Refactors some backend stuff to core lib

17 files changed, 1073 insertions, 0 deletions

diff --git a/backend/core/2024-08-31-084439_initial_setup/down.sql b/backend/core/2024-08-31-084439_initial_setup/down.sql
new file mode 100644
index 0000000..8cf4b1e
--- /dev/null
+++ b/backend/core/2024-08-31-084439_initial_setup/down.sql
@@ -0,0 +1,6 @@
+DROP TABLE accounts;
+DROP TABLE budget_updates;
+DROP TABLE categories;
+DROP TABLE transaction_categorisations;
+DROP TABLE category_transfers;
+DROP TABLE transactions;
diff --git a/backend/core/2024-08-31-084439_initial_setup/up.sql b/backend/core/2024-08-31-084439_initial_setup/up.sql
new file mode 100644
index 0000000..3584ae7
--- /dev/null
+++ b/backend/core/2024-08-31-084439_initial_setup/up.sql
@@ -0,0 +1,70 @@
+PRAGMA foreign_keys = ON;
+
+CREATE TABLE accounts(
+    id INTEGER NOT NULL PRIMARY KEY,
+    name TEXT NOT NULL,
+    opening_balance INTEGER NOT NULL,
+    opening_date TEXT NOT NULL
+);
+
+CREATE TABLE budget_updates(
+    id INTEGER NOT NULL PRIMARY KEY,
+    category_id INTEGER NOT NULL,
+    date TEXT NOT NULL,
+    new_budget INTEGER NOT NULL,
+    new_period INTEGER NOT NULL,
+    FOREIGN KEY (category_id)
+        REFERENCES categories (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT
+);
+
+CREATE TABLE categories(
+    id INTEGER NOT NULL PRIMARY KEY,
+    name TEXT NOT NULL
+);
+
+CREATE TABLE category_transfers(
+    id INTEGER NOT NULL PRIMARY KEY,
+    description TEXT NOT NULL,
+    quantity INTEGER NOT NULL,
+    from_category_id INTEGER NOT NULL,
+    to_category_id INTEGER NOT NULL,
+    FOREIGN KEY (from_category_id)
+        REFERENCES categories (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT,
+    FOREIGN KEY (to_category_id)
+        REFERENCES categories (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT
+);
+
+CREATE TABLE transactions(
+    id INTEGER NOT NULL PRIMARY KEY,
+    description TEXT NOT NULL,
+    payee TEXT NOT NULL,
+    quantity INTEGER NOT NULL,
+    date TEXT NOT NULL,
+    account_id INTEGER NOT NULL,
+    FOREIGN KEY (account_id)
+        REFERENCES accounts (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT
+);
+
+CREATE TABLE transaction_categorisations(
+    id INTEGER NOT NULL PRIMARY KEY,
+    description TEXT NOT NULL,
+    quantity INTEGER NOT NULL,
+    transaction_id INTEGER NOT NULL,
+    category_id INTEGER NOT NULL,
+    FOREIGN KEY (transaction_id)
+        REFERENCES transactions (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT,
+    FOREIGN KEY (category_id)
+        REFERENCES categories (id)
+        ON UPDATE CASCADE
+        ON DELETE RESTRICT
+);
diff --git a/backend/core/Cargo.lock b/backend/core/Cargo.lock
new file mode 100644
index 0000000..0a4e0fd
--- /dev/null
+++ b/backend/core/Cargo.lock
@@ -0,0 +1,628 @@
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+ "quote",
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+]
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+ "proc-macro2",
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+ "syn",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
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+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
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+
+[[package]]
+name = "winnow"
+version = "0.6.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36c1fec1a2bb5866f07c25f68c26e565c4c200aebb96d7e55710c19d3e8ac49b"
+dependencies = [
+ "memchr",
+]
diff --git a/backend/core/Cargo.toml b/backend/core/Cargo.toml
new file mode 100644
index 0000000..09b1ebf
--- /dev/null
+++ b/backend/core/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "budgeting_app_core"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+chrono = { version = "0.4.38", features = ["serde"] }
+diesel = { version = "2.2.0", features = ["sqlite"] }
+diesel_migrations = "2.2.0"
+serde = { version = "1.0.209",  features = ["derive"] }
diff --git a/backend/core/src/lib.rs b/backend/core/src/lib.rs
new file mode 100644
index 0000000..7a56560
--- /dev/null
+++ b/backend/core/src/lib.rs
@@ -0,0 +1,6 @@
+use diesel_migrations::{embed_migrations, EmbeddedMigrations};
+
+pub mod models;
+pub mod schema;
+
+pub const MIGRATIONS: EmbeddedMigrations = embed_migrations!("migrations");
diff --git a/backend/core/src/models/account.rs b/backend/core/src/models/account.rs
new file mode 100644
index 0000000..c10bd5f
--- /dev/null
+++ b/backend/core/src/models/account.rs
@@ -0,0 +1,15 @@
+use diesel::prelude::*;
