     *         schema:
     *           type: boolean
     *           default: false
     *         description: When true, returns only unpaid orders (including overpaid orders)
     *       - in: query
     *         name: onlyUndelivered
     *         schema:
     *           type: boolean
     *           default: false
     *         description: When true, returns only undelivered orders
     *       - in: query
     *         name: seekMonths
     *         schema:
     *           type: integer
     *         description: Negative integer for cutoff months ago (e.g. -1 for orders older than 1 month)
     *     x-markdown: order/list.md
     *     responses:
     *       200:
     *         description: Order list
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               required: [orders, total, unfilteredTotal, offset, limit]
     *               properties:
     *                 orders:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/Order'
     *                 total:
     *                   type: integer
     *                   description: Total number of filtered orders
     *                 unfilteredTotal:
     *                   type: integer
     *                   description: Total number of orders without any filters applied
     *                 offset:
     *                   type: integer
     *                   description: Number of orders skipped
     *                 limit:
     *                   type: integer
     *                   description: Number of orders returned
     *       400:
     *         description: Invalid query parameters, invalid offset, invalid limit, 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: Company not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *   post:
     *     tags: [Order]
     *     summary: Create order
     *     description: |
     *       Creates a sales order with header and lines in one transaction.
     *       `date` is the document date (expected delivery).
     *       `entityId` must be a company customer (not Lieferanten).
     *       Each line requires `sku` or `name`, `amount`, `net`, and `taxrate` (rate); `pu` defaults to `1`; `rebate` defaults to `0`; `shippable` defaults to `true` (`false` = not shippable, excluded from order completeness).
     *     security:
     *       - cookieAuth: []
     *     x-markdown: order/create.md
     *     requestBody:
     *       required: true
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             required: [number, date, entityId, lines]
     *             properties:
     *               number:
     *                 type: string
     *               date:
     *                 type: string
     *                 format: date-time
     *                 description: Document date / expected delivery
     *               entityId:
     *                 type: integer
     *                 description: Customer entity (manifest.entity_id)
     *               externalNumber:
     *                 type: string
     *                 nullable: true
     *                 description: External customer reference number (manifest.external_number)
     *               lines:
     *                 type: array
     *                 items:
     *                   $ref: '#/components/schemas/ManifestLineInput'
     *             example:
     *               number: O-2026-001
     *               date: '2026-09-15'
     *               entityId: 1
     *               lines:
     *                 - sku: '1'
     *                   name: 'Sample Article'
     *                   pu: 1
     *                   amount: 10
     *                   net: 99.5
     *                   taxrate: 19
     *     responses:
     *       201:
     *         description: Created order
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 order:
     *                   $ref: '#/components/schemas/Order'
     *       400:
     *         description: Invalid order, invalid lines, 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: Company, entity, or article not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /order

    app.get(`${basePath}/order`, 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;

        const onlyUnpaid = req.query.onlyUnpaid === 'true';
        const onlyUndelivered = req.query.onlyUndelivered === 'true';

        let entityId = undefined;
        if (req.query.entityId !== undefined && req.query.entityId !== '') {
            const parsedEntity = parseInt(req.query.entityId, 10);
            if (!Number.isInteger(parsedEntity) || parsedEntity <= 0) {
                return res.status(400).json({ error: 'entityId must be a positive integer' });
            }
            entityId = parsedEntity;
        }

        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,
                onlyUnpaid: onlyUnpaid ? true : undefined,
                onlyUndelivered: onlyUndelivered ? true : undefined,
                entityId,
                seekMonths,
            });
            res.status(200).json(result);
        } catch (error) {
            const status = orderErrorStatus(error);
            if (status === 500) console.error('List orders failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    // #region POST /order

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

        const { number, date, createdAt, entityId, externalNumber, lines } = req.body ?? {};
        if (entityId === undefined || entityId === null) {
            return res.status(400).json({ error: 'No entity selected' });
        }
        if (typeof entityId !== 'number' || !Number.isInteger(entityId) || entityId <= 0) {
            return res.status(400).json({ error: 'Invalid entityId' });
        }

