harmoniis-wallet 0.1.109

//! Persistent configuration and state for cloud mining instances.
//!
//! Stored at `~/.harmoniis/cloud/config.toml` and `~/.harmoniis/cloud/state.toml`.

use anyhow::{Context, Result};
use serde::{Deserialize, Serialize};
use std::path::PathBuf;

/// Persisted user configuration.
#[derive(Debug, Default, Serialize, Deserialize)]
pub struct CloudConfig {
    pub vast_api_key: Option<String>,
    #[serde(default = "default_label")]
    pub default_label: String,
}

fn default_label() -> String {
    "cloudminer".to_string()
}

/// Persisted state for a running cloud mining instance.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct InstanceState {
    pub instance_id: u64,
    pub offer_id: u64,
    pub label: String,
    pub ssh_host: String,
    pub ssh_port: u16,
    pub gpu_name: String,
    pub num_gpus: u32,
    pub cost_per_hour: f64,
    pub started_at: String,
}

/// Multi-instance state file.
#[derive(Debug, Default, Serialize, Deserialize)]
pub struct InstancesFile {
    #[serde(default)]
    pub instances: Vec<InstanceState>,
}

fn cloud_dir() -> PathBuf {
    dirs_next::home_dir()
        .unwrap_or_else(|| PathBuf::from("."))
        .join(".harmoniis")
        .join("cloud")
}

fn config_path() -> PathBuf {
    cloud_dir().join("config.toml")
}

fn state_path() -> PathBuf {
    cloud_dir().join("state.toml")
}

pub fn ssh_key_path() -> PathBuf {
    cloud_dir().join("id_ed25519")
}

pub fn ssh_pubkey_path() -> PathBuf {
    cloud_dir().join("id_ed25519.pub")
}

pub fn load_config() -> Result<CloudConfig> {
    let path = config_path();
    if !path.exists() {
        return Ok(CloudConfig::default());
    }
    let text = std::fs::read_to_string(&path)
        .with_context(|| format!("failed to read {}", path.display()))?;
    toml::from_str(&text).with_context(|| format!("failed to parse {}", path.display()))
}

pub fn save_config(cfg: &CloudConfig) -> Result<()> {
    let dir = cloud_dir();
    std::fs::create_dir_all(&dir)?;
    let text = toml::to_string_pretty(cfg)?;
    std::fs::write(config_path(), text)?;
    Ok(())
}

/// Load all instance states.
pub fn load_instances() -> Result<Vec<InstanceState>> {
    let path = state_path();
    if !path.exists() {
        return Ok(Vec::new());
    }
    let text = std::fs::read_to_string(&path)
        .with_context(|| format!("failed to read {}", path.display()))?;

    // Try new format (InstancesFile with [[instances]])
    if let Ok(file) = toml::from_str::<InstancesFile>(&text) {
        return Ok(file.instances);
    }
    // Backward compat: old single-instance format
    if let Ok(state) = toml::from_str::<InstanceState>(&text) {
        return Ok(vec![state]);
    }
    Ok(Vec::new())
}

/// Backward compat: load first instance (or None).
pub fn load_state() -> Result<Option<InstanceState>> {
    let instances = load_instances()?;
    Ok(instances.into_iter().next())
}

/// Add an instance to the state file.
pub fn add_instance(state: &InstanceState) -> Result<()> {
    let mut instances = load_instances()?;
    instances.push(state.clone());
    save_instances(&instances)
}

/// Remove an instance by ID.
pub fn remove_instance(instance_id: u64) -> Result<()> {
    let mut instances = load_instances()?;
    instances.retain(|s| s.instance_id != instance_id);
    save_instances(&instances)
}

/// Save all instances.
fn save_instances(instances: &[InstanceState]) -> Result<()> {
    let dir = cloud_dir();
    std::fs::create_dir_all(&dir)?;
    let file = InstancesFile {
        instances: instances.to_vec(),
    };
    let text = toml::to_string_pretty(&file)?;
    std::fs::write(state_path(), text)?;
    Ok(())
}

/// Backward compat: save single instance (replaces all).
pub fn save_state(state: &InstanceState) -> Result<()> {
    save_instances(std::slice::from_ref(state))
}

/// Remove all instance state.
pub fn clear_state() -> Result<()> {
    let path = state_path();
    if path.exists() {
        std::fs::remove_file(&path)?;
    }
    Ok(())
}

// ── Concurrency guard ─────────────────────────────────────────────────────

/// Exclusive file lock for cloud start operations.
/// Prevents two terminals from starting instances concurrently.
/// Released automatically when dropped.
pub struct StartLockGuard {
    _file: std::fs::File,
}

/// Acquire an exclusive lock for cloud start.
/// Returns Err if another `cloud start` is already in progress.
pub fn acquire_start_lock() -> Result<StartLockGuard> {
    let dir = cloud_dir();
    std::fs::create_dir_all(&dir)?;
    let lock_path = dir.join("start.lock");
    let file = std::fs::File::create(&lock_path).context("failed to create start.lock")?;

    #[cfg(unix)]
    {
        use std::os::unix::io::AsRawFd;
        let ret = unsafe { libc::flock(file.as_raw_fd(), libc::LOCK_EX | libc::LOCK_NB) };
        if ret != 0 {
            anyhow::bail!(
                "Another `cloud start` is already in progress.\n\
                 If this is a stale lock, remove ~/.harmoniis/cloud/start.lock"
            );
        }
    }

    Ok(StartLockGuard { _file: file })
}

#[cfg(unix)]
impl Drop for StartLockGuard {
    fn drop(&mut self) {
        use std::os::unix::io::AsRawFd;
        unsafe { libc::flock(self._file.as_raw_fd(), libc::LOCK_UN) };
    }
}

// ── API key resolution ────────────────────────────────────────────────────

/// Resolve the API key from config, env, or prompt.
/// Resolve the Vast.ai API key from config, env, or interactive prompt.
///
/// Resolution order:
/// 1. Config file (`~/.harmoniis/cloud/config.toml`)
/// 2. `VAST_API_KEY` environment variable
/// 3. Interactive prompt (saved to config for future use)
pub fn resolve_api_key(cfg: &CloudConfig) -> Result<String> {
    if let Some(key) = &cfg.vast_api_key {
        if !key.is_empty() {
            return Ok(key.clone());
        }
    }
    if let Ok(key) = std::env::var("VAST_API_KEY") {
        if !key.is_empty() {
            return Ok(key);
        }
    }
    // Interactive prompt — ask the user for the key and persist it.
    prompt_and_save_api_key()
}

fn prompt_and_save_api_key() -> Result<String> {
    println!("Vast.ai API key not found.");
    println!();
    println!("To get your API key:");
    println!("  1. Register at https://cloud.vast.ai");
    println!("  2. Add credits (Account → Billing → Add Credit)");
    println!("  3. Copy API key from Account → API Key (sidebar)");
    println!();
    print!("Paste your Vast.ai API key: ");
    use std::io::Write;
    std::io::stdout().flush()?;

    let mut key = String::new();
    std::io::stdin().read_line(&mut key)?;
    let key = key.trim().to_string();

    if key.is_empty() {
        anyhow::bail!("No API key provided.");
    }

    // Persist to config
    let mut cfg = load_config()?;
    cfg.vast_api_key = Some(key.clone());
    save_config(&cfg)?;
    println!("API key saved to ~/.harmoniis/cloud/config.toml");
    println!();

    Ok(key)
}