//! `tree-sha <ref> [repo]` — print the tree SHA of the commit at a
//! branch name or commit SHA.

use anyhow::Result;
use clap::Args as ClapArgs;
use serde_json::Value;

use crate::client::Client;

#[derive(ClapArgs)]
pub struct Args {
    /// Branch name or commit SHA.
    reference: String,
}

pub fn run(client: &Client, args: Args) -> Result<()> {
    let repo = client.repo();
    // Try branch first; the bash helper silently treats failure as
    // "not a branch, use the reference as a commit sha directly".
    let commit_sha = match client.get_json(&format!("/repos/{repo}/branches/{}", args.reference)) {
        Ok(v) => v
            .get("commit")
            .and_then(|c| c.get("id"))
            .and_then(Value::as_str)
            .unwrap_or(&args.reference)
            .to_owned(),
        Err(_) => args.reference.clone(),
    };
    let commit = client.get_json(&format!("/repos/{repo}/git/commits/{commit_sha}"))?;
    let sha = commit
        .get("tree")
        .and_then(|t| t.get("sha"))
        .and_then(Value::as_str)
        .or_else(|| commit.get("sha").and_then(Value::as_str))
        .unwrap_or("");
    println!("{sha}");
    Ok(())
}