        try {
            const order = await db.create(req.user.id, {
                number,
                date,
                createdAt,
                entityId,
                externalNumber: externalNumber !== undefined && externalNumber !== null ? String(externalNumber) : externalNumber,
                lines,
            });
            res.status(201).json({ order });
        } catch (error) {
            const status = orderErrorStatus(error);
            if (status === 500) console.error('Create order failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /order/{id}:
     *   get:
     *     tags: [Order]
     *     summary: Get order
     *     description: Returns a sales order with lines for the selected company.
     *     security:
     *       - cookieAuth: []
     *     x-markdown: order/get.md
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *     responses:
     *       200:
     *         description: Order
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 order:
     *                   $ref: '#/components/schemas/Order'
     *       400:
     *         description: No company selected or invalid id
     *         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: Order or company not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *   patch:
     *     tags: [Order]
     *     summary: Update order
     *     description: |
     *       Patches header fields that are present. If `lines` is present, replaces
     *       all lines; if omitted, leaves lines unchanged. Returns the full order.
     *       `date` is the document date (expected delivery).
     *     security:
     *       - cookieAuth: []
     *     x-markdown: order/update.md
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *     requestBody:
     *       required: true
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             properties:
     *               number:
     *                 type: string
     *               date:
     *                 type: string
     *                 format: date-time
     *                 description: Document date / expected delivery
     *               entityId:
     *                 type: integer
     *                 nullable: true
     *               externalNumber:
     *                 type: string
     *                 nullable: true
     *                 description: External customer reference number (manifest.external_number)
     *               lines:
     *                 type: array
     *                 items:
     *                   $ref: '#/components/schemas/ManifestLineInput'
     *             example:
     *               number: O-2026-001b
     *               lines: []
     *     responses:
     *       200:
     *         description: Updated order
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 order:
     *                   $ref: '#/components/schemas/Order'
     *       400:
     *         description: Invalid order, invalid lines, 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: Order, entity, article, or company not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     *   delete:
     *     tags: [Order]
     *     summary: Delete order
     *     description: Deletes the sales order (`manifestarticle` rows cascade).
     *     security:
     *       - cookieAuth: []
     *     x-markdown: order/delete.md
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *     responses:
     *       204:
     *         description: Deleted
     *       400:
     *         description: No company selected or invalid id
     *         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: Order not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /order/:id

    app.get(`${basePath}/order/:id`, 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' });
        }

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

    // #endregion

    // #region PATCH /order/:id

    app.patch(`${basePath}/order/:id`, 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 body = req.body ?? {};
        const patch = {};
        if (Object.prototype.hasOwnProperty.call(body, 'number')) {
            patch.number = body.number;
        }
        if (Object.prototype.hasOwnProperty.call(body, 'date')) {
            patch.date = body.date;
        }
        if (Object.prototype.hasOwnProperty.call(body, 'createdAt')) {
            patch.createdAt = body.createdAt;
        }
        if (Object.prototype.hasOwnProperty.call(body, 'entityId')) {
            if (body.entityId === null) {
                return res.status(400).json({ error: 'No entity selected' });
            }
            if (typeof body.entityId !== 'number' || !Number.isInteger(body.entityId) || body.entityId <= 0) {
                return res.status(400).json({ error: 'Invalid entityId' });
            }
            patch.entityId = body.entityId;
        }
        if (Object.prototype.hasOwnProperty.call(body, 'externalNumber')) {
            patch.externalNumber = body.externalNumber !== null && body.externalNumber !== undefined
                ? String(body.externalNumber)
                : null;
        }
        if (Object.prototype.hasOwnProperty.call(body, 'lines')) {
            patch.lines = body.lines;
        }

        try {
            const order = await db.update(req.user.id, id, patch);
            res.status(200).json({ order });
        } catch (error) {
            const status = orderErrorStatus(error);
            if (status === 500) console.error('Update order failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    // #region DELETE /order/:id

    app.delete(`${basePath}/order/:id`, 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' });
        }

        try {
            await db.remove(req.user.id, id);
            res.sendStatus(204);
        } catch (error) {
            const status = orderErrorStatus(error);
            if (status === 500) console.error('Delete order failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /order/{id}/pdf:
     *   post:
     *     tags: [Order]
     *     summary: Generate and attach order PDF
     *     description: |
     *       Generates an A4 PDF document for the sales order with line items, prices, and tax breakdown.
     *       Attaches the PDF as a `manifestattachment` to the order so it can be printed or archived.
     *     security:
     *       - cookieAuth: []
     *     x-signals: [order]
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Order ID
     *     responses:
     *       201:
     *         description: PDF generated and attached to order
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               required: [attachment, fileUrl]
     *               properties:
     *                 attachment:
     *                   $ref: '#/components/schemas/DeliveryFile'
     *                 fileUrl:
     *                   type: string
     *                   example: /order/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: Order not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region POST /order/:id/pdf

    app.post(`${basePath}/order/:id/pdf`, 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' });
        }

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

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

    // #endregion

    /**
     * @openapi
     * /order/{id}/file/{fileId}:
     *   get:
     *     tags: [Order]
     *     summary: Get order attachment file content
     *     description: |
     *       Returns the full binary content of an attached file (e.g. order PDF)
     *       for the specified order. 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: Order 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: Order or file not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /order/:id/file/:fileId

    app.get(`${basePath}/order/: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 {
            const attachment = await db.getFile(req.user.id, id, fileId);

            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 = orderErrorStatus(error);
            if (status === 500) console.error('Get order file failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /order/{id}/file/{fileId}:
     *   delete:
     *     tags: [Order]
     *     summary: Delete order file attachment
     *     description: |
     *       Removes a file attachment from the order and deletes the underlying file.
     *     security:
     *       - cookieAuth: []
     *     x-signals: [order]
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Order 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: Order or attachment not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region DELETE /order/:id/file/:fileId

    app.delete(`${basePath}/order/: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);
            emit('order', { companyId: selected.companyId });
            res.sendStatus(204);
        } catch (error) {
            const status = orderErrorStatus(error);
            if (status === 500) console.error('Delete order attachment failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion
}