Account for zero budgets not carried over

when transforming bucket transactions from Actualbudget

3 files changed, 366 insertions, 8 deletions

diff --git a/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state.rs b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state.rs
index ae560c6..6101403 100644
--- a/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state.rs
+++ b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state.rs
@@ -2,6 +2,7 @@ mod is_account_transfer;
 mod is_category_transfer;
 mod transform_account_transfers;
 mod transform_accounts;
+mod transform_bucket_transactions_from_budgets_not_carried_over;
 mod transform_bucket_transactions_from_category_transfers;
 mod transform_categories_to_buckets;
 mod transform_date;
@@ -17,6 +18,7 @@ use is_category_transfer::is_category_transfer;
 use is_category_transfer::is_not_category_transfer;
 use transform_account_transfers::transform_account_transfers;
 use transform_accounts::transform_accounts;
+use transform_bucket_transactions_from_budgets_not_carried_over::transform_bucket_transactions_from_budgets_not_carried_over;
 use transform_bucket_transactions_from_category_transfers::transform_bucket_transactions_from_category_transfers;
 use transform_categories_to_buckets::transform_categories_to_buckets;
 use transform_date::transform_date;
diff --git a/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_bucket_transactions_from_budgets_not_carried_over.rs b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_bucket_transactions_from_budgets_not_carried_over.rs
new file mode 100644
index 0000000..6001153
--- /dev/null
+++ b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_bucket_transactions_from_budgets_not_carried_over.rs
@@ -0,0 +1,350 @@
+use std::collections::HashMap;
+
+use actualbudget_models::{ActualbudgetDate, ActualbudgetTransaction, ActualbudgetZeroBudget};
+use anyhow::Result;
+use itertools::Itertools;
+use schist_models::bucket_transaction::BucketTransaction;
+use schist_traits::dateable::Dateable;
+
+use crate::transform_state::{transform_date, transform_id};
+
+pub fn transform_bucket_transactions_from_budgets_not_carried_over(
+    actualbudget_zero_budgets: &[ActualbudgetZeroBudget],
+    actualbudget_transactions: &[ActualbudgetTransaction],
+) -> Result<Vec<BucketTransaction>> {
+    let budgets_not_carried_over: Vec<&ActualbudgetZeroBudget> = actualbudget_zero_budgets
+        .iter()
+        .filter(|zb| !zb.do_carry_over)
+        .sorted_unstable_by_key(|zb| zb.month)
+        .collect();
+    let mut last_reset_to_zero_per_category_id: HashMap<String, ActualbudgetDate> =
+        HashMap::from_iter(
+            budgets_not_carried_over
+                .iter()
+                .unique_by(|zb| zb.category_id.clone())
+                .map(|zb| {
+                    (
+                        zb.category_id.clone(),
+                        ActualbudgetDate::oldest_valid_date(),
+                    )
+                }),
+        );
+
+    let mut bucket_transactions = Vec::new();
+    for budget in budgets_not_carried_over {
+        let last_not_carried_over_month_start: ActualbudgetDate =
+            last_reset_to_zero_per_category_id
+                .get(&budget.category_id)
+                .cloned()
+                .unwrap_or_else(|| ActualbudgetDate::oldest_valid_date());
+        let start_of_next_month = transform_date(&budget.month)?.first_day_in_next_month();
+        let actualbudget_start_of_next_month = ActualbudgetDate::from_ymd(
+            start_of_next_month.year(),
+            start_of_next_month.month(),
+            start_of_next_month.day(),
+        );
+
+        let balance_from_zero_budgets: i32 = actualbudget_zero_budgets
+            .iter()
+            .filter(|zb| {
+                zb.category_id == budget.category_id
+                    && zb.month >= last_not_carried_over_month_start
+                    && zb.month < actualbudget_start_of_next_month
+            })
+            .map(|zb| zb.amount)
+            .sum();
+        let balance_from_transactions: i32 = actualbudget_transactions
+            .iter()
+            .filter(|t| {
+                t.category_id
+                    .as_ref()
+                    .is_some_and(|id| *id == budget.category_id)
+                    && t.date >= last_not_carried_over_month_start
+                    && t.date < actualbudget_start_of_next_month
+            })
+            .map(|t| t.amount)
+            .sum();
+        let balance_at_end_of_month = balance_from_zero_budgets + balance_from_transactions;
+
+        if balance_at_end_of_month < 0 {
+            last_reset_to_zero_per_category_id
+                .insert(budget.category_id.clone(), actualbudget_start_of_next_month);
+            bucket_transactions.push(BucketTransaction {
+                id: transform_id(&budget.id),
+                description: format!("Actualbudget budget <{}> not carried over", budget.id),
+                date: start_of_next_month,
+                quantity: -balance_at_end_of_month,
+                bucket_id: transform_id(&budget.category_id),
+            });
+        }
+    }
+
+    Ok(bucket_transactions)
+}
+
+#[cfg(test)]
+mod test {
+    use actualbudget_fakes::{
+        actualbudget_transaction::make_fake_actualbudget_transaction_builder,
+        actualbudget_zero_budget::make_fake_actualbudget_zero_budget_builder,
+    };
+    use actualbudget_models::ActualbudgetDate;
+    use schist_models::{bucket_transaction::BucketTransaction, date_utc::DateUtc};
+
+    use crate::transform_state::{
+        transform_bucket_transactions_from_budgets_not_carried_over::transform_bucket_transactions_from_budgets_not_carried_over,
+        transform_id::transform_id,
+    };
+
+    #[test]
+    fn no_resets() {
+        let actualbudget_zero_budgets = [
+            make_fake_actualbudget_zero_budget_builder("zb0")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202601))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb1")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202602))
+                .build()
+                .unwrap(),
+        ];
+
+        let actualbudget_transactions = [
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 1))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 31))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t1")
+                .category_id(Some(String::from("c1")))
+                .amount(-101)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 21))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t1")
+                .category_id(Some(String::from("c1")))
+                .amount(-101)
