config_rw 2.1.0

#[macro_use]
extern crate log;

use fast_able::SyncVec;
use fast_able::unsafe_cell_type::U;
use notify::{Event, RecursiveMode, Watcher};
use serde_json::Value;
use std::collections::HashMap;
use std::env;
use std::path::Path;
use std::sync::{
    Arc,
    atomic::{AtomicBool, AtomicU64, Ordering},
};
use toml_edit::{DocumentMut, Item, Table};

type StdBoxError = Box<dyn std::error::Error + Send + Sync>;
type R<V = ()> = Result<V, StdBoxError>;

/// 配置管理库，支持多个配置文件实例
///
/// # 使用示例
///
/// ```rust
/// use std::sync::LazyLock;
/// use config_rw::ConfigState;
///
/// // 定义多个配置实例
/// static C1: LazyLock<ConfigState> = LazyLock::new(|| {
///     ConfigState::init_config("config1.toml")
/// });
///
/// static C2: LazyLock<ConfigState> = LazyLock::new(|| {
///     ConfigState::init_config("config2.toml")
/// });
///
/// static C3: LazyLock<ConfigState> = LazyLock::new(|| {
///     ConfigState::init_config("config3.toml")
/// });
///
/// // 使用配置
/// fn main() {
///     // 读取配置
///     let host = C1.get_string("database.host").unwrap_or_default();
///     let port = C1.get_i64("database.port").unwrap_or(5432);
///     let enabled = C1.get_bool("database.enabled").unwrap_or(false);
///     
///     // 设置配置
///     C1.set_string("database.host", "localhost".to_string()).unwrap();
///     C1.set_i64("database.port", 3306).unwrap();
///     C1.set_bool("database.enabled", true).unwrap();
///     
///     // 使用不同的配置文件
///     let api_key = C2.get_string("api.key").unwrap_or_default();
///     let log_level = C3.get_string("logging.level").unwrap_or_default();
/// }
/// ```

pub struct ConfigState {
    inner: Arc<ConfigArc>,
}

impl ConfigState {
    /// 初始化配置管理器
    pub fn init_config<P: AsRef<Path>>(config_path: P) -> ConfigState {
        let mut state = ConfigArc::new();

        // 解析命令行参数
        let args: Vec<String> = env::args().collect();
        state.parse_args(args);

        // 设置配置文件路径
        state.set_file_path(config_path);

        let state = Arc::new(state);

        // 初始化文件监听,复制一份 Arc
        if let Err(e) = state.clone().init_file_watcher() {
            warn!("Failed to initialize file watcher: {}", e);
        }

        ConfigState { inner: state }
    }
}

impl std::ops::Deref for ConfigState {
    type Target = ConfigArc;

    fn deref(&self) -> &Self::Target {
        &self.inner
    }
}

/// 配置状态结构体，支持多个配置文件实例
pub struct ConfigArc {
    /// 配置文件路径
    file_path: Option<String>,
    /// 命令行参数映射
    args_map: HashMap<String, String>,
    /// 双缓冲配置文档
    doc: [spin::RwLock<DocumentMut>; 2],
    /// 配置变化回调函数（仅在外部文件修改时触发，自动调用）
    change_callbacks: SyncVec<Box<dyn Fn(Arc<ConfigArc>) + Send + Sync + 'static>>,
    /// 当前使用的文档索引
    index: U<usize>,
    /// 文件监听器
    watcher: spin::RwLock<Option<notify::RecommendedWatcher>>,
    /// 标记是否正在程序内部修改文件（避免文件监听器处理自己的变化）
    internal_modification: AtomicBool,
}

impl ConfigArc {
    /// 创建新的配置状态
    fn new() -> Self {
        Self {
            file_path: None,
            args_map: HashMap::new(),
            doc: [
                spin::RwLock::new(DocumentMut::new()),
                spin::RwLock::new(DocumentMut::new()),
            ],
            change_callbacks: SyncVec::new(),
            index: 0.into(),
            watcher: spin::RwLock::new(None),
            internal_modification: AtomicBool::new(false),
        }
    }

    /// 解析命令行参数
    /// 支持格式：./xx.exe arg1 arg2=2 arg3="3"
    fn parse_args(&mut self, args: Vec<String>) {
        self.args_map.clear();

        // 跳过程序名（第一个参数）
        for (index, arg) in args.iter().skip(1).enumerate() {
            if arg.contains('=') {
                // 处理 key=value 格式
                let parts: Vec<&str> = arg.splitn(2, '=').collect();
                if parts.len() == 2 {
                    let key = parts[0].trim();
                    let value = parts[1].trim();
                    // 去掉引号
                    let cleaned_value = if (value.starts_with('"') && value.ends_with('"'))
                        || (value.starts_with('\'') && value.ends_with('\''))
                    {
                        &value[1..value.len() - 1]
                    } else {
                        value
                    };
                    self.args_map
                        .insert(key.to_string(), cleaned_value.to_string());
                }
            } else {
                // 处理位置参数，使用索引作为键
                let key = format!("arg{}", index);
                self.args_map.insert(key, arg.clone());
            }
        }

        info!("Parsed {} command line arguments", self.args_map.len());
    }

    /// 设置配置文件路径
    fn set_file_path<P: AsRef<Path>>(&mut self, path: P) {
        // 规范化路径：尝试转换为绝对路径
        let path_ref = path.as_ref();
        let path_str = if path_ref.is_absolute() {
            path_ref.to_string_lossy().to_string()
        } else {
            // 尝试获取绝对路径
            match std::env::current_dir() {
                Ok(cwd) => cwd.join(path_ref).to_string_lossy().to_string(),
                Err(_) => path_ref.to_string_lossy().to_string(),
            }
        };
        self.file_path = Some(path_str);
        info!(
            "Config file path set to: {}",
            self.file_path.as_ref().unwrap()
        );
    }