+use serde::{Deserialize, Serialize};
+
+use super::date_time_utc::DateTimeUtc;
+
+#[derive(
+    Insertable, Queryable, Identifiable, Selectable, Debug, PartialEq, Clone, Serialize, Deserialize,
+)]
+#[diesel(table_name = crate::schema::accounts)]
+pub struct Account {
+    pub id: i32,
+    pub name: String,
+    pub opening_balance: i32,
+    pub opening_date: DateTimeUtc,
+}
diff --git a/backend/core/src/models/budget.rs b/backend/core/src/models/budget.rs
new file mode 100644
index 0000000..cc18f2e
--- /dev/null
+++ b/backend/core/src/models/budget.rs
@@ -0,0 +1,44 @@
+use serde::Serialize;
+
+use super::budget_update::BudgetUpdate;
+
+#[derive(Debug, Eq, PartialEq, Serialize)]
+pub struct Budget {
+    pub quantity: i32,
+    pub period: i32,
+}
+
+impl From<&BudgetUpdate> for Budget {
+    fn from(budget_update: &BudgetUpdate) -> Self {
+        Self {
+            quantity: budget_update.new_budget,
+            period: budget_update.new_period,
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use chrono::Utc;
+
+    use crate::models::date_time_utc::DateTimeUtc;
+
+    use super::*;
+
+    #[test]
+    fn when_from_budget_update_then_returns_budget() {
+        let quantity = 2;
+        let period = 3;
+        let budget_update = BudgetUpdate {
+            id: 0,
+            category_id: 1,
+            date: DateTimeUtc::new(Utc::now()),
+            new_budget: quantity,
+            new_period: period,
+        };
+
+        let budget = Budget::from(&budget_update);
+
+        assert_eq!(budget, Budget { quantity, period });
+    }
+}
diff --git a/backend/core/src/models/budget_update.rs b/backend/core/src/models/budget_update.rs
new file mode 100644
index 0000000..c63e957
--- /dev/null
+++ b/backend/core/src/models/budget_update.rs
@@ -0,0 +1,17 @@
+use diesel::prelude::*;
+use serde::Serialize;
+
+use crate::models::category::Category;
+
+use super::date_time_utc::DateTimeUtc;
+
+#[derive(Clone, Serialize, Queryable, Identifiable, Selectable, Associations, Debug, PartialEq)]
+#[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 new_budget: i32,
+    pub new_period: i32,
+}
diff --git a/backend/core/src/models/category.rs b/backend/core/src/models/category.rs
new file mode 100644
index 0000000..5cb2609
--- /dev/null
+++ b/backend/core/src/models/category.rs
@@ -0,0 +1,9 @@
+use diesel::prelude::*;
+use serde::{Deserialize, Serialize};
+
+#[derive(Queryable, Identifiable, Selectable, Debug, PartialEq, Serialize, Deserialize)]
+#[diesel(table_name = crate::schema::categories)]
+pub struct Category {
+    pub id: i32,
+    pub name: String,
+}
diff --git a/backend/core/src/models/category_balance.rs b/backend/core/src/models/category_balance.rs
new file mode 100644
index 0000000..796b40b
--- /dev/null
+++ b/backend/core/src/models/category_balance.rs
@@ -0,0 +1,7 @@
+use serde::Serialize;
+
+#[derive(Serialize)]
+pub struct CategoryBalance {
+    pub category_id: i32,
+    pub balance: i32,
+}
diff --git a/backend/core/src/models/category_budget.rs b/backend/core/src/models/category_budget.rs
new file mode 100644
index 0000000..9796261
--- /dev/null
+++ b/backend/core/src/models/category_budget.rs
@@ -0,0 +1,9 @@
+use serde::Serialize;
+
+use super::budget::Budget;
+
+#[derive(Serialize)]
+pub struct CategoryBudget {
+    pub category_id: i32,
+    pub budget: Option<Budget>,
+}
diff --git a/backend/core/src/models/category_transfer.rs b/backend/core/src/models/category_transfer.rs
new file mode 100644
index 0000000..6cbda0e
--- /dev/null
+++ b/backend/core/src/models/category_transfer.rs
@@ -0,0 +1,11 @@
+use diesel::prelude::*;
+
+#[derive(Queryable, Identifiable, Selectable, Debug, PartialEq)]
+#[diesel(table_name = crate::schema::category_transfers)]
+pub struct CategoryTransfer {
+    pub id: i32,
+    pub description: String,
+    pub quantity: i32,
+    pub from_category_id: i32,
+    pub to_category_id: i32,
+}
diff --git a/backend/core/src/models/date_time_utc.rs b/backend/core/src/models/date_time_utc.rs
new file mode 100644
index 0000000..03d5802
--- /dev/null
+++ b/backend/core/src/models/date_time_utc.rs
@@ -0,0 +1,131 @@
+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,
+    Copy,
+    Clone,
+    Debug,
+    AsExpression,
+    FromSqlRow,
+)]
+#[diesel(sql_type=Text)]
+pub struct DateTimeUtc(DateTime<Utc>);
+
+impl DateTimeUtc {
+    pub fn day_diff(&self, other: &DateTimeUtc) -> u32 {
+        self.0
+            .num_days_from_ce()
+            .abs_diff(other.0.num_days_from_ce())
+    }
+
