from odoo import models, _, api, fields
from odoo.exceptions import UserError


class IrAttachment(models.Model):
    _inherit = 'ir.attachment'

    def create(self, vals_list):
        # 1. Get the limit from system parameters (set via res.config.settings)
        # Default to 2048 MB (2 GB) if not set in settings
        max_size_mb = float(self.env['ir.config_parameter'].sudo().get_param(
            'attachment_size.max_attachment_size', default=2048.0
        ))

        # 2. Convert MB to bytes
        max_size_bytes = max_size_mb * 1024 * 1024

        # 3. Validate file size
        for vals in vals_list:
            if vals.get('datas'):
                # Base64 increases size by ~33%, so we check against max_size_bytes * 4 / 3
                if len(vals['datas']) > (max_size_bytes * 4 / 3):
                    raise UserError(_(
                        "File size exceeds the maximum allowed limit of %(max_size)s MB.",
                        max_size=max_size_mb
                    ))

        return super().create(vals_list)


class FileSizeConfigSetting(models.TransientModel):
    _inherit = 'res.config.settings'

    max_attachment_size = fields.Float(
        string="Maximum Attachment Size (MB)",
        config_parameter='attachment_size.max_attachment_size',
        help="Set the maximum size for attachments in MB. Default is 2048 MB (2 GB)."
    )


class Http(models.AbstractModel):
    _inherit = "ir.http"

    @api.model
    def session_info(self):
        session_info = super().session_info()

        # Get the limit from system parameters, default to 2048 MB (2 GB)
        max_size_mb = float(self.env['ir.config_parameter'].sudo().get_param(
            'attachment_size.max_attachment_size', default=2048.0
        ))

        max_attachment_size_bytes = max_size_mb * 1024 * 1024  # Convert MB to Bytes

        # Always update session_info so JS always has a value (no more undefined)
        session_info.update({
            "max_attachment_size": max_attachment_size_bytes,
            "max_size": max_size_mb,
            "max_file_upload_size": max_attachment_size_bytes,
        })

        return session_info