feat: create a task model

src/models/category.rs

@@ -0,0 +1,65 @@
+use chrono::{Duration, NaiveDate, NaiveTime};
+use diesel::deserialize::FromSql;
+use diesel::pg::{Pg, PgValue};
+use diesel::serialize::{Output, ToSql};
+use diesel::sql_types::Jsonb;
+use diesel::{AsExpression, FromSqlRow};
+use serde::{Deserialize, Serialize};
+use serde_with::DurationSeconds;
+use std::io::Write;
+
+#[serde_with::serde_as]
+#[derive(AsExpression, FromSqlRow, Serialize, Deserialize, Clone, Debug)]
+#[diesel(sql_type = Jsonb)]
+pub enum Category {
+    Inbox,
+    SomedayMaybe,
+    WaitingFor(String),
+    NextSteps,
+    Calendar {
+        date: NaiveDate,
+        #[serde_as(as = "Option<DurationSeconds<i64>>")]
+        reoccurance_interval: Option<Duration>,
+        time: Option<CalendarTime>,
+    },
+    LongTerm,
+    Done,
+    Trash,
+}
+
+#[serde_with::serde_as]
+#[derive(Serialize, Deserialize, Clone, Debug)]
+pub struct CalendarTime {
+    time: NaiveTime,
+    #[serde_as(as = "Option<DurationSeconds<i64>>")]
+    reminder_offset: Option<Duration>,
+}
+
+impl CalendarTime {
+    pub fn new(time: NaiveTime, reminder_offset: Option<Duration>) -> Self {
+        Self { time, reminder_offset }
+    }
+}
+
+impl ToSql<Jsonb, Pg> for Category {
+    fn to_sql<'b>(&'b self, out: &mut Output<'b, '_, Pg>) -> diesel::serialize::Result {
+        let json = serde_json::to_string(self)?;
+
+        // Prepend the JSONB version byte.
+        out.write_all(&[1])?;
+        out.write_all(json.as_bytes())?;
+
+        Ok(diesel::serialize::IsNull::No)
+    }
+}
+
+impl FromSql<Jsonb, Pg> for Category {
+    fn from_sql(bytes: PgValue) -> diesel::deserialize::Result<Self> {
+        let bytes = bytes.as_bytes();
+        if bytes.is_empty() {
+            return Err("Unexpected empty bytes (missing the JSONB version number).".into());
+        }
+        let str = std::str::from_utf8(&bytes[1..])?;
+        serde_json::from_str(str).map_err(Into::into)
+    }
+}