Separates date_utc and datetime_utc

8 files changed, 543 insertions, 196 deletions

diff --git a/backend/core/src/models/account.rs b/backend/core/src/models/account.rs
index fcd5270..2df43e1 100644
--- a/backend/core/src/models/account.rs
+++ b/backend/core/src/models/account.rs
@@ -1,7 +1,7 @@
 use diesel::prelude::*;
 use serde::{Deserialize, Serialize};
 
-use crate::models::date_time_utc::DateTimeUtc;
+use crate::models::datetime_utc::DatetimeUtc;
 
 #[derive(
     Insertable, Queryable, Identifiable, Selectable, Debug, PartialEq, Clone, Serialize, Deserialize,
@@ -11,5 +11,5 @@ pub struct Account {
     pub id: i32,
     pub name: String,
     pub opening_balance: i32,
-    pub opening_date: DateTimeUtc,
+    pub opening_date: DatetimeUtc,
 }
diff --git a/backend/core/src/models/budget.rs b/backend/core/src/models/budget.rs
index 08a1c72..45ab534 100644
--- a/backend/core/src/models/budget.rs
+++ b/backend/core/src/models/budget.rs
@@ -19,9 +19,7 @@ impl From<&BudgetUpdate> for Budget {
 
 #[cfg(test)]
 mod test {
-    use chrono::Utc;
-
-    use crate::models::date_time_utc::DateTimeUtc;
+    use crate::{models::date_utc::DateUtc, traits::nowlike::Nowlike};
 
     use super::*;
 
@@ -32,7 +30,7 @@ mod test {
         let budget_update = BudgetUpdate {
             id: 0,
             category_id: 1,
-            date: DateTimeUtc::new(&Utc::now()),
+            date: DateUtc::now(),
             new_budget: quantity,
             new_period: period,
         };
diff --git a/backend/core/src/models/budget_update.rs b/backend/core/src/models/budget_update.rs
index 3500d8e..c7221b1 100644
--- a/backend/core/src/models/budget_update.rs
+++ b/backend/core/src/models/budget_update.rs
@@ -2,17 +2,15 @@ use derive_builder::Builder;
 use diesel::prelude::*;
 use serde::Serialize;
 
-use crate::models::category::Category;
+use crate::models::{category::Category, date_utc::DateUtc};
 
-use super::date_time_utc::DateTimeUtc;
-
-#[derive(Builder, Clone, Serialize, Queryable, Identifiable, Selectable, Associations, Debug, PartialEq, Insertable)]
+#[derive(Builder, Clone, Serialize, Queryable, Identifiable, Selectable, Associations, Debug, PartialEq, Eq, Insertable)]
 #[diesel(table_name = crate::schema::budget_updates)]
 #[diesel(belongs_to(Category))]
 pub struct BudgetUpdate {
     pub id: i32,
     pub category_id: i32,
-    pub date: DateTimeUtc,
+    pub date: DateUtc,
     pub new_budget: i32,
     pub new_period: i32,
 }
diff --git a/backend/core/src/models/date_time_utc.rs b/backend/core/src/models/date_time_utc.rs
deleted file mode 100644
index d59d8f4..0000000
--- a/backend/core/src/models/date_time_utc.rs
+++ /dev/null
@@ -1,182 +0,0 @@
-use anyhow::{Error, Result};
-use chrono::{DateTime, Datelike, Utc};
-use diesel::{
-    backend::Backend,
-    deserialize::{self, FromSql, FromSqlRow},
-    expression::AsExpression,
-    serialize::{self, ToSql},
-    sql_types::Text,
-    sqlite::Sqlite,
-};
-use serde::{Deserialize, Serialize};
-
-#[derive(
-    Eq,
-    PartialEq,
-    Ord,
-    PartialOrd,
-    Serialize,
-    Deserialize,
-    Clone,
-    Debug,
-    AsExpression,
-    FromSqlRow,
-)]
-#[diesel(sql_type=Text)]
-pub struct DateTimeUtc {
-    chrono_datetime_utc: DateTime<Utc>,
-}
-
-impl DateTimeUtc {
-    pub fn day_diff(&self, other: &DateTimeUtc) -> u32 {
-        self.chrono_datetime_utc
-            .num_days_from_ce()
-            .abs_diff(other.chrono_datetime_utc.num_days_from_ce())
-    }
-
-    pub fn new(chrono_datetime_utc: &DateTime<Utc>) -> Self {
-        Self {
-            chrono_datetime_utc: chrono_datetime_utc.clone(),
-        }
-    }
-
-    pub fn now() -> Self {
-        Self::new(&Utc::now())
-    }
-
-    /// Constructs DateTimeUtc from a day string, YYYY-MM-DD, in UTC
-    /// Example: "2024-10-24" -> Midnight 24 Oct 2024 UTC
-    pub fn from_day_str(day_str: &str) -> Result<Self> {
-        if !Self::is_day_str(day_str) {
-            Err(Error::msg(format!("{} is not a day string in YYYY-MM-DD format", day_str)))
-        } else {
-            let mut date_str = String::from(day_str);
-            date_str.push_str("T00:00:00.000Z");
-            Ok(Self::from_date_str(&date_str)?)
