from odoo import http, exceptions
from base64 import b64decode
import hmac
from hashlib import sha256
from datetime import datetime
from time import mktime


def create_hmac(secret, a_attchment_id, e_expires):
    return hmac.new(secret.encode(), str(str(a_attchment_id) + str(e_expires)).encode(), sha256).hexdigest()


def check_hmac(secret, hash_, a_attachment_id, e_expires):
    myh = hmac.new(secret.encode(), str(str(a_attachment_id) + str(e_expires)).encode(), sha256)
    return hmac.compare_digest(str(hash_), myh.hexdigest())


class RMAController(http.Controller):

    @http.route(['/rma_label'], type='http', auth='public', website=True)
    def index(self, *args, **request):
        a_attachment_id = request.get('a')
        e_expires = request.get('e')
        hash = request.get('h')

        if not all([a_attachment_id, e_expires, hash]):
            return http.Response('Invalid Request', status=400)

        now = datetime.utcnow()
        now = int(mktime(now.timetuple()))

        config = http.request.env['ir.config_parameter'].sudo()
        secret = str(config.search([('key', '=', 'database.secret')], limit=1).value)

        if not check_hmac(secret, hash, a_attachment_id, e_expires):
            return http.Response('Invalid Request', status=400)

        if now > int(e_expires):
            return http.Response('Expired', status=404)

        attachment = http.request.env['ir.attachment'].sudo().search([('id', '=', int(a_attachment_id))], limit=1)
        if attachment:
            data = attachment.datas
            filename = attachment.name
            mimetype = attachment.mimetype
            return http.request.make_response(b64decode(data), [
                ('Content-Type', mimetype),
                ('Content-Disposition', 'attachment; filename="' + filename + '"')])
        return http.Response('Invalid Attachment', status=404)