Slash commands (#5718)

Co-authored-by: Douwe Osinga <douwe@squareup.com>

crates/goose/src/slash_commands.rs

@@ -0,0 +1,74 @@
+use std::path::PathBuf;
+
+use anyhow::Result;
+use serde::{Deserialize, Serialize};
+use tracing::warn;
+
+use crate::config::Config;
+use crate::recipe::Recipe;
+
+const SLASH_COMMANDS_CONFIG_KEY: &str = "slash_commands";
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SlashCommandMapping {
+    pub command: String,
+    pub recipe_path: String,
+}
+
+pub fn list_commands() -> Vec<SlashCommandMapping> {
+    Config::global()
+        .get_param(SLASH_COMMANDS_CONFIG_KEY)
+        .unwrap_or_else(|err| {
+            warn!(
+                "Failed to load {}: {}. Falling back to empty list.",
+                SLASH_COMMANDS_CONFIG_KEY, err
+            );
+            Vec::new()
+        })
+}
+
+fn save_slash_commands(commands: Vec<SlashCommandMapping>) -> Result<()> {
+    Config::global()
+        .set_param(SLASH_COMMANDS_CONFIG_KEY, &commands)
+        .map_err(|e| anyhow::anyhow!("Failed to save slash commands: {}", e))
+}
+
+pub fn set_recipe_slash_command(recipe_path: PathBuf, command: Option<String>) -> Result<()> {
+    let recipe_path_str = recipe_path.to_string_lossy().to_string();
+
+    let mut commands = list_commands();
+    commands.retain(|mapping| mapping.recipe_path != recipe_path_str);
+
+    if let Some(cmd) = command {
+        let normalized_cmd = cmd.trim_start_matches('/').to_lowercase();
+        if !normalized_cmd.is_empty() {
+            commands.push(SlashCommandMapping {
+                command: normalized_cmd,
+                recipe_path: recipe_path_str,
+            });
+        }
+    }
+
+    save_slash_commands(commands)
+}
+
+pub fn get_recipe_for_command(command: &str) -> Option<PathBuf> {
+    let normalized = command.trim_start_matches('/').to_lowercase();
+    let commands = list_commands();
+    commands
+        .into_iter()
+        .find(|mapping| mapping.command == normalized)
+        .map(|mapping| PathBuf::from(mapping.recipe_path))
+}
+
+pub fn resolve_slash_command(command: &str) -> Option<Recipe> {
+    let recipe_path = get_recipe_for_command(command)?;
+
+    if !recipe_path.exists() {
+        return None;
+    }
+    let recipe_content = std::fs::read_to_string(&recipe_path).ok()?;
+    let recipe = Recipe::from_content(&recipe_content).ok()?;
+
+    Some(recipe)
+}