-        }
-    }
-
-    /// Constructs DateTimeUtc from a date string in ISO format, in UTC
-    /// Example: "2024-10-24T10:30:00.000" -> 10.30am 24 Oct 2024 UTC
-    pub fn from_date_str(date_time_utc: &str) -> Result<Self> {
-        let chrono_datetime_utc = date_time_utc.parse::<DateTime<Utc>>()?;
-        Ok(Self {
-            chrono_datetime_utc,
-        })
-    }
-
-    /// Converts to a day string, YYYY-MM-DD, in UTC
-    /// Example: 10.30am 24 Oct 2024 UTC -> "2024-10-24"
-    pub fn to_day_str(&self) -> String {
-        let date_str = self.to_date_str();
-        let day_str = date_str
-            .split_at_checked(10)
-            .unwrap()
-            .0;
-        String::from(day_str)
-    }
-
-    /// Converts to a date string in ISO format, in UTC
-    /// Example: 10.30am 24 Oct 2024 UTC -> "2024-10-24T10:30:00.000Z"
-    pub fn to_date_str(&self) -> String {
-        self.chrono_datetime_utc.to_rfc3339()
-    }
-
-
-    fn is_day_str(str: &str) -> bool {
-        if str.len() != 10 {
-            return false;
-        }
-        for (ix, ch) in str.chars().enumerate() {
-            if ix == 4 || ix == 7 {
-                if ch != '-' {
-                    return false;
-                }
-            } else {
-                if ch < '0' || ch > '9' {
-                    return false;
-                }
-            }
-        }
-        return true;
-    }
-}
-
-impl ToSql<Text, Sqlite> for DateTimeUtc {
-    fn to_sql<'b>(
-        &'b self,
-        out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
-    ) -> serialize::Result {
-        out.set_value(self.to_date_str());
-        Ok(serialize::IsNull::No)
-    }
-}
-
-impl FromSql<Text, Sqlite> for DateTimeUtc {
-    fn from_sql(bytes: <Sqlite as Backend>::RawValue<'_>) -> deserialize::Result<DateTimeUtc> {
-        let str = <String as FromSql<Text, Sqlite>>::from_sql(bytes)?;
-        Ok(Self::from_date_str(&str)?)