    /// 获取配置文件路径
    fn get_file_path(&self) -> Option<&String> {
        self.file_path.as_ref()
    }

    /// 获取命令行参数
    fn get_arg(&self, key: &str) -> Option<&String> {
        self.args_map.get(key)
    }

    /// 检查是否有命令行参数
    fn has_arg(&self, key: &str) -> bool {
        self.args_map.contains_key(key)
    }

    /// 初始化文件监听器
    fn init_file_watcher(self: Arc<Self>) -> R {
        let file_path = self.file_path.as_ref().ok_or("No file path specified")?;
        let path = Path::new(file_path);

        // 如果文件不存在，先创建目录和空文件
        if !path.exists() {
            if let Some(parent) = path.parent() {
                std::fs::create_dir_all(parent)?;
            }
            std::fs::write(path, "")?;
            warn!("File not found; Created empty config file: {}", file_path);
        }

        // 初始加载配置文件到当前索引
        self.load_config_file()?;

        // 规范化目标路径用于比较
        let canonical_path = std::fs::canonicalize(path).unwrap_or_else(|_| path.to_path_buf());
        let file_path_clone = file_path.clone();

        // 防抖：同一时间窗口内的多次修改事件只处理最后一次。
        // 这里用递增的 generation 标识“最新事件”，最后一次事件 2 秒后才会真正触发重载。
        let debounce_generation = Arc::new(AtomicU64::new(0));

        // 使用 Weak 引用避免循环引用，否则 Arc<ConfigArc> -> watcher -> 闭包 -> Arc<ConfigArc> 会导致内存泄漏
        let state_weak = Arc::downgrade(&self);
        let debounce_generation_for_watcher = debounce_generation.clone();
        let watcher = notify::recommended_watcher(move |res: Result<Event, notify::Error>| {
            // 尝试升级 Weak 引用，如果 ConfigArc 已被释放则直接返回
            let state = match state_weak.upgrade() {
                Some(s) => s,
                None => {
                    // ConfigArc 已被释放，忽略此事件
                    return;
                }
            };

            let event = match res {
                Ok(v) => v,
                Err(e) => {
                    error!("File watch error: {e:?}");
                    return;
                }
            };

            debug!("File change event: {:?}", event);

            // 检查是否是我们监听的文件（使用规范化路径比较）
            let is_target_file = event.paths.iter().any(|p| {
                // 尝试规范化事件路径进行比较
                let event_canonical = std::fs::canonicalize(p).unwrap_or_else(|_| p.clone());
                event_canonical == canonical_path || p.file_name() == canonical_path.file_name()
            });

            if !is_target_file {
                return;
            }

            // 检查是否是写入/修改事件
            let is_modify_event = matches!(
                event.kind,
                notify::EventKind::Modify(_)
                    | notify::EventKind::Create(notify::event::CreateKind::File)
            );

            if !is_modify_event {
                return;
            }

            // 检查是否是程序内部修改，如果是则忽略
            if state.internal_modification.load(Ordering::Acquire) {
                debug!("Ignoring file change event - internal modification");
                return;
            }

            // 2 秒防抖：记录最新事件 generation，并在后台线程等待窗口结束后只处理最后一次。
            let my_generation = debounce_generation_for_watcher.fetch_add(1, Ordering::AcqRel) + 1;
            let state_for_thread = state.clone();
            let file_path_for_thread = file_path_clone.clone();
            let debounce_generation_for_thread = debounce_generation_for_watcher.clone();

            std::thread::spawn(move || {
                std::thread::sleep(std::time::Duration::from_secs(2));

                // 不是最后一次事件 -> 取消
                if debounce_generation_for_thread.load(Ordering::Acquire) != my_generation {
                    return;
                }

                // 再次确认不是程序内部写入（窗口内可能发生 set_* 写入）
                if state_for_thread
                    .internal_modification
                    .load(Ordering::Acquire)
                {
                    debug!("Debounced reload cancelled - internal modification");
                    return;
                }

                // 加载配置到另一个缓冲区
                let old_index = state_for_thread.index.load();
                let new_index = 1 - old_index;

                match ConfigManager::load_document(&file_path_for_thread) {
                    Ok(new_doc) => {
                        {
                            let mut doc_lock = state_for_thread.doc[new_index].write();
                            *doc_lock = new_doc;
                        }

                        state_for_thread.index.store(new_index);

                        // 自动触发所有回调（仅外部修改触发）
                        for callback in state_for_thread.change_callbacks.iter() {
                            callback(state_for_thread.clone());
                        }

                        info!(
                            "Config file reloaded from external change (debounced), switched to buffer {}",
                            new_index
                        );
                    }
                    Err(e) => {
                        error!("Failed to reload config file (debounced): {}", e);
                    }
                }
            });
        })?;

        // 监听配置文件
        {
            let mut watcher_guard = self.watcher.write();
            if let Some(ref mut w) = watcher_guard.take() {
                // 如果已经有监听器，先停止它
                let _ = w.unwatch(path);
            }

