rootle 0.2.2

//! GitHub provider (reference implementation, plans/0005): wraps the
//! REST `Client` — auth resolution, sha-keyed disk cache, ETag
//! revalidation all live inside it (PLAN.md §7/§8).

use super::{Capabilities, CodeMatch, Provider, SearchItem, TreeNode, TreeResult};
use crate::github::Client;

pub struct GitHubProvider {
    client: Client,
}

impl GitHubProvider {
    pub fn new(max_mb: u64) -> Self {
        // Self-hardening: orphan sweep + LRU eviction of the content
        // store, off-thread — the TUI never knows this exists.
        let max_bytes = max_mb * 1024 * 1024;
        std::thread::spawn(move || crate::github::cache::harden(max_bytes));
        GitHubProvider {
            client: Client::new(),
        }
    }

    /// Token-less provider (tests, offline defaults).
    /// Token-less, no hardening (tests and offline defaults).
    pub fn anonymous() -> Self {
        GitHubProvider {
            client: Client::anonymous(),
        }
    }
}

fn split_repo(repo: &str) -> Result<(&str, &str), String> {
    repo.split_once('/')
        .ok_or_else(|| format!("bad repo id: {repo:?} (expected owner/name)"))
}

impl From<&crate::github::types::TreeEntry> for TreeNode {
    fn from(e: &crate::github::types::TreeEntry) -> Self {
        TreeNode {
            path: e.path.clone(),
            is_dir: e.kind == "tree",
            sha: e.sha.clone(),
            size: e.size,
        }
    }
}

impl Provider for GitHubProvider {
    fn name(&self) -> &str {
        "github"
    }

    fn capabilities(&self) -> Capabilities {
        Capabilities {
            orgs: true,
            code_search: true,
        }
    }

    fn default_orgs(&self) -> Vec<String> {
        ["ratatui", "tokio-rs", "helix-editor"]
            .iter()
            .map(|s| s.to_string())
            .collect()
    }

    fn search(&self, query: &str) -> Result<Vec<SearchItem>, String> {
        self.client.search(query)
    }

    fn org_repos(&self, org: &str) -> Result<Vec<String>, String> {
        self.client.org_repos(org)
    }

    fn fetch_tree(&self, repo: &str) -> Result<TreeResult, String> {
        let (owner, name) = split_repo(repo)?;
        let (tree, truncated, branch) = self.client.fetch_tree(owner, name)?;
        Ok(TreeResult {
            entries: tree.tree.iter().map(Into::into).collect(),
            truncated,
            branch,
        })
    }

    fn fetch_blob(&self, repo: &str, sha: &str) -> Result<Vec<u8>, String> {
        let (owner, name) = split_repo(repo)?;
        self.client.fetch_blob(owner, name, sha)
    }

    fn clone_url(&self, repo: &str) -> Result<String, String> {
        split_repo(repo)?;
        Ok(format!("https://github.com/{repo}.git"))
    }

    fn web_url(
        &self,
        repo: &str,
        path: &str,
        branch: &str,
        line: Option<u32>,
        is_file: bool,
    ) -> Result<String, String> {
        split_repo(repo)?;
        if path.is_empty() {
            return Ok(format!("https://github.com/{repo}"));
        }
        // Blob vs tree grammar; the branch is cheap to resolve — the
        // tree is disk-cached whenever the repo has been browsed.
        let branch = if branch.is_empty() {
            self.fetch_tree(repo).map(|t| t.branch)?
        } else {
            branch.to_string()
        };
        let kind = if is_file { "blob" } else { "tree" };
        let fragment = match (is_file, line) {
            (true, Some(line)) => format!("#L{line}"),
            _ => String::new(),
        };
        Ok(format!(
            "https://github.com/{repo}/{kind}/{branch}/{path}{fragment}"
        ))
    }

    fn org_url(&self, org: &str) -> Result<String, String> {
        Ok(format!("https://github.com/{org}"))
    }

    fn search_code(&self, q: &str) -> Result<Vec<CodeMatch>, String> {
        let items = self.client.search_code(q)?;
        Ok(items
            .into_iter()
            .map(|item| CodeMatch {
                repo: item.repository.full_name,
                path: item.path,
                sha: item.sha,
                branch: item
                    .repository
                    .default_branch
                    .unwrap_or_else(|| "main".into()),
                matches: item
                    .text_matches
                    .iter()
                    .flat_map(|tm| tm.matches.iter().map(|m| m.text.clone()))
                    .collect(),
            })
            .collect())
    }
}

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

    #[test]
    fn web_url_grammar() {
        let p = GitHubProvider::anonymous();
        // Repo root.
        assert_eq!(
            p.web_url("ratatui/ratatui", "", "", None, false).unwrap(),
            "https://github.com/ratatui/ratatui"
        );
        // File with a line: blob + fragment (known branch, no I/O).
        assert_eq!(
            p.web_url("ratatui/ratatui", "src/lib.rs", "main", Some(42), true)
                .unwrap(),
            "https://github.com/ratatui/ratatui/blob/main/src/lib.rs#L42"
        );
        // File without a line: blob, no fragment.
        assert_eq!(
            p.web_url("ratatui/ratatui", "src/lib.rs", "main", None, true)
                .unwrap(),
            "https://github.com/ratatui/ratatui/blob/main/src/lib.rs"
        );
        // Directory: tree.
        assert_eq!(
            p.web_url("ratatui/ratatui", "src", "master", None, false)
                .unwrap(),
            "https://github.com/ratatui/ratatui/tree/master/src"
        );
        assert_eq!(p.org_url("ratatui").unwrap(), "https://github.com/ratatui");
    }

    #[test]
    fn clone_url_grammar() {
        let p = GitHubProvider::anonymous();
        assert_eq!(
            p.clone_url("ratatui/ratatui").unwrap(),
            "https://github.com/ratatui/ratatui.git"
        );
        assert!(p.clone_url("no-slash").is_err());
    }
}