import * as db from '../../db/companysetting.js';

// #region Helpers

const ALLOWED_KEYS = [
    'ui.theme',
    'keys.tavily',
    'keys.openrouter',
    'keys.serper',
    'systemprompt-prefix',
    'systemprompt-suffix',
    'default-model',
    'modelslug',
    'modelslugflag',
    'modelreasoning',
    'modelslugimage',
];

export const DEFAULT_SETTINGS = {
    'modelslug': 'openai/gpt-6-luna',
    'modelslugflag': 'floor',
    'modelreasoning': 'medium',
    'modelslugimage': 'meta/muse-image',
};

const WRITEONLY_KEYS = new Set([
    'keys.tavily',
    'keys.openrouter',
    'keys.serper',
]);

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

function settingErrorStatus(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 === 'Invalid setting') return 400;
    return 500;
}

/**
 * Shapes a setting for the API response, stripping the internal `frontend` flag.
 * @param {{key: string, value: string|null, frontend?: boolean}|undefined} s
 * @returns {{key: string, value: string|null}}
 */
function shapeSetting(s) {
    return { key: s.key, value: s.value ?? null };
}

// #endregion

/**
 * Registers company-settings routes for the authenticated user's selected company.
 * @param {import('express').Application} app
 * @param {string} [basePath='']
 */
export function register(app, basePath = '') {
    /**
     * @openapi
     * /company/setting:
     *   get:
     *     tags: [CompanySetting]
     *     summary: List company settings
     *     description: |
     *       Returns the visible settings of the authenticated user's selected
     *       company: the full set of allowed keys (with `value: null` when unset)
     *       plus any stored settings that are frontend-visible. The `frontend`
     *       flag is stripped from responses.
     *     security:
     *       - cookieAuth: []
     *     x-markdown: companysetting/list.md
     *     responses:
     *       200:
     *         description: Company settings
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 settings:
     *                   type: array
     *                   items:
     *                     $ref: '#/components/schemas/CompanySetting'
     *       400:
     *         description: 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'
     */
    // #region GET /company/setting

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

        try {
            const stored = await db.list(req.user.id, {});
            const byKey = new Map(stored.map((s) => [s.key, s]));

            // Visible = named/allowed keys plus any stored setting with frontend=true.
            const visibleKeys = new Set(ALLOWED_KEYS);
            for (const s of stored) {
                if (s.frontend) visibleKeys.add(s.key);
            }

            const settings = [...visibleKeys].map((key) => {
                if (byKey.has(key)) {
                    return shapeSetting(byKey.get(key));
                }
                return shapeSetting({ key, value: DEFAULT_SETTINGS[key] ?? null });
            });

            res.status(200).json({ settings });
        } catch (error) {
            const status = settingErrorStatus(error);
            if (status === 500) console.error('List company settings failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /company/setting/{key}:
     *   get:
     *     tags: [CompanySetting]
     *     summary: Get company setting by key
     *     description: |
     *       Returns a single company setting for the authenticated user's selected
     *       company, or `404` if it does not exist.
     *     security:
     *       - cookieAuth: []
     *     x-markdown: companysetting/get.md
     *     parameters:
     *       - in: path
     *         name: key
     *         required: true
     *         schema:
     *           type: string
     *     responses:
     *       200:
     *         description: Company setting
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 setting:
     *                   $ref: '#/components/schemas/CompanySetting'
     *       400:
     *         description: 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 setting or company not found
     *         content:
     *           application/json:
     *             schema:
     *               $ref: '#/components/schemas/Error'
     */
    // #region GET /company/setting/:key

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

        const key = String(req.params.key ?? '');
        if (!key.trim()) {
            return res.status(400).json({ error: 'key is required' });
        }

        try {
            const setting = await db.getByKey(req.user.id, key);
            // Stored setting that is frontend-visible
            if (setting && setting.frontend) {
                return res.status(200).json({ setting: shapeSetting(setting) });
            }
            // If unset, but it's an allowed key with a default or allowed frontend key
            if (!setting && ALLOWED_KEYS.includes(key) && !WRITEONLY_KEYS.has(key)) {
                return res.status(200).json({
                    setting: shapeSetting({ key, value: DEFAULT_SETTINGS[key] ?? null }),
                });
            }
            // Only frontend-visible settings are exposed; others are treated as absent.
            return res.status(404).json({ error: 'Company setting not found' });
        } catch (error) {
            const status = settingErrorStatus(error);
            if (status === 500) console.error('Get company setting failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion

    /**
     * @openapi
     * /company/setting/{key}:
     *   put:
     *     tags: [CompanySetting]
     *     summary: Upsert company setting
     *     description: |
     *       Sets (upserts) a company setting for the selected company.
     *       Only a fixed allow-list of keys can be set: `ui.theme`, `keys.tavily`,
     *       `keys.openrouter`, `keys.serper`, `systemprompt-prefix`,
     *       `systemprompt-suffix`, `default-model`, `modelslug`,
     *       `modelslugflag`, `modelreasoning`, `modelslugimage`.
     *     security:
     *       - cookieAuth: []
     *     x-markdown: companysetting/set.md
     *     parameters:
     *       - in: path
     *         name: key
     *         required: true
     *         schema:
     *           type: string
     *     requestBody:
     *       required: true
     *       content:
     *         application/json:
     *           schema:
     *             type: object
     *             required: [value]
     *             properties:
     *               value:
     *                 type: string
     *               frontend:
     *                 type: boolean
     *             example:
     *               value: dark
     *               frontend: true
     *     responses:
     *       200:
     *         description: Upserted company setting
     *         content:
     *           application/json:
     *             schema:
     *               type: object
     *               properties:
     *                 setting:
     *                   $ref: '#/components/schemas/CompanySetting'
     *       400:
     *         description: Invalid setting, invalid key, 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'
     */
    // #region PUT /company/setting/:key

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

        const key = String(req.params.key ?? '');
        if (!key.trim()) {
            return res.status(400).json({ error: 'key is required' });
        }

        if (!ALLOWED_KEYS.includes(key)) {
            return res.status(400).json({ error: 'Invalid setting' });
        }

        const value = req.body?.value;
        const frontend = req.body?.frontend;

        if (typeof value !== 'string') {
            return res.status(400).json({ error: 'Invalid setting' });
        }

        const trimmedVal = value.trim();
        if (key === 'modelslugflag' && !['', 'floor', 'nitro'].includes(trimmedVal)) {
            return res.status(400).json({ error: 'Invalid setting' });
        }
        if (key === 'modelreasoning' && !['none', 'low', 'medium', 'high'].includes(trimmedVal)) {
            return res.status(400).json({ error: 'Invalid setting' });
        }

        let valToSave = value;
        if (key === 'modelslug' && !trimmedVal) {
            valToSave = DEFAULT_SETTINGS.modelslug;
        }

        const input = { key, value: valToSave };
        if (typeof frontend === 'boolean') {
            input.frontend = frontend;
        } else if (!WRITEONLY_KEYS.has(key)) {
            input.frontend = true;
        }

        try {
            const setting = await db.set(req.user.id, input);
            res.status(200).json({ setting: shapeSetting(setting) });
        } catch (error) {
            const status = settingErrorStatus(error);
            if (status === 500) console.error('Set company setting failed:', error);
            res.status(status).json({ error: error.message });
        }
    });

    // #endregion
}