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use chrono::TimeZone;
-
-    use super::*;
-
-    #[test]
-    fn given_midnight_when_day_diff_next_midnight_less_1s_then_return_0() {
-        let start = DateTimeUtc::new(&Utc.with_ymd_and_hms(2000, 1, 1, 0, 0, 0).unwrap().to_utc());
-        let end = DateTimeUtc::new(
-            &Utc.with_ymd_and_hms(2000, 1, 1, 23, 59, 59)
-                .unwrap()
-                .to_utc(),
-        );
-
-        let day_diff = start.day_diff(&end);
-        let neg_day_diff = end.day_diff(&start);
-
-        assert_eq!(day_diff, 0);
-        assert_eq!(day_diff, neg_day_diff);
-    }
-
-    #[test]
-    fn given_midnight_when_day_diff_next_midnight_then_return_1() {
-        let start = DateTimeUtc::new(&Utc.with_ymd_and_hms(2000, 1, 1, 0, 0, 0).unwrap().to_utc());
-        let end = DateTimeUtc::new(&Utc.with_ymd_and_hms(2000, 1, 2, 0, 0, 0).unwrap().to_utc());
-
-        let day_diff = start.day_diff(&end);
-        let neg_day_diff = end.day_diff(&start);
-
-        assert_eq!(day_diff, 1);
-        assert_eq!(day_diff, neg_day_diff);
-    }
-
-    #[test]
-    fn given_midnight_less_1s_when_day_diff_midnight_then_return_1() {
-        let start = DateTimeUtc::new(
-            &Utc.with_ymd_and_hms(2000, 1, 1, 23, 59, 59)
-                .unwrap()
-                .to_utc(),
-        );
-        let end = DateTimeUtc::new(&Utc.with_ymd_and_hms(2000, 1, 2, 0, 0, 0).unwrap().to_utc());
-
-        let day_diff = start.day_diff(&end);
-        let neg_day_diff = end.day_diff(&start);
-
-        assert_eq!(day_diff, 1);
-        assert_eq!(day_diff, neg_day_diff);
-    }
-
-    #[test]
-    fn given_23_nov_1970_when_to_day_str_then_return_iso_day_str() {
-        let date_time_utc = DateTimeUtc::new(
-            &Utc.with_ymd_and_hms(1970, 11, 23, 0, 0, 0)
-                .unwrap()
-                .to_utc(),
-        );
-
-        assert_eq!(date_time_utc.to_day_str(), "1970-11-23");
-    }
-}
diff --git a/backend/core/src/models/date_utc.rs b/backend/core/src/models/date_utc.rs
new file mode 100644
index 0000000..55d9e3f
--- /dev/null
+++ b/backend/core/src/models/date_utc.rs
@@ -0,0 +1,309 @@
+use std::{borrow::Borrow, fmt, str::FromStr};
+
+use anyhow::{Context, Error, Result};
+use chrono::{DateTime, Datelike, NaiveDate, NaiveTime, Utc};
+use diesel::{
+    backend::Backend,
+    deserialize::{self, FromSql, FromSqlRow},
+    expression::AsExpression,
+    serialize::{self, ToSql},
+    sql_types::Text,
+    sqlite::Sqlite,
+};
+use serde::{Deserialize, Serialize};
+
+use crate::traits::{dateable::Dateable, nowlike::Nowlike};
+
+use super::datetime_utc::DatetimeUtc;
+
+#[derive(
+    Eq,
+    PartialEq,
+    Ord,
+    PartialOrd,
+    Serialize,
+    Deserialize,
+    Clone,
+    Debug,
+    AsExpression,
+    FromSqlRow,
+)]
+#[diesel(sql_type=Text)]
+pub struct DateUtc {
+    chrono_datetime_utc: DateTime<Utc>,
+}
+
+impl DateUtc {
+    pub fn from_ymd(year: i32, month: u32, day: u32) -> Result<Self> {
+        Ok(Self {
+            chrono_datetime_utc: NaiveDate::from_ymd_opt(year, month, day)
+                .with_context(|| format!("failed to construct date from ymd {:04}-{:02}-{:02}", year, month, day))?
