//! `dependency <number> [list|add|remove] [numbers...]` — manage an
//! issue/PR's "blocked by" dependency links. Default action: list.
//!
//! Forgejo's dependency endpoints work on the shared issue/PR index (a
//! PR is an issue internally), so this is wired into both `issue <verb>`
//! and `pr <verb>` the same way `labels`/`assign`/`timeline` are.
//! Setting `<number>`'s dependency on `<dep>` means `<number>` is
//! blocked by `<dep>` — matching the forge web UI's "add dependency"
//! action, which is a same-repo-only relationship (there is no
//! cross-repo dependency support in this CLI, mirroring the UI).

use anyhow::{Result, bail};
use clap::{Args as ClapArgs, Subcommand};
use forgejo_api::structs::IssueMeta;

use crate::client::{Client, index};
use crate::verbs::{dependency_summaries, print_json};

#[derive(ClapArgs)]
pub struct Args {
    /// Issue or PR number.
    pub(crate) number: u64,
    #[command(subcommand)]
    action: Option<Action>,
}

#[derive(Subcommand)]
enum Action {
    /// List dependencies (default when no action is given) — the
    /// issues/PRs this one is blocked by.
    List,
    /// Add one or more issues/PRs this one is blocked by.
    Add {
        /// Issue/PR numbers to add as dependencies.
        deps: Vec<u64>,
    },
    /// Remove one or more dependency links.
    Remove {
        /// Issue/PR numbers to remove as dependencies.
        deps: Vec<u64>,
    },
}

pub fn run(client: &Client, args: Args) -> Result<()> {
    let (owner, name) = client.owner_repo()?;
    let idx = index(args.number)?;
    match args.action.unwrap_or(Action::List) {
        Action::List => {}
        Action::Add { deps } => {
            if deps.is_empty() {
                bail!("hive-forge dependency add: pass at least one issue/PR number");
            }
            for dep in &deps {
                client
                    .api()
                    .issue_create_issue_dependencies(owner, name, idx, dep_meta(owner, name, *dep)?)
                    .send()?;
            }
        }
        Action::Remove { deps } => {
            if deps.is_empty() {
                bail!("hive-forge dependency remove: pass at least one issue/PR number");
            }
            for dep in &deps {
                client
                    .api()
                    .issue_remove_issue_dependencies(owner, name, idx, dep_meta(owner, name, *dep)?)
                    .send()?;
            }
        }
    }
    let deps = dependency_summaries(client, owner, name, args.number)?;
    print_json(&serde_json::json!(deps))
}

/// Build the `IssueMeta` body the create/remove endpoints want.
///
/// `owner`/`repo` are filled in with the *same* repo the request URL
/// already targets — not left `None`. Forgejo's dependency handler
/// resolves the dependency's repo from these body fields rather than
/// defaulting an absent value to the URL's own owner/repo, so omitting
/// them 404s looking up an empty-string repo (`owner/repo: not found`
/// — measured, not guessed: `hive-forge dependency <n> add <dep>`
/// failed this way for every same-repo pair before this fix). This CLI
/// still only supports same-repo dependencies (matching the forge web
/// UI) — the fields are populated, not opened up to cross-repo.
fn dep_meta(owner: &str, repo: &str, dep: u64) -> Result<IssueMeta> {
    Ok(IssueMeta {
        index: Some(index(dep)?),
        owner: Some(owner.to_owned()),
        repo: Some(repo.to_owned()),
    })
}