atlas-common 0.1.1

//! Date and time handling for C2PA manifests

use crate::error::{Error, Result};
use serde::{Deserialize, Serialize};
use time::OffsetDateTime;

/// Wrapper for OffsetDateTime with serde support and validation
///
/// Ensures timestamps are valid and in the correct format for C2PA manifests.
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct DateTimeWrapper(#[serde(with = "time::serde::rfc3339")] pub OffsetDateTime);

impl DateTimeWrapper {
    /// Create new with current UTC time
    ///
    /// # Example
    ///
    /// ```rust
    /// use atlas_common::c2pa::DateTimeWrapper;
    ///
    /// let now = DateTimeWrapper::now_utc();
    /// println!("Current time: {}", now.to_rfc3339());
    /// ```
    pub fn now_utc() -> Self {
        Self(OffsetDateTime::now_utc())
    }

    /// Validate that the datetime is reasonable
    ///
    /// Checks that:
    /// - The date is after January 1, 1970
    /// - The date is not in the future
    ///
    /// # Errors
    ///
    /// Returns an error if validation fails.
    pub fn validate(&self) -> Result<()> {
        if self.0.year() < 1970 {
            return Err(Error::Time(
                "Datetime must be after January 1, 1970".to_string(),
            ));
        }

        let now = OffsetDateTime::now_utc();
        if self.0 > now {
            return Err(Error::Time("Datetime cannot be in the future".to_string()));
        }

        Ok(())
    }

    /// Get as RFC3339 string
    ///
    /// Returns the datetime formatted according to RFC3339 standard.
    pub fn to_rfc3339(&self) -> String {
        self.0
            .format(&time::format_description::well_known::Rfc3339)
            .unwrap_or_else(|_| self.0.to_string())
    }
}

impl Default for DateTimeWrapper {
    fn default() -> Self {
        Self::now_utc()
    }
}

impl std::fmt::Display for DateTimeWrapper {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}", self.to_rfc3339())
    }
}