+                .date(ActualbudgetDate::from_ymd(2026, 2, 21))
+                .build()
+                .unwrap(),
+        ];
+
+        let result = transform_bucket_transactions_from_budgets_not_carried_over(
+            &actualbudget_zero_budgets,
+            &actualbudget_transactions,
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert_eq!(Vec::<BucketTransaction>::new(), result);
+    }
+
+    #[test]
+    fn one_reset() {
+        let actualbudget_zero_budgets = [
+            make_fake_actualbudget_zero_budget_builder("zb0")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202601))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb1")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202602))
+                .build()
+                .unwrap(),
+        ];
+
+        let actualbudget_transactions = [
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 1))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-51)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 31))
+                .build()
+                .unwrap(),
+        ];
+
+        let result = transform_bucket_transactions_from_budgets_not_carried_over(
+            &actualbudget_zero_budgets,
+            &actualbudget_transactions,
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert_eq!(result.len(), 1);
+        let transaction = result.first().unwrap();
+        assert_eq!(transaction.quantity, 1);
+        assert_eq!(transaction.bucket_id, transform_id("c0"));
+        assert_eq!(transaction.date, DateUtc::from_ymd(2026, 2, 1).unwrap());
+    }
+
+    #[test]
+    fn two_resets() {
+        let actualbudget_zero_budgets = [
+            make_fake_actualbudget_zero_budget_builder("zb0")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202401))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb1")
+                .category_id(String::from("c0"))
+                .amount(101)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202402))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb2")
+                .category_id(String::from("c0"))
+                .amount(102)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202403))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb3")
+                .category_id(String::from("c0"))
+                .amount(103)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202404))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb4")
+                .category_id(String::from("c0"))
+                .amount(104)
+                .do_carry_over(false)
+                .month(ActualbudgetDate::from_i32(202405))
+                .build()
+                .unwrap(),
+        ];
+
+        let actualbudget_transactions = [
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2024, 1, 1))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t1")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2024, 1, 31))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t2")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2024, 2, 1))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t3")
+                .category_id(Some(String::from("c0")))
+                .amount(-53)
+                .date(ActualbudgetDate::from_ymd(2024, 2, 29))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t4")
+                .category_id(Some(String::from("c0")))
+                .amount(-92)
+                .date(ActualbudgetDate::from_ymd(2024, 3, 15))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t5")
+                .category_id(Some(String::from("c0")))
+                .amount(-93)
+                .date(ActualbudgetDate::from_ymd(2024, 4, 15))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t6")
+                .category_id(Some(String::from("c0")))
+                .amount(-127)
+                .date(ActualbudgetDate::from_ymd(2024, 5, 15))
+                .build()
+                .unwrap(),
+        ];
+
+        let result = transform_bucket_transactions_from_budgets_not_carried_over(
+            &actualbudget_zero_budgets,
+            &actualbudget_transactions,
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert_eq!(result.len(), 2);
+
+        let transaction = result.iter().find(|bt| bt.quantity == 2);
+        assert!(transaction.is_some());
+        let transaction = transaction.unwrap();
+        assert_eq!(transaction.quantity, 2);
+        assert_eq!(transaction.bucket_id, transform_id("c0"));
+        assert_eq!(transaction.date, DateUtc::from_ymd(2024, 3, 1).unwrap());
+
+        let transaction = result.iter().find(|bt| bt.quantity == 3);
+        assert!(transaction.is_some());
+        let transaction = transaction.unwrap();
+        assert_eq!(transaction.bucket_id, transform_id("c0"));
+        assert_eq!(transaction.date, DateUtc::from_ymd(2024, 6, 1).unwrap());
+    }
+
+    #[test]
+    fn carried_over() {
+        let actualbudget_zero_budgets = [
+            make_fake_actualbudget_zero_budget_builder("zb0")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(true)
+                .month(ActualbudgetDate::from_i32(202601))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_zero_budget_builder("zb1")
+                .category_id(String::from("c0"))
+                .amount(100)
+                .do_carry_over(true)
+                .month(ActualbudgetDate::from_i32(202602))
+                .build()
+                .unwrap(),
+        ];
+
+        let actualbudget_transactions = [
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-50)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 1))
+                .build()
+                .unwrap(),
+            make_fake_actualbudget_transaction_builder("t0")
+                .category_id(Some(String::from("c0")))
+                .amount(-51)
+                .date(ActualbudgetDate::from_ymd(2026, 1, 31))
+                .build()
+                .unwrap(),
+        ];
+
+        let result = transform_bucket_transactions_from_budgets_not_carried_over(
+            &actualbudget_zero_budgets,
+            &actualbudget_transactions,
+        );
+        assert!(result.is_ok());
+        let result = result.unwrap();
+        assert_eq!(result.len(), 0);
+    }
+}
diff --git a/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_state.rs b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_state.rs
index d3ebee5..0d21a71 100644
--- a/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_state.rs
+++ b/transformers/actualbudget_transformer/actualbudget_to_schist_transformer/src/transform_state/transform_state.rs
@@ -1,7 +1,10 @@
 use anyhow::{Context, Result};
 use schist_models::{Account, Bucket, BucketTransaction, Pipe, Transaction};
 