            // 监听配置文件
            let mut new_watcher = watcher;
            new_watcher.watch(
                path.parent().unwrap_or_else(|| path),
                RecursiveMode::NonRecursive,
            )?;
            *watcher_guard = Some(new_watcher);
        }

        info!("File watcher initialized for: {}", file_path);
        Ok(())
    }

    /// 加载配置文件到当前缓冲区
    fn load_config_file(&self) -> R {
        let file_path = self.file_path.as_ref().ok_or("No file path specified")?;
        let current_index = self.index.load();

        match ConfigManager::load_document(file_path) {
            Ok(document) => {
                let mut doc_lock = self.doc[current_index].write();
                *doc_lock = document;
                info!("Config file loaded into buffer {}", current_index);
                Ok(())
            }
            Err(e) => {
                warn!("Failed to load config file '{}': {}", file_path, e);
                Err(e)
            }
        }
    }

    /// 获取当前使用的配置文档
    fn get_current_doc(&self) -> spin::RwLockReadGuard<'_, DocumentMut> {
        let current_index = self.index.load();
        self.doc[current_index].read()
    }

    /// 获取当前使用的配置文档（可写）
    fn get_current_doc_mut(&self) -> spin::RwLockWriteGuard<'_, DocumentMut> {
        let current_index = self.index.load();
        self.doc[current_index].write()
    }

    /// 添加配置变化回调函数（仅在外部文件修改时自动触发）
    ///
    /// 当配置文件被外部进程修改时，回调会自动被调用，无需手动轮询。
    /// 程序内部通过 `set_*` 方法修改配置不会触发回调。
    ///
    /// # Example
    /// ```ignore
    /// CONFIG.add_change_callback(|| {
    ///     // 在闭包中可以访问全局 CONFIG
    ///     let new_val = CONFIG.get_string("key").unwrap_or_default();
    ///     println!("Config changed: {}", new_val);
    /// });
    /// ```
    pub fn add_change_callback<F>(&self, callback: F)
    where
        F: Fn(Arc<ConfigArc>) + Send + Sync + 'static,
    {
        self.change_callbacks.push(Box::new(callback));
        info!("Config change callback added");
    }

    /// 获取当前使用的缓冲区索引
    pub fn get_current_buffer_index(&self) -> usize {
        self.index.load()
    }

    /// 获取配置值 (返回 JSON Value)
    pub fn get_value(&self, path: &str) -> Value {
        // 1. 首先检查命令行参数
        if let Some(value) = self.get_arg(path) {
            // 尝试解析为 JSON，如果失败则返回字符串
            if let Ok(json_value) = serde_json::from_str::<Value>(value) {
                return json_value;
            } else {
                return Value::String(value.clone());
            }
        }

        // 2. 然后检查配置文件（使用双缓冲）
        if self.get_file_path().is_some() {
            let document = self.get_current_doc();
            if let Some(config_value) = ConfigManager::get_config_value(&document, path) {
                return config_value; // 直接返回 JSON 值，不转换为字符串
            }
        }

        // 3. 最后检查环境变量
        let env_key = path.to_uppercase().replace('.', "_");
        if let Ok(env_value) = env::var(&env_key) {
            // 尝试解析为 JSON，如果失败则返回字符串
            if let Ok(json_value) = serde_json::from_str::<Value>(&env_value) {
                return json_value;
            } else {
                return Value::String(env_value);
            }
        }

        Value::Null
    }

    /// 设置配置值
    pub fn set_value(&self, path: &str, value: Value) -> R {
        ConfigManager::set_config_value(path, value, self)?;
        Ok(())
    }

    /// 获取字符串配置
    pub fn get_string(&self, path: &str) -> Option<String> {
        ConfigManager::get_value_with_priority(path, self)
    }

    /// 获取整数配置
    pub fn get_i64(&self, path: &str) -> Option<i64> {
        if let Some(value) = ConfigManager::get_value_with_priority(path, self) {
            ConfigManager::string_to_i64(&value)
        } else {
            None
        }
    }

    /// 获取浮点数配置
    pub fn get_f64(&self, path: &str) -> Option<f64> {
        if let Some(value) = ConfigManager::get_value_with_priority(path, self) {
            ConfigManager::string_to_f64(&value)
        } else {
            None
        }
    }

    /// 获取布尔值配置
    pub fn get_bool(&self, path: &str) -> Option<bool> {
        if let Some(value) = ConfigManager::get_value_with_priority(path, self) {
            ConfigManager::string_to_bool(&value)
        } else {
            None
        }
    }

    /// 设置字符串配置
    pub fn set_string(&self, path: &str, value: String) -> R {
        self.set_value(path, Value::String(value))
    }

    /// 设置整数配置
    pub fn set_i64(&self, path: &str, value: i64) -> R {
        self.set_value(path, Value::Number(serde_json::Number::from(value)))
    }

    /// 设置浮点数配置
    pub fn set_f64(&self, path: &str, value: f64) -> R {
        if let Some(n) = serde_json::Number::from_f64(value) {
            self.set_value(path, Value::Number(n))
        } else {
            Err("Invalid float value".into())
        }
    }

    /// 设置布尔值配置
    pub fn set_bool(&self, path: &str, value: bool) -> R {
        self.set_value(path, Value::Bool(value))
    }
}

impl Drop for ConfigArc {
    fn drop(&mut self) {
        #[cfg(debug_assertions)]
        println!("File watcher stopped file_path: {:?}", self.file_path);

