use std::fs;
use std::path::Path;

fn main() {
    // Compile protobuf files for RustDesk protocol
    compile_protos();

    // Generate minimal secrets module
    generate_secrets();

    // Rerun if the script itself changes
    println!("cargo:rerun-if-changed=build.rs");
    println!("cargo:rerun-if-changed=protos/rendezvous.proto");
    println!("cargo:rerun-if-changed=protos/message.proto");
}

/// Compile protobuf files using protobuf-codegen (same as RustDesk server)
fn compile_protos() {
    let out_dir = std::path::PathBuf::from(std::env::var("OUT_DIR").unwrap());
    let protos_dir = out_dir.join("protos");
    std::fs::create_dir_all(&protos_dir).unwrap();

    protobuf_codegen::Codegen::new()
        .pure()
        .out_dir(&protos_dir)
        .inputs(["protos/rendezvous.proto", "protos/message.proto"])
        .include("protos")
        .customize(protobuf_codegen::Customize::default().tokio_bytes(true))
        .run()
        .expect("Failed to compile protobuf files");

    // Generate mod.rs for the protos module
    let mod_content = r#"pub mod rendezvous;
pub mod message;
"#;
    std::fs::write(protos_dir.join("mod.rs"), mod_content).unwrap();
}

/// Generate minimal secrets module with Google STUN server hardcoded
fn generate_secrets() {
    let out_dir = std::env::var("OUT_DIR").unwrap();
    let dest_path = Path::new(&out_dir).join("secrets_generated.rs");

    // Generate the secrets module - no public servers provided
    let code = r#"// Auto-generated secrets module
// DO NOT EDIT - This file is generated by build.rs

/// ICE server configuration (for WebRTC NAT traversal)
pub mod ice {
    /// Google public STUN server URL (hardcoded)
    pub const STUN_SERVER: &str = "stun:stun.l.google.com:19302";
}

/// RustDesk public server configuration - NOT PROVIDED
pub mod rustdesk {
    /// Public RustDesk ID server - NOT PROVIDED
    pub const PUBLIC_SERVER: &str = "";

    /// Public key for the RustDesk server - NOT PROVIDED
    pub const PUBLIC_KEY: &str = "";

    /// Relay server authentication key - NOT PROVIDED
    pub const RELAY_KEY: &str = "";

    /// Always returns false
    pub const fn has_public_server() -> bool {
        false
    }
}
"#;

    fs::write(&dest_path, code).expect("Failed to write secrets_generated.rs");
}