+    pub fn to_day_str(&self) -> String {
+        self.0
+            .to_rfc3339()
+            .split_at_checked(10)
+            .map(|(day_str, _)| String::from(day_str))
+            .unwrap_or_else(|| String::from(""))
+    }
+
+    pub fn new(date_time_utc: DateTime<Utc>) -> Self {
+        Self(date_time_utc)
+    }
+
+    pub fn now() -> Self {
+        Self(Utc::now())
+    }
+}
+
+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_day_str());
+        Ok(diesel::serialize::IsNull::No)
+    }
+}
+
+impl FromSql<Text, Sqlite> for DateTimeUtc {
+    fn from_sql(bytes: <Sqlite as Backend>::RawValue<'_>) -> deserialize::Result<DateTimeUtc> {
+        let str: String = FromSql::<Text, Sqlite>::from_sql(bytes)?;
+        let date_time = str.as_str().parse::<DateTime<Utc>>()?;
+        Ok(DateTimeUtc(date_time))
+    }
+}
+
+#[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(),
+        );
+        let day_str = date_time_utc.to_day_str();
+
+        assert_eq!(day_str, "1970-11-23");
+    }
+}
diff --git a/backend/core/src/models/mod.rs b/backend/core/src/models/mod.rs
new file mode 100644
index 0000000..b790fcb
--- /dev/null
+++ b/backend/core/src/models/mod.rs
@@ -0,0 +1,10 @@
+pub mod account;
+pub mod budget;
+pub mod budget_update;
+pub mod category;
+pub mod category_balance;
+pub mod category_budget;
+pub mod category_transfer;
+pub mod date_time_utc;
+pub mod transaction;
+pub mod transaction_categorisation;
diff --git a/backend/core/src/models/transaction.rs b/backend/core/src/models/transaction.rs
new file mode 100644
index 0000000..36f33f8
--- /dev/null
+++ b/backend/core/src/models/transaction.rs
@@ -0,0 +1,17 @@
+use diesel::prelude::*;
+
+use crate::models::account::Account;
+
+use super::date_time_utc::DateTimeUtc;
+
+#[derive(Queryable, Identifiable, Selectable, Associations, Debug, PartialEq)]
+#[diesel(table_name = crate::schema::transactions)]
+#[diesel(belongs_to(Account))]
+pub struct Transaction {
+    pub id: i32,
+    pub description: String,
+    pub payee: String,
+    pub quantity: i32,
+    pub date: DateTimeUtc,
+    pub account_id: i32,
+}
diff --git a/backend/core/src/models/transaction_categorisation.rs b/backend/core/src/models/transaction_categorisation.rs
new file mode 100644
index 0000000..60c2b98
--- /dev/null
+++ b/backend/core/src/models/transaction_categorisation.rs
@@ -0,0 +1,11 @@
+use diesel::prelude::*;
+
+#[derive(Queryable, Identifiable, Selectable, Debug, PartialEq)]
+#[diesel(table_name = crate::schema::transaction_categorisations)]
+pub struct TransactionCategorisation {
+    pub id: i32,
+    pub description: String,
+    pub quantity: i32,
+    pub transaction_id: i32,
+    pub category_id: i32,
+}
diff --git a/backend/core/src/schema.rs b/backend/core/src/schema.rs
new file mode 100644
index 0000000..372f8f3
--- /dev/null
+++ b/backend/core/src/schema.rs
@@ -0,0 +1,72 @@
+// @generated automatically by Diesel CLI.
+
+diesel::table! {
+    accounts (id) {
+        id -> Integer,
+        name -> Text,
+        opening_balance -> Integer,
+        opening_date -> Text,
+    }
+}
+
+diesel::table! {
+    budget_updates (id) {
+        id -> Integer,
+        category_id -> Integer,
+        date -> Text,
+        new_budget -> Integer,
+        new_period -> Integer,
+    }
+}
+
+diesel::table! {
+    categories (id) {
+        id -> Integer,
+        name -> Text,
+    }
+}
+
+diesel::table! {
+    category_transfers (id) {
+        id -> Integer,
+        description -> Text,
+        quantity -> Integer,
+        from_category_id -> Integer,
+        to_category_id -> Integer,
+    }
+}
+
+diesel::table! {
+    transaction_categorisations (id) {
+        id -> Integer,
+        description -> Text,
+        quantity -> Integer,
+        transaction_id -> Integer,
+        category_id -> Integer,
+    }
+}
+
+diesel::table! {
+    transactions (id) {
+        id -> Integer,
+        description -> Text,
+        payee -> Text,
+        quantity -> Integer,
+        date -> Text,
+        account_id -> Integer,
+    }
+}
+
+diesel::joinable!(budget_updates -> categories (category_id));
+diesel::joinable!(transaction_categorisations -> categories (category_id));
+diesel::joinable!(transaction_categorisations -> transactions (transaction_id));
+diesel::joinable!(transactions -> accounts (account_id));
+
+diesel::allow_tables_to_appear_in_same_query!(
+    accounts,
+    budget_updates,
+    categories,
+    category_transfers,
+    transaction_categorisations,
+    transactions,
+);