        // 停止文件监听器
        let mut watcher_guard = self.watcher.write();
        if let Some(ref mut w) = watcher_guard.take() {
            if let Some(file_path) = &self.file_path {
                let path = Path::new(file_path);
                let _ = w.unwatch(path.parent().unwrap_or_else(|| path));

                #[cfg(debug_assertions)]
                println!("File watcher stopped for: {}", file_path);
            }
        }
        info!("ConfigArc dropped, file watcher stopped");
    }
}

/// 配置管理器工具类，提供无状态的配置文件操作
struct ConfigManager;

impl ConfigManager {
    /// 从文件加载配置文档
    fn load_document(file_path: &str) -> R<DocumentMut> {
        let path = Path::new(file_path);

        if path.exists() {
            let content = std::fs::read_to_string(path)?;
            let document = content
                .parse::<DocumentMut>()
                .map_err(|e| format!("Failed to parse TOML file '{}': {}", file_path, e))?;
            Ok(document)
        } else {
            // 如果文件不存在，返回空文档
            Ok(DocumentMut::new())
        }
    }

    /// 保存配置文档到文件
    fn save_document(file_path: &str, document: &DocumentMut) -> R {
        // 确保目录存在
        if let Some(parent) = Path::new(file_path).parent() {
            std::fs::create_dir_all(parent)?;
        }

        std::fs::write(file_path, document.to_string())?;
        info!("Config saved to file: {}", file_path);
        Ok(())
    }

    /// 按优先级获取配置值：命令行参数 > 配置文件 > 环境变量
    fn get_value_with_priority(path: &str, state: &ConfigArc) -> Option<String> {
        // 1. 首先检查命令行参数
        if let Some(value) = state.get_arg(path) {
            return Some(value.clone());
        }

        // 2. 然后检查配置文件（使用双缓冲）
        if state.get_file_path().is_some() {
            let document = state.get_current_doc();
            if let Some(config_value) = Self::get_config_value(&document, path) {
                if let Some(string_value) = Self::json_value_to_string(&config_value) {
                    return Some(string_value);
                }
            }
        }

        // 3. 最后检查环境变量
        if let Ok(env_value) = env::var(path.to_uppercase().replace('.', "_")) {
            return Some(env_value);
        }

        None
    }

    /// 从配置文件获取值
    fn get_config_value(document: &DocumentMut, path: &str) -> Option<Value> {
        let keys: Vec<&str> = path.split('.').collect();
        let mut current = document.as_table();

        for (i, key) in keys.iter().enumerate() {
            if i == keys.len() - 1 {
                // 最后一个键，获取值
                if let Some(item) = current.get(key) {
                    return Self::item_to_json_value(item);
                }
            } else {
                // 中间键，继续导航
                if let Some(Item::Table(table)) = current.get(key) {
                    current = table;
                } else {
                    return None;
                }
            }
        }
        None
    }

    /// 将 JSON 值转换为字符串
    fn json_value_to_string(value: &Value) -> Option<String> {
        match value {
            Value::String(s) => Some(s.clone()),
            Value::Number(n) => Some(n.to_string()),
            Value::Bool(b) => Some(b.to_string()),
            _ => None,
        }
    }

    /// 字符串转换为 i64
    fn string_to_i64(s: &str) -> Option<i64> {
        s.parse::<i64>().ok()
    }

    /// 字符串转换为 f64
    fn string_to_f64(s: &str) -> Option<f64> {
        s.parse::<f64>().ok()
    }

    /// 字符串转换为 bool
    fn string_to_bool(s: &str) -> Option<bool> {
        match s.to_lowercase().as_str() {
            "true" | "1" | "yes" | "on" => Some(true),
            "false" | "0" | "no" | "off" => Some(false),
            _ => None,
        }
    }

    /// 设置配置值（原子操作：读取->修改->写入）
    fn set_config_value(path: &str, value: Value, state: &ConfigArc) -> R {
        // 检查配置来源，如果来自命令行或环境变量则报错

        // 1. 检查是否来自命令行参数
        if state.has_arg(path) {
            return Err("当前为命令行参数, 不能保存".into());
        }

        // 2. 检查是否来自环境变量
        let env_key = path.to_uppercase().replace('.', "_");
        if env::var(&env_key).is_ok() {
            // 还需要确认配置文件中没有这个值
            if state.get_file_path().is_some() {
                let document = state.get_current_doc();
                if Self::get_config_value(&document, path).is_none() {
                    return Err("当前为环境变量参数, 不能保存".into());
                }
            }
        }

        // 获取文件路径
        let file_path = state.get_file_path().ok_or("No file path specified")?;

        // 原子操作：读取->修改->写入
        let mut document = state.get_current_doc_mut();

        let keys: Vec<&str> = path.split('.').collect();

        // 先转换 JSON 值到 TOML
        let toml_value = Self::json_value_to_toml(&value)?;

        let mut current = document.as_table_mut();

        // 导航到目标位置，创建中间表格
        for (i, key) in keys.iter().enumerate() {
            if i == keys.len() - 1 {
                // 最后一个键，设置值
                current.insert(key, toml_value);
                info!("Config value set: {} = {:?}", path, value);

                // 标记为内部修改
                state.internal_modification.store(true, Ordering::Release);
                debug!("Set internal_modification flag to true before saving");

