// Charter标准库 - 时间处理模块
// 提供时间戳、日期时间、时区转换等功能

module std::time;

// 时间戳结构
struct Timestamp {
    seconds: u64,      // Unix时间戳（秒）
    nanos: u32,        // 纳秒部分
}

impl Timestamp {
    // 获取当前时间戳
    public fun now() -> Timestamp {
        let seconds = native_timestamp_seconds();
        let nanos = native_timestamp_nanos();
        Timestamp { seconds, nanos }
    }
    
    // 从秒创建时间戳
    public fun from_seconds(seconds: u64) -> Timestamp {
        Timestamp { seconds, nanos: 0 }
    }
    
    // 转换为秒
    public fun as_seconds(&self) -> u64 {
        self.seconds
    }
    
    // 转换为毫秒
    public fun as_millis(&self) -> u64 {
        self.seconds * 1000 + (self.nanos / 1_000_000) as u64
    }
    
    // 添加秒数
    public fun add_seconds(&mut self, seconds: u64) {
        self.seconds += seconds;
    }
    
    // 添加天数
    public fun add_days(&mut self, days: u64) {
        self.seconds += days * 86400;
    }
    
    // 比较时间戳
    public fun is_before(&self, other: &Timestamp) -> bool {
        if self.seconds < other.seconds {
            return true;
        }
        if self.seconds == other.seconds && self.nanos < other.nanos {
            return true;
        }
        false
    }
    
    // 计算时间差（秒）
    public fun diff_seconds(&self, other: &Timestamp) -> u64 {
        if self.seconds >= other.seconds {
            self.seconds - other.seconds
        } else {
            other.seconds - self.seconds
        }
    }
}

// 日期时间结构
struct DateTime {
    year: u32,
    month: u8,    // 1-12
    day: u8,      // 1-31
    hour: u8,     // 0-23
    minute: u8,   // 0-59
    second: u8,   // 0-59
}

impl DateTime {
    // 创建日期时间
    public fun new(year: u32, month: u8, day: u8, hour: u8, minute: u8, second: u8) -> DateTime {
        DateTime { year, month, day, hour, minute, second }
    }
    
    // 转换为时间戳
    public fun to_timestamp(&self) -> Timestamp {
        let seconds = datetime_to_unix(self.year, self.month, self.day, self.hour, self.minute, self.second);
        Timestamp::from_seconds(seconds)
    }
    
    // 从时间戳创建
    public fun from_timestamp(ts: &Timestamp) -> DateTime {
        unix_to_datetime(ts.seconds)
    }
}

// Native函数声明
native fun native_timestamp_seconds() -> u64;
native fun native_timestamp_nanos() -> u32;
native fun datetime_to_unix(year: u32, month: u8, day: u8, hour: u8, minute: u8, second: u8) -> u64;
native fun unix_to_datetime(seconds: u64) -> DateTime;