+                .and_hms_opt(0, 0, 0).unwrap()
+                .and_utc()
+        })
+    }
+
+    pub fn with_hms(&mut self, hour: u32, min: u32, sec: u32) -> Result<DatetimeUtc> {
+        DatetimeUtc::from_ymd_and_hms(
+            self.year(), self.month(), self.day(), hour, min, sec,
+        )
+    }
+
+    pub fn day_diff(&self, other: &DateUtc) -> u32 {
+        self.chrono_datetime_utc
+            .num_days_from_ce()
+            .abs_diff(other.chrono_datetime_utc.num_days_from_ce())
+    }
+
+    fn is_day_str(str: &str) -> bool {
+        if str.len() != 10 {
+            return false;
+        }
+        for (ix, ch) in str.chars().enumerate() {
+            if ix == 4 || ix == 7 {
+                if ch != '-' {
+                    return false;
+                }
+            } else {
+                if ch < '0' || ch > '9' {
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+}
+
+impl Nowlike for DateUtc {
+    fn now() -> Self {
+        let now = Utc::now();
+        Self::from_ymd(
+            now.year(),
+            now.month(),
+            now.day(),
+        ).unwrap()
+    }
+}
+
+impl Dateable for DateUtc {
+    fn year(&self) -> i32 {
+        self.chrono_datetime_utc.year()
+    }
+
+    fn month(&self) -> u32 {
+        self.chrono_datetime_utc.month()
+    }
+
+    fn day(&self) -> u32 {
+        self.chrono_datetime_utc.day()
+    }
+}
+
+impl From<DatetimeUtc> for DateUtc {
+    fn from(datetime_utc: DatetimeUtc) -> Self {
+        Self {
+            chrono_datetime_utc: datetime_utc
+                .borrow()
+                .to_string()
+                .parse::<DateTime<Utc>>().unwrap()
+                .with_time(NaiveTime::from_hms_opt(0, 0, 0).unwrap()).unwrap(),
+        }
+    }
+}
+
+impl<T> From<T> for DateUtc where T: Borrow<DateTime<Utc>> {
+    fn from(chrono_datetime_utc: T) -> Self {
+        Self {
+            chrono_datetime_utc: chrono_datetime_utc
+                .borrow()
+                .with_time(NaiveTime::from_hms_opt(0, 0, 0).unwrap()).unwrap(),
+        }
+    }
+}
+
+impl fmt::Display for DateUtc {
+    /// Converts to a day string, YYYY-MM-DD, in UTC
+    /// Example: 10.30am 24 Oct 2024 UTC -> "2024-10-24"
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        let date_str = self.chrono_datetime_utc.to_rfc3339();
+        let day_str = date_str
+            .split_at_checked(10)
+            .unwrap()
+            .0;
+        write!(f, "{}", day_str)
+    }
+}
+
+impl FromStr for DateUtc {
+    type Err = anyhow::Error;
+
+    /// Constructs DatetimeUtc from a day string, YYYY-MM-DD, in UTC
+    /// Example: "2024-10-24" -> Midnight 24 Oct 2024 UTC
+    fn from_str(date_str: &str) -> Result<Self> {
+        if !Self::is_day_str(&date_str) {
+            Err(Error::msg(format!("{} is not a day string in YYYY-MM-DD format", date_str)))
+        } else {
+            let mut datetime_str = String::from(date_str);
+            datetime_str.push_str("T00:00:00.000Z");
+            Ok(Self {
+                chrono_datetime_utc: datetime_str.parse()?,
+            })
+        }
+    }
+}
+
+impl ToSql<Text, Sqlite> for DateUtc {
+    fn to_sql<'b>(
+        &'b self,
+        out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
+    ) -> serialize::Result {
+        out.set_value(self.to_string());
+        Ok(serialize::IsNull::No)
+    }
+}
+
+impl FromSql<Text, Sqlite> for DateUtc {
+    fn from_sql(bytes: <Sqlite as Backend>::RawValue<'_>) -> deserialize::Result<DateUtc> {
+        let str = <String as FromSql<Text, Sqlite>>::from_sql(bytes)?;
+        Ok(str.parse()?)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::traits::timeable::Timeable;
