import io
import zipfile

from odoo import _
from odoo.exceptions import AccessError, UserError
from odoo.http import Controller, content_disposition, request, route


class EmployeePayslipDownloadController(Controller):

    @route('/employee_it_declaration/my_payslips/<int:wizard_id>', type='http', auth='user')
    def download_my_payslips(self, wizard_id, **kwargs):
        wizard = request.env['employee.payslip.download.wizard'].browse(wizard_id)
        if not wizard.exists() or wizard.create_uid != request.env.user:
            return request.not_found()

        try:
            payslips = wizard._get_payslips_for_download()
        except (AccessError, UserError):
            return request.not_found()

        if wizard.download_type == 'single':
            payslip = payslips[:1]
            report, pdf_content = wizard._get_pdf_content(payslip)
            headers = [
                ('Content-Type', 'application/pdf'),
                ('Content-Length', len(pdf_content)),
                ('Content-Disposition', content_disposition(wizard._get_pdf_filename(payslip, report))),
            ]
            return request.make_response(pdf_content, headers=headers)

        zip_buffer = io.BytesIO()
        used_filenames = set()
        with zipfile.ZipFile(zip_buffer, 'w', compression=zipfile.ZIP_DEFLATED) as payslip_zip:
            for payslip in payslips:
                report, pdf_content = wizard._get_pdf_content(payslip)
                filename = self._deduplicate_filename(wizard._get_pdf_filename(payslip, report), used_filenames)
                payslip_zip.writestr(filename, pdf_content)

        zip_content = zip_buffer.getvalue()
        headers = [
            ('Content-Type', 'application/zip'),
            ('Content-Length', len(zip_content)),
            ('Content-Disposition', content_disposition(wizard._get_zip_filename())),
        ]
        return request.make_response(zip_content, headers=headers)

    @staticmethod
    def _deduplicate_filename(filename, used_filenames):
        if filename not in used_filenames:
            used_filenames.add(filename)
            return filename

        stem, extension = filename.rsplit('.', 1) if '.' in filename else (filename, '')
        counter = 2
        while True:
            candidate = _('%(stem)s (%(counter)s)', stem=stem, counter=counter)
            if extension:
                candidate = '%s.%s' % (candidate, extension)
            if candidate not in used_filenames:
                used_filenames.add(candidate)
                return candidate
            counter += 1