dirge-agent 0.11.0

use std::path::Path;

use ignore::WalkBuilder;
use rig::completion::ToolDefinition;
use rig::tool::Tool;

use crate::agent::agent_loop::tool_input_repair::with_contract_hint;
use crate::agent::tools::cache::ToolCache;
use crate::agent::tools::{
    AskSender, ListDirArgs, PermCheck, ToolError, check_perm_path, is_skip_dir,
};

fn format_size(bytes: u64) -> String {
    const UNITS: &[&str] = &["B", "KB", "MB", "GB"];
    let mut size = bytes as f64;
    let mut unit_idx = 0;
    while size >= 1024.0 && unit_idx < UNITS.len() - 1 {
        size /= 1024.0;
        unit_idx += 1;
    }
    if unit_idx == 0 {
        format!("{} {}", bytes, UNITS[unit_idx])
    } else {
        format!("{:.1} {}", size, UNITS[unit_idx])
    }
}

fn count_dir_entries(path: &Path) -> u64 {
    std::fs::read_dir(path)
        .map(|rd| rd.count() as u64)
        .unwrap_or(0)
}

pub struct ListDirTool {
    pub permission: Option<PermCheck>,
    pub ask_tx: Option<AskSender>,
    pub cache: Option<ToolCache>,
}

impl ListDirTool {
    #[allow(dead_code)]
    pub fn new(permission: Option<PermCheck>, ask_tx: Option<AskSender>) -> Self {
        ListDirTool {
            permission,
            ask_tx,
            cache: None,
        }
    }

    pub fn with_cache(
        permission: Option<PermCheck>,
        ask_tx: Option<AskSender>,
        cache: ToolCache,
    ) -> Self {
        ListDirTool {
            permission,
            ask_tx,
            cache: Some(cache),
        }
    }
}

impl Tool for ListDirTool {
    const NAME: &'static str = "list_dir";

    type Error = ToolError;
    type Args = ListDirArgs;
    type Output = String;

    async fn definition(&self, _prompt: String) -> ToolDefinition {
        ToolDefinition {
            name: "list_dir".to_string(),
            description: with_contract_hint(
                "list_dir",
                "List the immediate files and directories in ONE directory (non-recursive). Shows type, size, and subdirectory entry counts; sorted directories-first then alphabetically. Respects .gitignore. Use `repo_overview` for a whole-project tree, `glob`/`find_files` to locate files by pattern, and `grep` to search contents.",
            ),
            parameters: serde_json::json!({
                "type": "object",
                "properties": {
                    "path": {
                        "type": "string",
                        "description": "Directory path (defaults to current working directory)"
                    },
                    "include_hidden": {
                        "type": "boolean",
                        "description": "Include dotfiles (.env, .gitignore, etc.) in the listing. Default false to avoid surfacing secrets and config files."
                    }
                },
                "required": []
            }),
        }
    }

    async fn call(&self, args: ListDirArgs) -> Result<String, ToolError> {
        let path = args.path.as_deref().unwrap_or(".");
        check_perm_path(&self.permission, &self.ask_tx, "list_dir", path).await?;

        // LOOP-3: dir stamp invalidates the cache on external mtime changes.
        let stamp = crate::agent::tools::cache::fs_stamp_or_cwd(path);
        let cache_key = format!("list_dir:{}:hidden={}:{}", path, args.include_hidden, stamp,);

        if let Some(ref cache) = self.cache
            && let Some(cached) = cache.get(&cache_key)
        {
            return Ok(cached);
        }

        let walker = WalkBuilder::new(path)
            .git_ignore(true)
            .git_global(true)
            .git_exclude(true)
            .require_git(false)
            // Hide dotfiles by default to avoid leaking .env etc.
            // into LLM context. See `FindFilesArgs::include_hidden`.
            .hidden(!args.include_hidden)
            .max_depth(Some(1))
            .filter_entry(|entry| {
                if entry.file_type().map(|t| t.is_dir()).unwrap_or(false) {
                    !is_skip_dir(entry.file_name().to_str().unwrap_or(""))
                } else {
                    true
                }
            })
            .build();

