//! `repo-labels [pattern]` — list the active repo's full label set
//! (project-wide), not the labels on one issue/PR (that's `labels
//! <number>`). Useful for triage / labelling to discover the valid label
//! names + what each means before applying them.

use anyhow::Result;
use clap::Args as ClapArgs;
use serde_json::{Value, json};

use crate::client::Client;
use crate::verbs::print_json;

#[derive(ClapArgs)]
pub struct Args {
    /// Substring pattern to filter label names (case-sensitive).
    pattern: Option<String>,
}

pub fn run(client: &Client, args: Args) -> Result<()> {
    let repo = client.repo();
    // Repos can carry more than one page of labels; paginate so the list
    // is complete rather than capped at the first page.
    let labels = client.get_json_all(&format!("/repos/{repo}/labels"), 10)?;
    let filtered: Vec<&Value> = labels
        .iter()
        .filter(|l| {
            let name = l.get("name").and_then(Value::as_str).unwrap_or_default();
            args.pattern.as_deref().is_none_or(|p| name.contains(p))
        })
        .collect();

    if client.json_mode() {
        // Full label objects (id, name, color, description) as a JSON array.
        print_json(&json!(filtered))?;
    } else {
        // One label per line: `name`, plus its description (tab-separated)
        // when set, so triage can see what each label means at a glance.
        for l in filtered {
            let name = l.get("name").and_then(Value::as_str).unwrap_or_default();
            let desc = l
                .get("description")
                .and_then(Value::as_str)
                .unwrap_or_default();
            if desc.is_empty() {
                println!("{name}");
            } else {
                println!("{name}\t{desc}");
            }
        }
    }
    Ok(())
}