//! `milestone list|create|close` — manage milestones. Default action:
//! list.

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

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

#[derive(ClapArgs)]
pub struct Args {
    #[command(subcommand)]
    action: Option<Action>,
}

#[derive(Subcommand)]
enum Action {
    /// List open milestones as JSON.
    List,
    /// Create a milestone, print {id,title}.
    Create {
        /// Milestone title.
        #[arg(long)]
        title: String,
        /// Description.
        #[arg(long)]
        desc: Option<String>,
        /// Due date YYYY-MM-DD.
        #[arg(long)]
        due: Option<String>,
    },
    /// Close a milestone by id.
    Close {
        /// Milestone id.
        id: u64,
    },
}

pub fn run(client: &Client, args: Args) -> Result<()> {
    let repo = client.repo();
    match args.action.unwrap_or(Action::List) {
        Action::List => {
            let v = client.get_json(&format!("/repos/{repo}/milestones?state=open&limit=50"))?;
            let trimmed: Vec<Value> = v
                .as_array()
                .map(|a| {
                    a.iter()
                        .map(|m| {
                            json!({
                                "id": m.get("id"),
                                "title": m.get("title"),
                                "open_issues": m.get("open_issues"),
                                "closed_issues": m.get("closed_issues"),
                                "due_on": m.get("due_on"),
                                "description": m.get("description"),
                            })
                        })
                        .collect()
                })
                .unwrap_or_default();
            print_json(&Value::Array(trimmed))
        }
        Action::Create { title, desc, due } => {
            let mut payload = json!({ "title": title });
            if let Some(d) = desc.filter(|s| !s.is_empty()) {
                payload["description"] = Value::String(d);
            }
            if let Some(d) = due.filter(|s| !s.is_empty()) {
                payload["due_on"] = Value::String(format!("{d}T00:00:00Z"));
            }
            let resp = client.post_json(&format!("/repos/{repo}/milestones"), &payload)?;
            print_json(&json!({
                "id": resp.get("id"),
                "title": resp.get("title"),
            }))
        }
        Action::Close { id } => {
            let resp = client.patch_json(
                &format!("/repos/{repo}/milestones/{id}"),
                &json!({ "state": "closed" }),
            )?;
            print_json(&json!({
                "id": resp.get("id"),
                "title": resp.get("title"),
                "state": resp.get("state"),
            }))
        }
    }
}