+
+    use super::*;
+
+    #[test]
+    fn when_from_ymd_then_ymd_are_as_expected() {
+        let date_utc = DateUtc::from_ymd(1970, 11, 23);
+
+        assert!(date_utc.is_ok());
+        let date_utc = date_utc.unwrap();
+        assert_eq!(date_utc.year(), 1970);
+        assert_eq!(date_utc.month(), 11);
+        assert_eq!(date_utc.day(), 23);
+    }
+
+    #[test]
+    fn when_from_ymd_then_to_string_as_expected() {
+        let date_utc = DateUtc::from_ymd(1970, 11, 23);
+
+        assert!(date_utc.is_ok());
+        assert_eq!(date_utc.unwrap().to_string(), "1970-11-23");
+    }
+
+    #[test]
+    fn when_from_invalid_ymd_then_err() {
+        let date_utc_1 = DateUtc::from_ymd(1970, 0, 23);
+        let date_utc_2 = DateUtc::from_ymd(1970, 13, 23);
+        let date_utc_3 = DateUtc::from_ymd(1970, 11, 0);
+        let date_utc_4 = DateUtc::from_ymd(1970, 11, 31);
+        let date_utc_5 = DateUtc::from_ymd(1971, 2, 29);
+
+        assert!(date_utc_1.is_err());
+        assert_eq!(date_utc_1.unwrap_err().to_string(), "failed to construct date from ymd 1970-00-23");
+        assert!(date_utc_2.is_err());
+        assert_eq!(date_utc_2.unwrap_err().to_string(), "failed to construct date from ymd 1970-13-23");
+        assert!(date_utc_3.is_err());
+        assert_eq!(date_utc_3.unwrap_err().to_string(), "failed to construct date from ymd 1970-11-00");
+        assert!(date_utc_4.is_err());
+        assert_eq!(date_utc_4.unwrap_err().to_string(), "failed to construct date from ymd 1970-11-31");
+        assert!(date_utc_5.is_err());
+        assert_eq!(date_utc_5.unwrap_err().to_string(), "failed to construct date from ymd 1971-02-29");
+    }
+
+    #[test]
+    fn when_from_string_then_ymd_are_as_expected() {
+        let date_utc: Result<DateUtc> = "1970-11-23".parse();
+
+        assert!(date_utc.is_ok());
+        let date_utc = date_utc.unwrap();
+        assert_eq!(date_utc.year(), 1970);
+        assert_eq!(date_utc.month(), 11);
+        assert_eq!(date_utc.day(), 23);
+    }
+
+    #[test]
+    fn when_from_string_then_to_string_as_expected() {
+        let date_utc: Result<DateUtc> = "1970-11-23".parse();
+
+        assert!(date_utc.is_ok());
+        assert_eq!(date_utc.unwrap().to_string(), "1970-11-23");
+    }
+
+    #[test]
+    fn when_from_invalid_string_then_err() {
+        let date_utc_1: Result<DateUtc> = "1970-00-23".parse();
+        let date_utc_2: Result<DateUtc> = "1970-13-23".parse();
+        let date_utc_3: Result<DateUtc> = "1970-11-0".parse();
+        let date_utc_4: Result<DateUtc> = "1970-11-31".parse();
+        let date_utc_5: Result<DateUtc> = "1971-02-29".parse();
+
+        assert!(date_utc_1.is_err());
+        assert!(date_utc_2.is_err());
+        assert!(date_utc_3.is_err());
+        assert!(date_utc_4.is_err());
+        assert!(date_utc_5.is_err());
+    }
+
+    #[test]
+    fn with_with_hms_then_ymd_hms_are_as_expected() {
+        let datetime_utc = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(12, 55, 16);
+
+        assert!(datetime_utc.is_ok());
+        let datetime_utc = datetime_utc.unwrap();
+        assert_eq!(datetime_utc.year(), 1970);
+        assert_eq!(datetime_utc.month(), 11);
+        assert_eq!(datetime_utc.day(), 23);
+        assert_eq!(datetime_utc.hour(), 12);
+        assert_eq!(datetime_utc.minute(), 55);
+        assert_eq!(datetime_utc.second(), 16);
+    }
+
+    #[test]
+    fn when_with_invalid_hms_then_err() {
+        let datetime_utc_1 = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(25, 0, 0);
+        let datetime_utc_2 = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(0, 61, 0);
