1 files changed, 81 insertions, 0 deletions
diff --git a/src/cli.rs b/src/cli.rs
new file mode 100644
index 0000000..0bd0a78
--- /dev/null
+++ b/src/cli.rs
@@ -0,0 +1,81 @@
+use std::path::PathBuf;
+use clap::{Subcommand, Parser, ValueHint};
+use std::env;
+
+#[derive(Debug, Parser)]
+#[command(version, about, long_about = None)]
+pub struct Cli {
+    /// file path where data is stored [default:
+    /// $XDG_DATA_HOME/debt/debt.db
+    #[arg(short, long, env="DEBT_DB", value_hint = ValueHint::FilePath)]
+    pub database_path: Option<PathBuf>,
+
+    #[command(subcommand)] 
+    pub action: Commands
+}
+
+#[derive(Debug, Subcommand)]
+pub enum Commands {
+    /// Initialize Database
+    Init,
+    /// Register a transaction
+    Register {
+        /// person to register the transaction
+        person: String,
+
+        /// amount of money
+        amount: i32,
+
+        /// additional notes
+        note: Option<String>,
+
+        /// Register the transaction as a payment
+        #[arg(short, long)]
+        payment: bool
+    },
+
+    View {
+        filter: Option<String>,
+        /// View register history
+        #[arg(short='H', long)]
+        history: bool,
+        /// Transaction accumulation by person
+        #[arg(short, long)]
+        total: bool
+    },
+
+    /// Add a new agent to lend or pay
+    Add {
+        name: String,
+    },
+}
+
+impl Cli {
+    pub fn new() -> Self {
+        let mut cli = Cli::parse();
+        load_datapath(&mut cli);
+        cli
+    }
+}
+
+fn load_datapath(cli: &mut Cli) {
+    let config_path = cli
+        .database_path
+        .clone()
+        .or_else(|| {
+            xdg::BaseDirectories::with_prefix("debt")
+                .ok()
+                .and_then(|x| {
+                    x.find_data_file("cache.db")
+                })
+        }).or_else(|| {
+            if let Ok(home) = env::var("HOME") {
+                let fallback = PathBuf::from(&home).join(".debt.db");
+                if fallback.exists() {
+                    return Some(fallback)
+                }
+            }
+            None
+        });
+    cli.database_path = config_path;
+}