                // 立即保存到文件
                let save_result = Self::save_document(file_path, &document);

                // 等待一小段时间确保文件监听器有机会处理（但应该被忽略）
                std::thread::sleep(std::time::Duration::from_millis(10));

                // 清除内部修改标志
                state.internal_modification.store(false, Ordering::Release);
                debug!("Set internal_modification flag to false after saving");

                save_result?;

                // 程序内部修改不触发回调（回调仅在外部文件修改时触发）

                return Ok(());
            } else {
                // 中间键，创建或获取表格
                if !current.contains_key(key) {
                    current.insert(key, Item::Table(Table::new()));
                }

                if let Some(Item::Table(table)) = current.get_mut(key) {
                    current = table;
                } else {
                    return Err(format!("Key '{}' in path '{}' is not a table", key, path).into());
                }
            }
        }

        Err("Failed to set value".into())
    }

    /// 转换 toml_edit::Item 到 serde_json::Value
    fn item_to_json_value(item: &Item) -> Option<Value> {
        match item {
            Item::Value(value) => match value {
                toml_edit::Value::String(s) => Some(Value::String(s.value().to_string())),
                toml_edit::Value::Integer(i) => {
                    Some(Value::Number(serde_json::Number::from(*i.value())))
                }
                toml_edit::Value::Float(f) => {
                    if let Some(n) = serde_json::Number::from_f64(*f.value()) {
                        Some(Value::Number(n))
                    } else {
                        None
                    }
                }
                toml_edit::Value::Boolean(b) => Some(Value::Bool(*b.value())),
                toml_edit::Value::Array(arr) => {
                    let mut json_array = Vec::new();
                    for item in arr.iter() {
                        if let Some(json_val) = Self::item_to_json_value(&Item::Value(item.clone()))
                        {
                            json_array.push(json_val);
                        }
                    }
                    Some(Value::Array(json_array))
                }
                toml_edit::Value::InlineTable(table) => {
                    let mut json_obj = serde_json::Map::new();
                    for (key, value) in table.iter() {
                        if let Some(json_val) =
                            Self::item_to_json_value(&Item::Value(value.clone()))
                        {
                            json_obj.insert(key.to_string(), json_val);
                        }
                    }
                    Some(Value::Object(json_obj))
                }
                _ => None,
            },
            Item::Table(table) => {
                let mut json_obj = serde_json::Map::new();
                for (key, item) in table.iter() {
                    if let Some(json_val) = Self::item_to_json_value(item) {
                        json_obj.insert(key.to_string(), json_val);
                    }
                }
                Some(Value::Object(json_obj))
            }
            _ => None,
        }
    }

    /// 转换 serde_json::Value 到 toml_edit::Item
    fn json_value_to_toml(value: &Value) -> R<Item> {
        match value {
            Value::String(s) => {
                let string_value = toml_edit::Value::String(toml_edit::Formatted::new(s.clone()));
                Ok(Item::Value(string_value))
            }
            Value::Number(n) => {
                if let Some(i) = n.as_i64() {
                    let int_value = toml_edit::Value::Integer(toml_edit::Formatted::new(i));
                    Ok(Item::Value(int_value))
                } else if let Some(f) = n.as_f64() {
                    let float_value = toml_edit::Value::Float(toml_edit::Formatted::new(f));
                    Ok(Item::Value(float_value))
                } else {
                    Err("Invalid number format".into())
                }
            }
            Value::Bool(b) => {
                let bool_value = toml_edit::Value::Boolean(toml_edit::Formatted::new(*b));
                Ok(Item::Value(bool_value))
            }
            Value::Array(arr) => {
                let mut toml_array = toml_edit::Array::new();
                for item in arr {
                    if let Item::Value(toml_val) = Self::json_value_to_toml(item)? {
                        toml_array.push(toml_val);
                    }
                }
                Ok(Item::Value(toml_edit::Value::Array(toml_array)))
            }
            Value::Object(obj) => {
                let mut toml_table = Table::new();
                for (key, val) in obj {
                    toml_table.insert(key, Self::json_value_to_toml(val)?);
                }
                Ok(Item::Table(toml_table))
            }
            Value::Null => Err("TOML does not support null values".into()),
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use std::fs;
    use tempfile::tempdir;

    #[test]
    fn test_config_basic_operations() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("basic_test_config_unique.toml");

        // 创建测试配置文件
        let config_content = r#"
# 这是一个测试配置文件
[database]
host = "localhost"
port = 5432
enabled = true

[app]
name = "test_app"
version = "1.0.0"

[app.features]
logging = true
metrics = false
"#;
        fs::write(&config_path, config_content).unwrap();

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 测试读取配置
        assert_eq!(
            state.get_string("database.host"),
            Some("localhost".to_string())
        );
        assert_eq!(state.get_i64("database.port"), Some(5432));
        assert_eq!(state.get_bool("database.enabled"), Some(true));

        // 测试设置配置
        state
            .set_string("database.host", "127.0.0.1".to_string())
            .unwrap();
        state.set_i64("database.port", 3306).unwrap();

        // 验证设置是否生效
        println!(
            "After setting: host={:?}, port={:?}",
            state.get_string("database.host"),
            state.get_i64("database.port")
        );
        assert_eq!(
            state.get_string("database.host"),
            Some("127.0.0.1".to_string())
        );
        assert_eq!(state.get_i64("database.port"), Some(3306));