+        let datetime_utc_3 = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(0, 0, 61);
+
+        assert!(datetime_utc_1.is_err());
+        assert!(datetime_utc_2.is_err());
+        assert!(datetime_utc_3.is_err());
+    }
+
+    #[test]
+    fn when_from_datetime_utc_at_different_times_on_same_day_then_eq() {
+        let datetime_utc1 = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(0, 0, 0).unwrap();
+        let datetime_utc2 = DateUtc::from_ymd(1970, 11, 23).unwrap().with_hms(23, 59, 59).unwrap();
+        let date_utc1 = DateUtc::from(datetime_utc1);
+        let date_utc2 = DateUtc::from(datetime_utc2);
+
+        assert_eq!(date_utc1, date_utc2);
+    }
+
+    #[test]
+    fn given_today_when_day_diff_today_then_return_0() {
+        let start = DateUtc::from_ymd(2000, 1, 1).unwrap();
+        let end = DateUtc::from_ymd(2000, 1, 1).unwrap();
+
+        let day_diff = start.day_diff(&end);
+        let neg_day_diff = end.day_diff(&start);
+
+        assert_eq!(day_diff, 0);
+        assert_eq!(day_diff, neg_day_diff);
+    }
+
+    #[test]
+    fn given_today_when_day_diff_tomorrow_then_return_1() {
+        let start = DateUtc::from_ymd(2000, 1, 1).unwrap();
+        let end = DateUtc::from_ymd(2000, 1, 2).unwrap();
+
+        let day_diff = start.day_diff(&end);
+        let neg_day_diff = end.day_diff(&start);
+
+        assert_eq!(day_diff, 1);
+        assert_eq!(day_diff, neg_day_diff);
+    }
+}
diff --git a/backend/core/src/models/datetime_utc.rs b/backend/core/src/models/datetime_utc.rs
new file mode 100644
index 0000000..98d1d6c
--- /dev/null
+++ b/backend/core/src/models/datetime_utc.rs
@@ -0,0 +1,223 @@
+use std::{fmt::Display, str::FromStr};
+
+use anyhow::{Context, Result};
+use chrono::{DateTime, Datelike as ChronoDatelike, NaiveDate, Timelike as ChronoTimelike, Utc};
+use diesel::{
+    backend::Backend,
+    deserialize::{self, FromSql, FromSqlRow},
+    expression::AsExpression,
+    serialize::{self, ToSql},
+    sql_types::Text,
+    sqlite::Sqlite,
+};
+use serde::{Deserialize, Serialize};
+
+use crate::traits::{dateable::Dateable, nowlike::Nowlike, timeable::Timeable};
+
+#[derive(
+    PartialEq,
+    Eq,
+    PartialOrd,
+    Ord,
+    Serialize,
+    Deserialize,
+    Clone,
+    Debug,
+    AsExpression,
+    FromSqlRow,
+)]
+#[diesel(sql_type=Text)]
+pub struct DatetimeUtc {
+    chrono_datetime_utc: DateTime<Utc>,
+}
+
+impl DatetimeUtc {
+    pub fn from_ymd_and_hms(year: i32, month: u32, day: u32, hour: u32, min: u32, sec: u32) -> Result<Self> {
+        Ok(Self { chrono_datetime_utc: NaiveDate
+            ::from_ymd_opt(year, month, day)
+            .with_context(|| format!("failed to construct datetime from ymd {:04}-{:02}-{:02}", year, month, day))?
+            .and_hms_opt(hour, min, sec)
+            .with_context(|| format!("failed to construct datetime from hms {:02}:{:02}:{:02}", hour, min, sec))?
+            .and_utc()
+        })
+    }
+}
+
+impl FromStr for DatetimeUtc {
+    type Err = anyhow::Error;
+
+    /// Constructs DatetimeUtc from a date string in ISO format, in UTC
+    /// Example: "2024-10-24T10:30:00.000" -> 10.30am 24 Oct 2024 UTC
+    fn from_str(datetime_str: &str) -> Result<Self> {
+        let chrono_datetime_utc = datetime_str.parse::<DateTime<Utc>>()?;
+        Ok(Self {
+            chrono_datetime_utc,
+        })
+    }
+}
+
+impl Display for DatetimeUtc {
+    /// Converts to a date string in ISO format, in UTC
+    /// Example: 10.30am 24 Oct 2024 UTC -> "2024-10-24T10:30:00.000Z"
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", self.chrono_datetime_utc.to_rfc3339_opts(chrono::SecondsFormat::Millis, true))