        // Cap on entries to keep the response from blowing context
        // when an agent points list_dir at something like
        // `~/node_modules` with `include_hidden=true`. Mirrors the
        // caps used by `grep` (`MAX_GREP_RESULTS`) and `find_files`
        // (`MAX_FIND_RESULTS`). Continue walking past the cap so the
        // footer can report a useful "...and N more" count rather
        // than truncating silently.
        const MAX_LIST_DIR_RESULTS: usize = 200;
        const COUNT_CEILING_MULTIPLIER: usize = 10;
        let count_ceiling = MAX_LIST_DIR_RESULTS.saturating_mul(COUNT_CEILING_MULTIPLIER);

        let mut entries: Vec<(String, String, String)> = Vec::new();
        let mut total_entries: usize = 0;
        let mut truncated_count = false;

        for result in walker {
            let entry = match result {
                Ok(e) => e,
                Err(_) => continue,
            };

            let name = entry.file_name().to_string_lossy().to_string();

            if entry.depth() == 0 {
                continue;
            }

            let meta = match entry.metadata() {
                Ok(m) => m,
                Err(_) => continue,
            };

            total_entries += 1;

            if entries.len() < MAX_LIST_DIR_RESULTS {
                let kind = if meta.is_dir() {
                    let count = count_dir_entries(entry.path());
                    format!("dir({})", count)
                } else if meta.is_symlink() {
                    "link".to_string()
                } else {
                    "file".to_string()
                };

                let size = if meta.is_file() {
                    format_size(meta.len())
                } else {
                    String::new()
                };

                entries.push((name, kind, size));
            }

            if total_entries >= count_ceiling {
                truncated_count = true;
                break;
            }
        }

        entries.sort_by(|a, b| {
            let a_is_dir = a.1.starts_with("dir") || a.1 == "link";
            let b_is_dir = b.1.starts_with("dir") || b.1 == "link";
            if a_is_dir != b_is_dir {
                b_is_dir.cmp(&a_is_dir)
            } else {
                a.0.cmp(&b.0)
            }
        });

        if entries.is_empty() {
            // Path is in the chamber banner; no need to repeat it.
            return Ok("(empty directory)".to_string());
        }

        // Summary line for at-a-glance counts: useful when the
        // listing is long enough to be truncated by
        // `tool_result_max_chars` — the LLM sees the totals even
        // if the per-entry rows get cut. The `dir(N)` markers
        // already show nested counts per directory.
        let dir_count = entries
            .iter()
            .filter(|(_, k, _)| k.starts_with("dir"))
            .count();
        let link_count = entries.iter().filter(|(_, k, _)| k == "link").count();
        let file_count = entries.len() - dir_count - link_count;

        let max_name = entries.iter().map(|e| e.0.len()).max().unwrap_or(0);
        // Summary counts reflect what's actually IN `entries`
        // (the displayed slice). The total is reported separately
        // when the cap fired.
        let mut summary = format!(
            "{} entries ({} dirs, {} files",
            entries.len(),
            dir_count,
            file_count,
        );
        if link_count > 0 {
            summary.push_str(&format!(", {link_count} symlinks"));
        }
        if total_entries > entries.len() {
            let total_label = if truncated_count {
                format!("{}+", total_entries)
            } else {
                total_entries.to_string()
            };
            let hidden = total_entries.saturating_sub(entries.len());
            let hidden_label = if truncated_count {
                format!("{}+", hidden)
            } else {
                hidden.to_string()
            };
            summary.push_str(&format!(
                "; showing {} of {}; {} more not shown",
                entries.len(),
                total_label,
                hidden_label,
            ));
        }
        summary.push_str("):\n");
        let mut result = summary;
        for (name, kind, size) in &entries {
            let padded = format!("{:width$}", name, width = max_name);
            let size_str = if size.is_empty() {
                String::new()
            } else {
                format!("  {}", size)
            };
            result.push_str(&format!("  [{}]  {}{}\n", kind, padded, size_str));
        }

        if let Some(ref cache) = self.cache {
            cache.set(&cache_key, result.clone());
        }

        Ok(result)
    }
}