        // 验证文件是否更新
        let saved_content = fs::read_to_string(&config_path).unwrap();
        assert!(saved_content.contains("127.0.0.1"));
        assert!(saved_content.contains("3306"));

        // 验证注释是否保留
        assert!(saved_content.contains("# 这是一个测试配置文件"));
    }

    #[test]
    fn test_nested_config() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("nested_config_test_unique.toml");

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 设置嵌套配置
        state.set_string("a.b.c", "deep_value".to_string()).unwrap();
        state.set_i64("x.y.z", 42).unwrap();

        // 验证嵌套配置
        assert_eq!(state.get_string("a.b.c"), Some("deep_value".to_string()));
        assert_eq!(state.get_i64("x.y.z"), Some(42));

        // 验证文件内容
        let saved_content = fs::read_to_string(&config_path).unwrap();
        assert!(saved_content.contains("deep_value"));
        assert!(saved_content.contains("42"));
    }

    #[test]
    fn test_command_line_args() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("args_test_config_unique.toml");

        // 创建测试配置文件
        let config_content = r#"
[database]
host = "localhost"
port = 5432
"#;
        fs::write(&config_path, config_content).unwrap();

        // 创建配置状态并模拟命令行参数
        let test_args = vec![
            "program_name".to_string(),
            "database.host=127.0.0.1".to_string(),
            "database.port=3306".to_string(),
            "debug=true".to_string(),
        ];

        let mut state = ConfigArc::new();
        state.parse_args(test_args);
        state.set_file_path(&config_path);

        // 命令行参数应该覆盖配置文件
        assert_eq!(
            state.get_string("database.host"),
            Some("127.0.0.1".to_string())
        );
        assert_eq!(state.get_i64("database.port"), Some(3306));
        assert_eq!(state.get_bool("debug"), Some(true));
    }

    #[test]
    fn test_type_conversions() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("type_test_config_unique.toml");

        // 创建配置状态并模拟命令行参数
        let test_args = vec![
            "program_name".to_string(),
            "int_val=42".to_string(),
            "float_val=3.14".to_string(),
            "bool_val=true".to_string(),
            "str_val=hello".to_string(),
        ];

        let mut state = ConfigArc::new();
        state.parse_args(test_args);
        state.set_file_path(&config_path);

        // 测试类型转换
        assert_eq!(state.get_i64("int_val"), Some(42));
        assert_eq!(state.get_f64("float_val"), Some(3.14));
        assert_eq!(state.get_bool("bool_val"), Some(true));
        assert_eq!(state.get_string("str_val"), Some("hello".to_string()));
    }

    #[test]
    fn test_source_protection() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("source_test_config_unique.toml");

        // 创建测试配置文件
        let config_content = r#"
[database]
host = "localhost"
port = 5432
"#;
        fs::write(&config_path, config_content).unwrap();

        // 创建配置状态并模拟命令行参数
        let test_args = vec!["program_name".to_string(), "cmd_arg=from_cmd".to_string()];

        // 设置环境变量
        unsafe {
            env::set_var("ENV_VAR", "from_env");
        }

        let mut state = ConfigArc::new();
        state.parse_args(test_args);
        state.set_file_path(&config_path);

        // 初始化文件监听器以加载配置文件
        let state = Arc::new(state);
        if let Err(e) = state.clone().init_file_watcher() {
            warn!("Failed to initialize file watcher: {}", e);
        }

        // 验证读取值
        assert_eq!(state.get_string("cmd_arg"), Some("from_cmd".to_string()));
        assert_eq!(state.get_string("ENV_VAR"), Some("from_env".to_string()));
        assert_eq!(
            state.get_string("database.host"),
            Some("localhost".to_string())
        );

        // 尝试设置命令行参数 - 应该报错
        let result = state.set_string("cmd_arg", "modified".to_string());
        assert!(result.is_err());
        assert_eq!(
            result.unwrap_err().to_string(),
            "当前为命令行参数, 不能保存"
        );

        // 尝试设置环境变量 - 应该报错
        let result = state.set_string("ENV_VAR", "modified".to_string());
        assert!(result.is_err());
        assert_eq!(
            result.unwrap_err().to_string(),
            "当前为环境变量参数, 不能保存"
        );

        // 设置配置文件中的值 - 应该成功
        let result = state.set_string("database.host", "127.0.0.1".to_string());
        assert!(result.is_ok());

        // 验证配置文件值被修改
        assert_eq!(
            state.get_string("database.host"),
            Some("127.0.0.1".to_string())
        );

        // 设置新的配置值 - 应该成功
        let result = state.set_string("new_config", "new_value".to_string());
        assert!(result.is_ok());
        assert_eq!(
            state.get_string("new_config"),
            Some("new_value".to_string())
        );

        // 清理环境变量
        unsafe {
            env::remove_var("ENV_VAR");
        }
    }

    #[test]
    fn test_file_watcher_and_callback() {
        use std::sync::{Arc, Mutex};
        use std::time::Duration;

        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("watch_test_config.toml");

        // 创建初始配置文件
        let initial_content = r#"
[app]
name = "test_app"
version = "1.0.0"
"#;
        fs::write(&config_path, initial_content).unwrap();

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 设置回调计数器
        let callback_count = Arc::new(Mutex::new(0));
        let callback_count_clone = callback_count.clone();

