import * as db from '../../db/categoryattributevalue.js';
import { emit } from '../sse.js';

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 emitCategorySignal(req) {
    const companyId = req.user?.selectedCompanyId;
    if (companyId == null) return;
    emit('category', { companyId });
}

function categoryAttributeValueErrorStatus(error) {
    if (error.message === 'No company selected') return 400;
    if (error.message === 'Not authorized') return 403;
    if (error.message === 'Company not found' || error.message === 'Category not found' || error.message === 'Parent not found') return 404;
    if (error.message?.startsWith('Attribute value not found')) return 404;
    if (error.message?.includes('exclusive')) return 400;
    if (error.message === 'Invalid attribute values array' || error.message === 'Invalid attributeValueId' || error.message === 'Duplicate attributeValueId') return 400;
    return 500;
}

/**
 * Registers categoryattributevalue routes under `/category/:id/attributevalue`.
 * @param {import('express').Application} app
 * @param {string} [basePath='']
 */
export function register(app, basePath = '') {
    /**
     * @openapi
     * /category/{id}/attributevalue:
     *   get:
     *     tags: [Category]
     *     summary: List category attribute values
     *     description: Fetches all attribute values assigned to a category.
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Category ID
     *     responses:
     *       200:
     *         description: List of attribute values assigned to this category
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 attributevalues:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/CategoryAttributeValue'
     *   put:
     *     tags: [Category]
     *     summary: Bulk set category attribute values
     *     description: Replaces all attribute values for a category. Enforces exclusive constraint (max one value per exclusive attribute).
     *     security:
     *       - cookieAuth: []
     *     parameters:
     *       - in: path
     *         name: id
     *         required: true
     *         schema:
     *           type: integer
     *         description: Category ID
     *     requestBody:
     *       required: true
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             required: [attributevalues]
     *             properties:
     *               attributevalues:
     *                 type: array
     *                 description: Array of attribute value IDs (numbers) or objects with id or attributeValueId
     *                 items:
     *                   oneOf:
     *                     - type: integer
     *                       description: Attribute value ID
     *                     - type: object
     *                       properties:
     *                         id:
     *                           type: integer
     *                           description: Attribute value ID
     *                         attributeValueId:
     *                           type: integer
     *                           description: Attribute value ID
     *                         sort:
     *                           type: integer
     *     responses:
     *       200:
     *         description: Updated category attribute values
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 attributevalues:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/CategoryAttributeValue'
     */
    app.get(`${basePath}/category/:id/attributevalue`, async (req, res) => {
        const selected = requireSelectedCompany(req);
        if (selected.error) {
            return res.status(400).json({ error: selected.error });
        }

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

        try {
            const attributevalues = await db.listByCategoryId(req.user.id, idParsed.id);
            res.json({ attributevalues });
        } catch (error) {
            res.status(categoryAttributeValueErrorStatus(error)).json({ error: error.message });
        }
    });

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

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

        const valuesInput = req.body?.attributevalues ?? req.body?.attributeValues ?? req.body?.attribute_values ?? req.body?.values ?? req.body;
        if (!Array.isArray(valuesInput)) {
            return res.status(400).json({ error: 'attributevalues array required' });
        }

        try {
            const attributevalues = await db.setByCategoryId(req.user.id, idParsed.id, valuesInput);
            emitCategorySignal(req);
            res.json({ attributevalues });
        } catch (error) {
            res.status(categoryAttributeValueErrorStatus(error)).json({ error: error.message });
        }
    });
}