"""多渠道网关配对二维码生成工具。"""

from __future__ import annotations

import io

import qrcode


class PairingQRGenerator:
    def __init__(self, base_url: str | None = None):
        self.base_url = base_url

    def generate_content(
        self,
        code: str,
        channel_type: str,
        account_id: str,
        peer_id: str,
        mode: str = "plain",
    ) -> str:
        """生成二维码编码字符串。"""
        if mode == "plain":
            return code
        base = self.base_url or ""
        if not base:
            return code
        return f"{base}/pairing?code={code}&channel={channel_type}&account={account_id}&peer_id={peer_id}"

    def generate_image(
        self,
        content: str,
        box_size: int = 10,
        border: int = 2,
    ) -> bytes:
        """生成 PNG 格式二维码图片字节。"""
        qr = qrcode.QRCode(
            version=None,
            error_correction=qrcode.constants.ERROR_CORRECT_M,
            box_size=box_size,
            border=border,
        )
        qr.add_data(content)
        qr.make(fit=True)
        image = qr.make_image(fill_color="black", back_color="white")
        buffer = io.BytesIO()
        image.save(buffer, format="PNG")
        return buffer.getvalue()