Move the context objects to a dedicated module

src/context.rs

@@ -0,0 +1,50 @@
+use std::num::NonZeroU64;
+
+pub struct DataContext {
+	ctx: Vec<String>,
+}
+
+impl DataContext {
+	pub(crate) fn get_ctx_elems(&self) -> &[String] {
+		self.ctx.as_ref()
+	}
+}
+
+impl<const N: usize> From<[&str; N]> for DataContext {
+	fn from(ctx: [&str; N]) -> Self {
+		Self {
+			ctx: ctx.iter().map(|s| s.to_string()).collect(),
+		}
+	}
+}
+
+pub struct KeyContext {
+	pub(crate) ctx: Vec<String>,
+	pub(crate) periodicity: Option<u64>,
+}
+
+impl KeyContext {
+	pub fn set_static(&mut self) {
+		self.periodicity = None;
+	}
+
+	pub fn set_periodicity(&mut self, periodicity: NonZeroU64) {
+		self.periodicity = Some(periodicity.get());
+	}
+
+	pub(crate) fn get_ctx_elems(&self, time_period: Option<u64>) -> Vec<Vec<u8>> {
+		let mut ret: Vec<Vec<u8>> = self.ctx.iter().map(|s| s.as_bytes().to_vec()).collect();
+		if let Some(tp) = time_period {
+			ret.push(tp.to_le_bytes().to_vec());
+		}
+		ret
+	}
+
+	pub(crate) fn get_time_period(&self, timestamp: u64) -> Option<u64> {
+		self.periodicity.map(|p| timestamp / p)
+	}
+
+	pub(crate) fn is_periodic(&self) -> bool {
+		self.periodicity.is_some()
+	}
+}