//! Age backend encryption example.
//!
//! Demonstrates basic encryption/decryption using the Age backend.
//!
//! # Usage
//!
//! ```bash
//! # Ensure Age key exists
//! age-keygen -o ~/.age/key.txt
//!
//! # Run example
//! cargo run --example age_backend --features age
//! ```

use encrypt::{decrypt, encrypt, BackendSpec};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    println!("=== Age Backend Encryption Example ===\n");

    // Create Age backend spec with default key paths (~/.age/key.txt)
    let spec = BackendSpec::age_default();
    println!("Backend: {}", spec.backend_name());
    println!("Using default key paths: ~/.age/key.txt\n");

    // Plaintext secret
    let secret = "my-super-secret-password-123!@#";
    println!("Original secret: {}", secret);

    // Encrypt
    match encrypt(secret, &spec) {
        Ok(ciphertext) => {
            println!("✓ Encrypted successfully");
            println!(
                "Ciphertext (first 80 chars): {}...",
                &ciphertext[..80.min(ciphertext.len())]
            );

            // Decrypt
            match decrypt(&ciphertext, &spec) {
                Ok(plaintext) => {
                    println!("✓ Decrypted successfully");
                    println!("Decrypted secret: {}", plaintext);

                    // Verify roundtrip
                    if plaintext == secret {
                        println!("\n✓ Roundtrip successful - plaintext matches!");
                    } else {
                        println!("\n✗ Roundtrip failed - plaintext mismatch!");
                        return Err("Roundtrip verification failed".into());
                    }
                }
                Err(e) => {
                    println!("✗ Decryption failed: {}", e);
                    return Err(e.into());
                }
            }
        }
        Err(e) => {
            println!("✗ Encryption failed: {}", e);
            println!("\nMake sure Age key exists:");
            println!("  age-keygen -o ~/.age/key.txt");
            return Err(e.into());
        }
    }

    // Example 2: Custom key path
    println!("\n=== Custom Key Path Example ===\n");

    let custom_key_path = "/tmp/age-test-key.txt";
    let spec_custom = BackendSpec::age(custom_key_path);

    println!("Backend: {}", spec_custom.backend_name());
    println!("Using custom key path: {}\n", custom_key_path);
    println!("Note: Custom key path does not exist, so encryption would fail");
    println!("To test, generate a key: age-keygen -o {}", custom_key_path);

    Ok(())
}