//! Maps a package's configured `source` to the endpoints the pipeline
//! stages talk to. The only module that knows how each hosting service
//! lays out its URLs; `checker` and `fetcher` take what it hands them.

use crate::config::{Package, Source};
use crate::github::GithubEndpoints;
use anyhow::{Context, Result};

#[derive(Debug, Clone)]
pub enum Endpoints {
    Github(GithubEndpoints),
    /// A Forgejo/Gitea instance's API root, i.e. `<base_url>/api/v1`.
    Forgejo {
        api: String,
    },
}

impl Endpoints {
    /// Errors only if a `forgejo-release` package has no `base_url`, which
    /// `config::load_packages_dir` already rejects — this is the same check
    /// again for a `Package` built some other way, not a second source of
    /// truth.
    pub fn for_package(pkg: &Package) -> Result<Self> {
        match pkg.source {
            Source::GithubRelease => Ok(Endpoints::Github(GithubEndpoints::default())),
            Source::ForgejoRelease => {
                let base_url = pkg
                    .base_url
                    .as_deref()
                    .context("source = \"forgejo-release\" needs a base_url")?;
                Ok(Endpoints::Forgejo {
                    api: format!("{}/api/v1", base_url.trim_end_matches('/')),
                })
            }
        }
    }

    /// The releases API root. GitHub and Forgejo both serve
    /// `/repos/{owner}/{repo}/releases/tags/{tag}` under it with the same
    /// `assets[].{name, browser_download_url}` shape, which is why
    /// `fetcher` and `verifier` need only this and not the enum.
    pub fn api(&self) -> &str {
        match self {
            Endpoints::Github(github) => &github.api,
            Endpoints::Forgejo { api } => api,
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    fn package(extra: &str) -> Package {
        toml::from_str(&format!(
            r#"
            repo = "o/r"
            asset_pattern = "x"
            {extra}
            [verification]
            method = "same-origin-sha256"
            checksum_asset_pattern = "SUMS"
            "#
        ))
        .unwrap()
    }

    #[test]
    fn github_source_uses_real_github() {
        let endpoints = Endpoints::for_package(&package("")).unwrap();
        assert_eq!(endpoints.api(), "https://api.github.com");
        assert!(matches!(endpoints, Endpoints::Github(_)));
    }

    #[test]
    fn forgejo_source_appends_api_v1() {
        let pkg = package("source = \"forgejo-release\"\nbase_url = \"https://code.example.com\"");
        let endpoints = Endpoints::for_package(&pkg).unwrap();
        assert_eq!(endpoints.api(), "https://code.example.com/api/v1");
    }

    #[test]
    fn forgejo_source_tolerates_trailing_slash() {
        let pkg = package("source = \"forgejo-release\"\nbase_url = \"https://code.example.com/\"");
        let endpoints = Endpoints::for_package(&pkg).unwrap();
        assert_eq!(endpoints.api(), "https://code.example.com/api/v1");
    }

    #[test]
    fn forgejo_source_without_base_url_errors() {
        let err = Endpoints::for_package(&package("source = \"forgejo-release\"")).unwrap_err();
        assert!(err.to_string().contains("needs a base_url"));
    }
}