//! theme: switch the active color theme and persist it for the next start.
//!
//! With no argument, prints the current theme and the available list.
//! With a name, switches to that theme (also used by the REPL 'theme' command).

use super::*;
use crate::theme;

pub fn run(app: &App, name: Option<&str>) -> Result<i32> {
    if let Some(name) = name {
        let theme = theme::find(name).ok_or_else(|| {
            anyhow::anyhow!(
                "unknown theme '{name}' — available: {}",
                theme::names().join(", ")
            )
        })?;
        app.set_theme(theme);
        crate::commands::config_cmd::persist_setting(app, "settings.theme", theme.name)?;
        app.log.success(&format!(
            "theme set to {} ({})",
            theme.name,
            theme.title
        ));
        return Ok(0);
    }

    // No argument: show current and list.
    let current = app.theme();
    if app.json() {
        crate::output::print_json(&serde_json::json!({
            "current": current.name,
            "title": current.title,
            "available": theme::names(),
        }));
    } else {
        println!("current theme: {} — {}", current.name, current.title);
        println!("available themes: {}", theme::names().join(", "));
        println!("use 'am theme <name>' to switch");
    }
    Ok(0)
}