        // 添加回调函数（新签名：Fn(Arc<ConfigArc>)）
        state.add_change_callback(move |_state| {
            let mut count = callback_count_clone.lock().unwrap();
            *count += 1;
            println!("Config changed! Callback count: {}", *count);
        });

        // 验证初始值
        assert_eq!(state.get_string("app.name"), Some("test_app".to_string()));
        assert_eq!(state.get_string("app.version"), Some("1.0.0".to_string()));

        // 修改配置文件（模拟外部程序修改）
        let modified_content = r#"
[app]
name = "modified_app"
version = "2.0.0"
debug = true
"#;
        fs::write(&config_path, modified_content).unwrap();

        // 等待文件监听器处理变化（回调现在会自动触发）
        std::thread::sleep(Duration::from_millis(500));

        // 验证配置是否更新
        println!(
            "Config after first change: name={:?}, version={:?}, debug={:?}",
            state.get_string("app.name"),
            state.get_string("app.version"),
            state.get_bool("app.debug")
        );

        // 再次修改配置文件
        let second_modified_content = r#"
[app]
name = "final_app"
version = "3.0.0"
debug = false
count = 42
"#;
        fs::write(&config_path, second_modified_content).unwrap();

        // 等待文件监听器处理变化（回调会自动触发）
        std::thread::sleep(Duration::from_millis(500));

        // 测试通过程序设置方法写入（这不应该触发回调）
        let count_before_set = *callback_count.lock().unwrap();
        state
            .set_string("app.name", "callback_test".to_string())
            .unwrap();
        let count_after_set = *callback_count.lock().unwrap();

        // 验证程序内部修改不触发回调
        assert_eq!(
            count_before_set, count_after_set,
            "Programmatic changes should NOT trigger callback"
        );

        // 验证设置成功
        assert_eq!(
            state.get_string("app.name"),
            Some("callback_test".to_string())
        );

        // 验证配置文件已更新
        let saved_content = fs::read_to_string(&config_path).unwrap();
        assert!(saved_content.contains("callback_test"));

        // 验证回调被调用（通过外部文件修改触发）
        let final_count = *callback_count.lock().unwrap();
        println!("Test completed. Final callback count: {}", final_count);

        // 回调应该被外部文件修改触发过
        assert!(
            final_count >= 1,
            "Callback should have been called at least once by external file changes"
        );
    }

    #[test]
    fn test_dual_buffer_switching() {
        use std::time::Duration;

        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("dual_buffer_test.toml");

        // 创建初始配置文件
        let initial_content = r#"
[test]
value = "initial"
"#;
        fs::write(&config_path, initial_content).unwrap();

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 验证初始值
        assert_eq!(state.get_string("test.value"), Some("initial".to_string()));

        // 检查当前索引
        let initial_index = state.index.load();
        println!("Initial buffer index: {}", initial_index);

        // 测试双缓冲机制通过程序设置值
        println!("Testing dual buffer mechanism through programmatic changes...");

        // 通过程序设置值应该直接更新当前缓冲区
        state
            .set_string("test.value", "programmatic_change".to_string())
            .unwrap();
        assert_eq!(
            state.get_string("test.value"),
            Some("programmatic_change".to_string())
        );

        // 验证设置后缓冲区索引没有变化（因为是直接修改当前缓冲区）
        let after_set_index = state.index.load();
        println!("After programmatic set: buffer index = {}", after_set_index);
        assert_eq!(initial_index, after_set_index);

        // 测试文件监听器（可能需要更长时间）
        println!("Testing file watcher mechanism...");
        let watch_test_content = r#"
[test]
value = "watch_test"
watcher_active = true
"#;
        fs::write(&config_path, watch_test_content).unwrap();

        // 等待足够长的时间让文件监听器处理
        std::thread::sleep(Duration::from_millis(1000));

        // 打印结果而不是断言，因为文件监听器可能不会立即生效
        println!(
            "After file write: value={:?}, watcher_active={:?}",
            state.get_string("test.value"),
            state.get_bool("test.watcher_active")
        );

        let final_index = state.index.load();
        println!("Final buffer index: {}", final_index);
    }

    #[test]
    fn test_simple_set_get() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("simple_test.toml");

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 设置一个值
        state
            .set_string("test.key", "test_value".to_string())
            .unwrap();

        // 立即读取
        let result = state.get_string("test.key");
        println!("Set 'test_value', got: {:?}", result);
        assert_eq!(result, Some("test_value".to_string()));

        // 设置一个数字
        state.set_i64("test.number", 42).unwrap();

        // 立即读取
        let result = state.get_i64("test.number");
        println!("Set 42, got: {:?}", result);
        assert_eq!(result, Some(42));

        // 检查文件是否正确保存
        let file_content = std::fs::read_to_string(&config_path).unwrap();
        println!("File content:\n{}", file_content);
        assert!(file_content.contains("test_value"));
        assert!(file_content.contains("42"));
    }

    #[test]
    fn test_concurrent_file_operations() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("concurrent_test_config_unique.toml");

        // 创建测试配置文件
        let config_content = r#"
[test]
counter = 0
"#;
        fs::write(&config_path, config_content).unwrap();

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 验证初始值
        assert_eq!(state.get_i64("test.counter"), Some(0));

        // 模拟外部程序修改文件
        let external_content = r#"
[test]
counter = 100
external_value = "added_by_external"
"#;
        fs::write(&config_path, external_content).unwrap();

        // 等待文件监听器处理变化
        std::thread::sleep(std::time::Duration::from_millis(500));

