use bat_adapters::unity::RawAssetBundle;
use bat_adapters::unity::{Unity2021_3Adapter, UnityAdapterRegistry};

fn push_c_string(data: &mut Vec<u8>, value: &str) {
    data.extend_from_slice(value.as_bytes());
    data.push(0);
}

fn push_u16(data: &mut Vec<u8>, value: u16) {
    data.extend_from_slice(&value.to_be_bytes());
}

fn push_u32(data: &mut Vec<u8>, value: u32) {
    data.extend_from_slice(&value.to_be_bytes());
}

fn push_i32(data: &mut Vec<u8>, value: i32) {
    data.extend_from_slice(&value.to_be_bytes());
}

fn push_u64(data: &mut Vec<u8>, value: u64) {
    data.extend_from_slice(&value.to_be_bytes());
}

fn align(data: &mut Vec<u8>, alignment: usize) {
    let remainder = data.len() % alignment;
    if remainder != 0 {
        data.resize(data.len() + alignment - remainder, 0);
    }
}

fn synthetic_minimal_unityfs_bundle() -> Vec<u8> {
    let mut blocks_info = Vec::new();
    blocks_info.extend_from_slice(&[0; 16]);
    push_i32(&mut blocks_info, 1);
    push_u32(&mut blocks_info, 4);
    push_u32(&mut blocks_info, 4);
    push_u16(&mut blocks_info, 0);
    push_i32(&mut blocks_info, 1);
    push_u64(&mut blocks_info, 0);
    push_u64(&mut blocks_info, 4);
    push_u32(&mut blocks_info, 0);
    push_c_string(&mut blocks_info, "SYNTHETIC-DEMO-CAB");

    let mut data = Vec::new();
    push_c_string(&mut data, "UnityFS");
    push_u32(&mut data, 8);
    push_c_string(&mut data, "5.x.x");
    push_c_string(&mut data, "2021.3.56f2");
    push_u64(&mut data, 0);
    push_u32(&mut data, blocks_info.len() as u32);
    push_u32(&mut data, blocks_info.len() as u32);
    push_u32(&mut data, 0);
    align(&mut data, 16);
    data.extend_from_slice(&blocks_info);
    data.extend_from_slice(b"data");

    let total_size = data.len() as u64;
    let total_size_offset = b"UnityFS\0".len() + 4 + b"5.x.x\0".len() + b"2021.3.56f2\0".len();
    data[total_size_offset..total_size_offset + 8].copy_from_slice(&total_size.to_be_bytes());
    data
}

fn main() {
    println!("🎮 BlueArchiveToolkit - Unity 适配器演示");
    println!("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━");

    // 创建 Unity Adapter
    let adapter = Unity2021_3Adapter::new();
    println!("✅ Unity Adapter: {}", adapter.name());
    println!("   支持版本: 2021.3.0 - 2021.3.99");

    // 合成最小 UnityFS 文件，仅用于演示版本检测和适配器选择。
    println!("\n📦 测试 Unity 版本检测...");
    let bundle = RawAssetBundle {
        data: synthetic_minimal_unityfs_bundle(),
        path: Some("synthetic-demo.bundle".to_string()),
    };

    if adapter.can_handle(&bundle) {
        println!("  ✅ 可以处理 Unity 2021.3.56f2");
    } else {
        println!("  ❌ 不支持此版本");
    }

    // 测试 Registry
    println!("\n🔄 测试 Adapter Registry...");
    let registry = UnityAdapterRegistry::with_defaults();
    println!("  注册的适配器数量: {}", registry.count());

    match registry.select_adapter(&bundle) {
        Ok(selected) => {
            println!("  ✅ 自动选择的适配器: {}", selected.name());
        }
        Err(e) => {
            println!("  ❌ 选择失败: {}", e);
        }
    }

    println!("\n✅ 演示完成！");
    println!("━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━");
}