+    }
+}
+
+impl Nowlike for DatetimeUtc {
+    fn now() -> Self {
+        let now = Utc::now();
+        Self::from_ymd_and_hms(
+            now.year(),
+            now.month(),
+            now.day(),
+            now.hour(),
+            now.minute(),
+            now.second(),
+        ).unwrap()
+    }
+}
+
+impl Dateable for DatetimeUtc {
+    fn year(&self) -> i32 {
+        self.chrono_datetime_utc.year()
+    }
+
+    fn month(&self) -> u32 {
+        self.chrono_datetime_utc.month()
+    }
+
+    fn day(&self) -> u32 {
+        self.chrono_datetime_utc.day()
+    }
+}
+
+impl Timeable for DatetimeUtc {
+    fn hour(&self) -> u32 {
+        self.chrono_datetime_utc.hour()
+    }
+
+    fn minute(&self) -> u32 {
+        self.chrono_datetime_utc.minute()
+    }
+
+    fn second(&self) -> u32 {
+        self.chrono_datetime_utc.second()
+    }
+}
+
+impl ToSql<Text, Sqlite> for DatetimeUtc {
+    fn to_sql<'b>(
+        &'b self,
+        out: &mut diesel::serialize::Output<'b, '_, Sqlite>,
+    ) -> serialize::Result {
+        out.set_value::<String>(self.to_string());
+        Ok(serialize::IsNull::No)
+    }
+}
+
+impl FromSql<Text, Sqlite> for DatetimeUtc {
+    fn from_sql(bytes: <Sqlite as Backend>::RawValue<'_>) -> deserialize::Result<DatetimeUtc> {
+        let str = <String as FromSql<Text, Sqlite>>::from_sql(bytes)?;
+        Ok(str.parse()?)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn when_from_ymd_and_hms_then_ymd_and_hms_are_as_expected() {
+        let datetime_utc = DatetimeUtc::from_ymd_and_hms(1970, 11, 23, 12, 55, 16);
+
+        assert!(datetime_utc.is_ok());
+        let date_utc = datetime_utc.unwrap();
+        assert_eq!(date_utc.year(), 1970);
+        assert_eq!(date_utc.month(), 11);
+        assert_eq!(date_utc.day(), 23);
+        assert_eq!(date_utc.hour(), 12);
+        assert_eq!(date_utc.minute(), 55);
+        assert_eq!(date_utc.second(), 16);
+    }
+
+    #[test]
+    fn when_from_ymd_and_hms_then_to_string_as_expected() {
+        let date_utc = DatetimeUtc::from_ymd_and_hms(1970, 11, 23, 12, 55, 16);
+
+        assert!(date_utc.is_ok());
+        assert_eq!(date_utc.unwrap().to_string(), "1970-11-23T12:55:16.000Z")
+    }
+
+    #[test]
+    fn when_with_invalid_ymd_and_hms_then_err() {
+        let datetime_utc_1 = DatetimeUtc::from_ymd_and_hms(1970, 0, 23, 12, 55, 16);
+        let datetime_utc_2 = DatetimeUtc::from_ymd_and_hms(1970, 13, 23, 12, 55, 16);
+        let datetime_utc_3 = DatetimeUtc::from_ymd_and_hms(1970, 11, 0, 12, 55, 16);
+        let datetime_utc_4 = DatetimeUtc::from_ymd_and_hms(1970, 11, 31, 12, 55, 16);
+        let datetime_utc_5 = DatetimeUtc::from_ymd_and_hms(1971, 2, 29, 12, 55, 16);
+        let datetime_utc_6 = DatetimeUtc::from_ymd_and_hms(1970, 11, 23, 25, 0, 0);
+        let datetime_utc_7 = DatetimeUtc::from_ymd_and_hms(1970, 11, 23, 0, 61, 0);
+        let datetime_utc_8 = DatetimeUtc::from_ymd_and_hms(1970, 11, 23, 0, 0, 61);
+
+        assert!(datetime_utc_1.is_err());
+        assert_eq!(datetime_utc_1.unwrap_err().to_string(), "failed to construct datetime from ymd 1970-00-23");
+        assert!(datetime_utc_2.is_err());
+        assert_eq!(datetime_utc_2.unwrap_err().to_string(), "failed to construct datetime from ymd 1970-13-23");
+        assert!(datetime_utc_3.is_err());
+        assert_eq!(datetime_utc_3.unwrap_err().to_string(), "failed to construct datetime from ymd 1970-11-00");
+        assert!(datetime_utc_4.is_err());
+        assert_eq!(datetime_utc_4.unwrap_err().to_string(), "failed to construct datetime from ymd 1970-11-31");
+        assert!(datetime_utc_5.is_err());