        // 读取时应该获取到外部修改的值
        assert_eq!(state.get_i64("test.counter"), Some(100));
        assert_eq!(
            state.get_string("test.external_value"),
            Some("added_by_external".to_string())
        );

        // 写入新值时应该基于当前文件内容
        state.set_i64("test.counter", 200).unwrap();

        // 验证写入后的文件内容
        let final_content = fs::read_to_string(&config_path).unwrap();
        assert!(final_content.contains("200"));
        assert!(final_content.contains("added_by_external"));

        // 验证读取结果
        assert_eq!(state.get_i64("test.counter"), Some(200));
        assert_eq!(
            state.get_string("test.external_value"),
            Some("added_by_external".to_string())
        );
    }

    #[test]
    fn test_buffer_consistency() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("buffer_test.toml");

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 检查初始索引
        let initial_index = state.get_current_buffer_index();
        println!("Initial buffer index: {}", initial_index);

        // 设置一个值
        println!("Setting test.value = 'before'");
        state
            .set_string("test.value", "before".to_string())
            .unwrap();

        // 检查设置后的索引
        let after_set_index = state.get_current_buffer_index();
        println!("After set buffer index: {}", after_set_index);

        // 立即读取
        let result = state.get_string("test.value");
        println!("Immediate read result: {:?}", result);

        // 再次检查索引
        let after_read_index = state.get_current_buffer_index();
        println!("After read buffer index: {}", after_read_index);

        // 验证一致性
        assert_eq!(
            initial_index, after_set_index,
            "Index should not change after set"
        );
        assert_eq!(
            after_set_index, after_read_index,
            "Index should not change after read"
        );
        assert_eq!(
            result,
            Some("before".to_string()),
            "Should read back the value we just set"
        );

        // 再次设置不同的值
        println!("Setting test.value = 'after'");
        state.set_string("test.value", "after".to_string()).unwrap();

        // 立即读取
        let result2 = state.get_string("test.value");
        println!("Second read result: {:?}", result2);

        assert_eq!(
            result2,
            Some("after".to_string()),
            "Should read back the second value"
        );
    }

    #[test]
    fn test_preloaded_config_consistency() {
        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("preloaded_test.toml");

        // 创建测试配置文件
        let config_content = r#"
[database]
host = "original_host"
port = 5432
"#;
        fs::write(&config_path, config_content).unwrap();

        // 创建配置状态实例（这会加载配置文件）
        let state = ConfigState::init_config(&config_path);

        // 检查初始索引
        let initial_index = state.get_current_buffer_index();
        println!("Initial buffer index: {}", initial_index);

        // 读取预加载的配置
        let original_host = state.get_string("database.host");
        let original_port = state.get_i64("database.port");
        println!(
            "Original host: {:?}, port: {:?}",
            original_host, original_port
        );

        // 设置新值
        println!("Setting database.host = 'new_host'");
        state
            .set_string("database.host", "new_host".to_string())
            .unwrap();

        println!("Setting database.port = 3306");
        state.set_i64("database.port", 3306).unwrap();

        // 检查设置后的索引
        let after_set_index = state.get_current_buffer_index();
        println!("After set buffer index: {}", after_set_index);

        // 立即读取
        let new_host = state.get_string("database.host");
        let new_port = state.get_i64("database.port");
        println!("New host: {:?}, port: {:?}", new_host, new_port);

        // 验证一致性
        assert_eq!(
            initial_index, after_set_index,
            "Index should not change after set"
        );
        assert_eq!(
            original_host,
            Some("original_host".to_string()),
            "Should read original host"
        );
        assert_eq!(original_port, Some(5432), "Should read original port");
        assert_eq!(
            new_host,
            Some("new_host".to_string()),
            "Should read new host"
        );
        assert_eq!(new_port, Some(3306), "Should read new port");
    }

    #[test]
    fn test_auto_callback_on_external_change() {
        use std::sync::{Arc, Mutex};
        use std::time::Duration;

        let temp_dir = tempdir().unwrap();
        let config_path = temp_dir.path().join("auto_callback_test.toml");

        // 创建初始配置文件
        let initial_content = r#"
[app]
name = "initial_app"
version = "1.0.0"
"#;
        fs::write(&config_path, initial_content).unwrap();

        // 创建配置状态实例
        let state = ConfigState::init_config(&config_path);

        // 设置回调计数器
        let callback_count = Arc::new(Mutex::new(0));
        let callback_count_clone = callback_count.clone();

        // 添加回调函数（现在会自动触发，无需手动轮询）
        state.add_change_callback(move |_state| {
            let mut count = callback_count_clone.lock().unwrap();
            *count += 1;
            println!("Auto callback triggered! Count: {}", *count);
        });

        // 模拟外部文件修改
        let modified_content = r#"
[app]
name = "externally_modified"
version = "2.0.0"
"#;
        fs::write(&config_path, modified_content).unwrap();

        // 等待文件监听器处理变化并自动触发回调
        std::thread::sleep(Duration::from_millis(500));

        // 验证配置已更新
        assert_eq!(
            state.get_string("app.name"),
            Some("externally_modified".to_string())
        );

        // 验证回调被自动执行
        let final_callback_count = *callback_count.lock().unwrap();
        println!("Final callback count: {}", final_callback_count);

        // 回调应该被自动触发
        assert!(
            final_callback_count >= 1,
            "Callback should have been auto-triggered by external file change"
        );
    }
}