//! Commenting on an agent's config PRs as the core forge user — how a hive
//! reports a merged config commit it refused to deploy back onto the PR that
//! merged it. Finding that PR only reads, so it uses [`reader_token`].

use anyhow::{Context, Result};

use super::{CONFIG_ORG, api, bounded, core_token, reader_token};

/// Full `owner/name` path of an agent's config repo on the forge.
pub fn config_repo(agent: &str) -> String {
    format!("{CONFIG_ORG}/{agent}")
}

/// The number of the merged PR that put commit `sha` on `repo`'s base branch.
///
/// # Errors
/// No read token, malformed repo, no such PR, or transport/API failure.
pub async fn merged_pr_for_commit(repo: &str, sha: &str) -> Result<u64> {
    let reader = reader_token().await.context("no forge read token")?;
    let (owner, name) = repo
        .split_once('/')
        .with_context(|| format!("forge repo `{repo}` is not owner/name"))?;
    let pull = bounded(
        "GET pull request of commit",
        api(reader.value())?.repo_get_commit_pull_request(owner, name, sha),
    )
    .await?
    .context("GET pull request of commit")?;
    pull.number
        .and_then(|n| u64::try_from(n).ok())
        .with_context(|| format!("pull request of {sha} in {repo} carries no number"))
}

/// Post a comment to PR (= issue) `pr` on `repo` as the core forge user.
/// PRs are issues in Forgejo, so the PR number is the issue index.
///
/// # Errors
/// Absent core token, malformed repo, or transport/API failure.
pub async fn post_pr_comment(repo: &str, pr: u64, body: &str) -> Result<()> {
    let token = core_token().context("forge core token absent")?;
    let (owner, name) = repo
        .split_once('/')
        .with_context(|| format!("forge repo `{repo}` is not owner/name"))?;
    let index = i64::try_from(pr).with_context(|| format!("PR index {pr} overflows i64"))?;
    bounded(
        "post PR comment",
        api(&token)?.issue_create_comment(
            owner,
            name,
            index,
            forgejo_api::structs::CreateIssueCommentOption {
                body: body.to_owned(),
                updated_at: None,
            },
        ),
    )
    .await?
    .context("post PR comment")?;
    Ok(())
}