Add duration functions for calculating durations as integers (#257)

lib/src/fnc/duration.rs

@@ -0,0 +1,44 @@
+use crate::err::Error;
+use crate::sql::value::Value;
+
+pub fn days((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.days(),
+		_ => Value::None,
+	})
+}
+
+pub fn hours((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.hours(),
+		_ => Value::None,
+	})
+}
+
+pub fn mins((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.mins(),
+		_ => Value::None,
+	})
+}
+
+pub fn secs((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.secs(),
+		_ => Value::None,
+	})
+}
+
+pub fn weeks((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.weeks(),
+		_ => Value::None,
+	})
+}
+
+pub fn years((duration,): (Value,)) -> Result<Value, Error> {
+	Ok(match duration {
+		Value::Duration(d) => d.years(),
+		_ => Value::None,
+	})
+}

lib/src/fnc/mod.rs

@@ -7,6 +7,7 @@ pub mod array;
 pub mod cast;
 pub mod count;
 pub mod crypto;
+pub mod duration;
 pub mod future;
 pub mod geo;
 pub mod http;
@@ -77,6 +78,13 @@ pub fn synchronous(ctx: &Context<'_>, name: &str, args: Vec<Value>) -> Result<Va
 		"crypto::sha256" => crypto::sha256,
 		"crypto::sha512" => crypto::sha512,
 		//
+		"duration::days" => duration::days,
+		"duration::hours" => duration::hours,
+		"duration::mins" => duration::mins,
+		"duration::secs" => duration::secs,
+		"duration::weeks" => duration::weeks,
+		"duration::years" => duration::years,
+		//
 		"geo::area" => geo::area,
 		"geo::bearing" => geo::bearing,
 		"geo::centroid" => geo::centroid,

lib/src/sql/datetime.rs

@@ -1,4 +1,5 @@
 use crate::sql::common::{take_digits, take_digits_range, take_u32_len};
+use crate::sql::duration::Duration;
 use crate::sql::error::IResult;
 use crate::sql::serde::is_internal_serialization;
 use chrono::{DateTime, FixedOffset, TimeZone, Utc};
@@ -7,9 +8,9 @@ use nom::character::complete::char;
 use nom::combinator::map;
 use nom::sequence::delimited;
 use serde::{Deserialize, Serialize};
-use std::fmt;
 use std::ops::Deref;
 use std::str;
+use std::{fmt, ops};
 
 const SINGLE: char = '\'';
 const DOUBLE: char = '"';
@@ -70,6 +71,16 @@ impl Serialize for Datetime {
 	}
 }
 
+impl ops::Sub<Datetime> for Datetime {
+	type Output = Duration;
+	fn sub(self, other: Datetime) -> Duration {
+		match (self.0 - other.0).to_std() {
+			Ok(d) => Duration::from(d),
+			Err(_) => Duration::default(),
+		}
+	}
+}
+
 pub fn datetime(i: &str) -> IResult<&str, Datetime> {
 	alt((
 		delimited(char(DOUBLE), datetime_raw, char(DOUBLE)),

lib/src/sql/duration.rs

@@ -2,6 +2,7 @@ use crate::sql::common::take_u64;
 use crate::sql::datetime::Datetime;
 use crate::sql::error::IResult;
 use crate::sql::serde::is_internal_serialization;
+use crate::sql::value::Value;
 use chrono::DurationRound;
 use nom::branch::alt;
 use nom::bytes::complete::tag;
@@ -54,6 +55,40 @@ impl Duration {
 	pub fn to_raw(&self) -> String {
 		self.to_string()
 	}
+
+	pub fn secs(&self) -> Value {
+		self.0.as_secs().into()
+	}
+
+	pub fn mins(&self) -> Value {
+		let secs = self.0.as_secs();
+		let mins = secs / SECONDS_PER_MINUTE;
+		mins.into()
+	}
+
+	pub fn hours(&self) -> Value {
+		let secs = self.0.as_secs();
+		let hours = secs / SECONDS_PER_HOUR;
+		hours.into()
+	}
+
+	pub fn days(&self) -> Value {
+		let secs = self.0.as_secs();
+		let days = secs / SECONDS_PER_DAY;
+		days.into()
+	}
+
+	pub fn weeks(&self) -> Value {
+		let secs = self.0.as_secs();
+		let weeks = secs / SECONDS_PER_WEEK;
+		weeks.into()
+	}
+
+	pub fn years(&self) -> Value {
+		let secs = self.0.as_secs();
+		let years = secs / SECONDS_PER_YEAR;
+		years.into()
+	}
 }
 
 impl fmt::Display for Duration {

lib/src/sql/function.rs

@@ -239,6 +239,7 @@ fn function_names(i: &str) -> IResult<&str, &str> {
 		function_array,
 		function_count,
 		function_crypto,
+		function_duration,
 		function_geo,
 		function_http,
 		function_is,
@@ -289,6 +290,17 @@ fn function_crypto(i: &str) -> IResult<&str, &str> {
 	))(i)
 }
 
+fn function_duration(i: &str) -> IResult<&str, &str> {
+	alt((
+		tag("duration::days"),
+		tag("duration::hours"),
+		tag("duration::mins"),
+		tag("duration::secs"),
+		tag("duration::weeks"),
+		tag("duration::years"),
+	))(i)
+}
+
 fn function_geo(i: &str) -> IResult<&str, &str> {
 	alt((
 		tag("geo::area"),

lib/src/sql/value/value.rs

@@ -1199,6 +1199,7 @@ impl ops::Sub for Value {
 	fn sub(self, other: Self) -> Self {
 		match (self, other) {
 			(Value::Number(v), Value::Number(w)) => Value::Number(v - w),
+			(Value::Datetime(v), Value::Datetime(w)) => Value::Duration(v - w),
 			(Value::Datetime(v), Value::Duration(w)) => Value::Datetime(w - v),
 			(Value::Duration(v), Value::Datetime(w)) => Value::Datetime(v - w),
 			(Value::Duration(v), Value::Duration(w)) => Value::Duration(v - w),