+        assert_eq!(datetime_utc_5.unwrap_err().to_string(), "failed to construct datetime from ymd 1971-02-29");
+        assert!(datetime_utc_6.is_err());
+        assert_eq!(datetime_utc_6.unwrap_err().to_string(), "failed to construct datetime from hms 25:00:00");
+        assert!(datetime_utc_7.is_err());
+        assert_eq!(datetime_utc_7.unwrap_err().to_string(), "failed to construct datetime from hms 00:61:00");
+        assert!(datetime_utc_8.is_err());
+        assert_eq!(datetime_utc_8.unwrap_err().to_string(), "failed to construct datetime from hms 00:00:61");
+    }
+
+    #[test]
+    fn when_from_string_then_ymd_and_hms_are_as_expected() {
+        let date_utc: Result<DatetimeUtc> = "1970-11-23T12:55:16.000Z".parse();
+
+        assert!(date_utc.is_ok());
+        let datetime_utc = date_utc.unwrap();
+        assert_eq!(datetime_utc.year(), 1970);
+        assert_eq!(datetime_utc.month(), 11);
+        assert_eq!(datetime_utc.day(), 23);
+        assert_eq!(datetime_utc.hour(), 12);
+        assert_eq!(datetime_utc.minute(), 55);
+        assert_eq!(datetime_utc.second(), 16);
+    }
+
+    #[test]
+    fn when_from_string_then_to_string_as_expected() {
+        let datetime_utc: Result<DatetimeUtc> = "1970-11-23T12:55:16.000Z".parse();
+
+        assert!(datetime_utc.is_ok());
+        assert_eq!(datetime_utc.unwrap().to_string(), "1970-11-23T12:55:16.000Z")
+    }
+
+    #[test]
+    fn when_from_invalid_string_then_err() {
+        let datetime_utc_1: Result<DatetimeUtc> = "1970-00-23T00:00:00.000Z".parse();
+        let datetime_utc_2: Result<DatetimeUtc> = "1970-13-23T00:00:00.000Z".parse();
+        let datetime_utc_3: Result<DatetimeUtc> = "1970-11-0T00:00:00.000Z".parse();
+        let datetime_utc_4: Result<DatetimeUtc> = "1970-11-31T00:00:00.000Z".parse();
+        let datetime_utc_5: Result<DatetimeUtc> = "1971-02-29T00:00:00.000Z".parse();
+        let datetime_utc_6: Result<DatetimeUtc> = "1970-11-23T25:00:00.000Z".parse();
+        let datetime_utc_7: Result<DatetimeUtc> = "1970-11-23T00:61:00.000Z".parse();
+        let datetime_utc_8: Result<DatetimeUtc> = "1970-11-23T00:00:61.000Z".parse();
+
+        assert!(datetime_utc_1.is_err());
+        assert!(datetime_utc_2.is_err());
+        assert!(datetime_utc_3.is_err());
+        assert!(datetime_utc_4.is_err());
+        assert!(datetime_utc_5.is_err());
+        assert!(datetime_utc_6.is_err());
+        assert!(datetime_utc_7.is_err());
+        assert!(datetime_utc_8.is_err());
+    }
+}
diff --git a/backend/core/src/models/mod.rs b/backend/core/src/models/mod.rs
index b790fcb..2eb7ac2 100644
--- a/backend/core/src/models/mod.rs
+++ b/backend/core/src/models/mod.rs
@@ -5,6 +5,7 @@ pub mod category;
 pub mod category_balance;
 pub mod category_budget;
 pub mod category_transfer;
-pub mod date_time_utc;
+pub mod date_utc;
+pub mod datetime_utc;
 pub mod transaction;
 pub mod transaction_categorisation;
diff --git a/backend/core/src/models/transaction.rs b/backend/core/src/models/transaction.rs
index edfabce..18a4c0e 100644
--- a/backend/core/src/models/transaction.rs
+++ b/backend/core/src/models/transaction.rs
@@ -3,7 +3,7 @@ use diesel::prelude::*;
 
 use crate::models::account::Account;
 
-use super::date_time_utc::DateTimeUtc;
+use super::datetime_utc::DatetimeUtc;
 
 #[derive(Builder, Queryable, Identifiable, Selectable, Insertable, Associations, Debug, PartialEq)]
 #[diesel(table_name = crate::schema::transactions)]
@@ -13,6 +13,6 @@ pub struct Transaction {
     pub description: String,
     pub payee: String,
     pub quantity: i32,
-    pub date: DateTimeUtc,
+    pub date: DatetimeUtc,
     pub account_id: i32,
 }