use crate::qr::QrCode;

/// 终端 ASCII 渲染：██ 表示暗模块，"  " 表示亮模块
pub fn render_ascii(qr: &QrCode, invert: bool) -> String {
    let size = qr.size() as usize;
    let margin = qr.margin as usize;
    let total = size + 2 * margin;

    let dark_char = if invert { "  " } else { "██" };
    let light_char = if invert { "██" } else { "  " };

    let mut result = String::new();
    for y in 0..total {
        for x in 0..total {
            let mx = x.saturating_sub(margin);
            let my = y.saturating_sub(margin);
            let is_dark = if mx < size && my < size {
                qr.modules()[my][mx]
            } else {
                false
            };
            result.push_str(if is_dark { dark_char } else { light_char });
        }
        result.push('\n');
    }
    result
}