WIP: nwc profiles

fedimint-nwc/Cargo.toml

@@ -13,6 +13,7 @@ anyhow = "1.0.75"
 axum = { version = "0.7.1", features = ["json"] }
 axum-macros = "0.4.0"
 bincode = "1.3.3"
+chrono = "0.4.38"
 clap = { version = "4.5.4", features = ["derive", "env"] }
 dotenv = "0.15.0"
 futures-util = "0.3.30"

fedimint-nwc/src/main.rs

@@ -9,6 +9,7 @@ pub mod nwc;
 pub mod server;
 pub mod services;
 pub mod state;
+pub mod utils;
 
 use crate::config::Cli;
 use crate::server::run_server;

fedimint-nwc/src/nwc/conditions.rs

@@ -0,0 +1,117 @@
+use chrono::{DateTime, Duration, NaiveDateTime, Utc};
+use lightning_invoice::Bolt11Invoice;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct SingleUseSpendingConditions {
+    pub payment_hash: Option<String>,
+    pub amount_sats: u64,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct TrackedPayment {
+    /// Time in seconds since epoch
+    pub time: u64,
+    /// Amount in sats
+    pub amt: u64,
+    /// Payment hash
+    pub hash: String,
+}
+
+/// When payments for a given payment expire
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub enum BudgetPeriod {
+    /// Resets daily at midnight UTC
+    Day,
+    /// Resets every week on sunday, midnight UTC
+    Week,
+    /// Resets every month on the first, midnight UTC
+    Month,
+    /// Resets every year on the January 1st, midnight UTC
+    Year,
+    /// Payments not older than the given number of seconds are counted
+    Seconds(u64),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct BudgetedSpendingConditions {
+    /// Amount in sats for the allotted budget period
+    pub budget: u64,
+    /// Max amount in sats for a single payment
+    pub single_max: Option<u64>,
+    /// Payment history
+    pub payments: Vec<TrackedPayment>,
+    /// Time period the budget is for
+    pub period: BudgetPeriod,
+}
+
+impl BudgetedSpendingConditions {
+    pub fn add_payment(&mut self, invoice: &Bolt11Invoice) {
+        let time = crate::utils::now().as_secs();
+        let payment = TrackedPayment {
+            time,
+            amt: invoice.amount_milli_satoshis().unwrap_or_default() / 1_000,
+            hash: invoice.payment_hash().into_32().to_lower_hex_string(),
+        };
+
+        self.payments.push(payment);
+    }
+
+    pub fn remove_payment(&mut self, invoice: &Bolt11Invoice) {
+        let hex = invoice.payment_hash().into_32().to_lower_hex_string();
+        self.payments.retain(|p| p.hash != hex);
+    }
+
+    fn clean_old_payments(&mut self, now: DateTime<Utc>) {
+        let period_start = match self.period {
+            BudgetPeriod::Day => now.date_naive().and_hms_opt(0, 0, 0).unwrap_or_default(),
+            BudgetPeriod::Week => (now
+                - Duration::days((now.weekday().num_days_from_sunday()) as i64))
+            .date_naive()
+            .and_hms_opt(0, 0, 0)
+            .unwrap_or_default(),
+            BudgetPeriod::Month => now
+                .date_naive()
+                .with_day(1)
+                .unwrap_or_default()
+                .and_hms_opt(0, 0, 0)
+                .unwrap_or_default(),
+            BudgetPeriod::Year => NaiveDateTime::new(
+                now.date_naive().with_ordinal(1).unwrap_or_default(),
+                chrono::NaiveTime::from_hms_opt(0, 0, 0).unwrap_or_default(),
+            ),
+            BudgetPeriod::Seconds(secs) => now
+                .checked_sub_signed(Duration::seconds(secs as i64))
+                .unwrap_or_default()
+                .naive_utc(),
+        };
+
+        self.payments
+            .retain(|p| p.time > period_start.timestamp() as u64)
+    }
+
+    pub fn sum_payments(&mut self) -> u64 {
+        let now = Utc::now();
+        self.clean_old_payments(now);
+        self.payments.iter().map(|p| p.amt).sum()
+    }
+
+    pub fn budget_remaining(&self) -> u64 {
+        let mut clone = self.clone();
+        self.budget.saturating_sub(clone.sum_payments())
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub enum SpendingConditions {
+    SingleUse(SingleUseSpendingConditions),
+    /// Require approval before sending a payment
+    RequireApproval,
+    Budget(BudgetedSpendingConditions),
+}
+
+impl Default for SpendingConditions {
+    fn default() -> Self {
+        Self::RequireApproval
+    }
+}

fedimint-nwc/src/nwc.rs → fedimint-nwc/src/nwc/handlers.rs

@@ -15,21 +15,11 @@ use nostr_sdk::{Event, JsonUtil};
 use tokio::spawn;
 use tracing::info;
 
+use super::types::METHODS;
 use crate::database::Database;
 use crate::services::{MultiMintService, NostrService};
 use crate::state::AppState;
 
-pub const METHODS: [Method; 8] = [
-    Method::GetInfo,
-    Method::MakeInvoice,
-    Method::GetBalance,
-    Method::LookupInvoice,
-    Method::PayInvoice,
-    Method::MultiPayInvoice,
-    Method::PayKeysend,
-    Method::MultiPayKeysend,
-];
-
 pub async fn handle_nwc_request(state: &AppState, event: Event) -> Result<(), anyhow::Error> {
     let user_keys = state.nostr_service.user_keys();
     let decrypted = nip04::decrypt(user_keys.secret_key()?, &event.pubkey, &event.content)?;

fedimint-nwc/src/nwc/mod.rs

@@ -0,0 +1,4 @@
+pub mod conditions;
+pub mod handlers;
+pub mod profiles;
+pub mod types;