use chrono::Utc;
use std::fs::{File, OpenOptions};
use std::io::Write;
use std::path::PathBuf;
use std::sync::Mutex;

pub struct AuditLog {
    log_file: Mutex<File>,
    log_path: PathBuf,
}

impl AuditLog {
    pub fn new(log_path: &str) -> anyhow::Result<Self> {
        let path = PathBuf::from(log_path);

        // 确保日志目录存在
        if let Some(parent) = path.parent() {
            std::fs::create_dir_all(parent)?;
        }

        // 打开日志文件（追加模式）
        let file = OpenOptions::new().create(true).append(true).open(&path)?;

        Ok(Self {
            log_file: Mutex::new(file),
            log_path: path,
        })
    }

    pub fn log_operation(&self, user_id: &str, operation: &str, path: &str, result: &str) {
        let timestamp = Utc::now().format("%Y-%m-%dT%H:%M:%SZ");
        let entry = format!(
            "[{}] user={} operation={} path=\"{}\" result={}\n",
            timestamp, user_id, operation, path, result
        );

        // 写入日志文件
        if let Ok(mut file) = self.log_file.lock() {
            if let Err(e) = file.write_all(entry.as_bytes()) {
                log::error!("Failed to write audit log: {}", e);
            }
        }

        // 同时输出到标准日志
        log::info!(
            "Audit: user={} operation={} path=\"{}\" result={}",
            user_id,
            operation,
            path,
            result
        );
    }

    pub fn log_error(&self, user_id: &str, operation: &str, path: &str, error: &str) {
        self.log_operation(user_id, operation, path, &format!("error: {}", error));
    }

    pub fn log_success(&self, user_id: &str, operation: &str, path: &str) {
        self.log_operation(user_id, operation, path, "success");
    }

    pub fn get_log_path(&self) -> &PathBuf {
        &self.log_path
    }
}

impl Clone for AuditLog {
    fn clone(&self) -> Self {
        // Clone时重新打开文件
        Self::new(&self.log_path.to_string_lossy()).unwrap_or_else(|_| {
            // 如果失败，使用临时路径
            Self::new("/tmp/sftp_audit_fallback.log").unwrap()
        })
    }
}