-use crate::{actualbudget_state::ActualbudgetState, schist_state::SchistState};
+use crate::{
+    actualbudget_state::ActualbudgetState, schist_state::SchistState,
+    transform_state::transform_bucket_transactions_from_budgets_not_carried_over,
+};
 
 use super::{
     transform_account_transfers, transform_accounts,
@@ -37,13 +40,16 @@ fn transform_state_without_context(actualbudget_state: ActualbudgetState) -> Res
     );
     let pipes: Vec<Pipe> =
         transform_zero_budgets_to_pipes(&actualbudget_state.actualbudget_zero_budgets)?;
-    let bucket_transactions: Vec<BucketTransaction> =
-        vec![transform_bucket_transactions_from_category_transfers(
-            &remaining_transactions,
-        )?]
-        .into_iter()
-        .flatten()
-        .collect();
+    let bucket_transactions: Vec<BucketTransaction> = vec![
+        transform_bucket_transactions_from_category_transfers(&remaining_transactions)?,
+        transform_bucket_transactions_from_budgets_not_carried_over(
+            &actualbudget_state.actualbudget_zero_budgets,
+            &actualbudget_state.actualbudget_transactions,
+        )?,
+    ]
+    .into_iter()
+    .flatten()
+    .collect();
 
     Ok(SchistState {
         first_transaction_date: first_activity_date,