//! Text search tools: Grep (line matching) and Glob (filename pattern matching).

use crate::tools::{resolve_path, Tool, ToolCtx};
use anyhow::Result;
use globset::{GlobBuilder, GlobSetBuilder};
use ignore::Walk;
use serde_json::{json, Value};
use std::fs;

pub struct Grep;

impl Tool for Grep {
    fn name(&self) -> &'static str {
        "grep"
    }

    fn description(&self) -> &'static str {
        "Search for a pattern in files using recursive text search"
    }

    fn parameters(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "pattern": {
                    "type": "string",
                    "description": "Text pattern to search for"
                },
                "path": {
                    "type": "string",
                    "description": "Path to search in (relative to workspace root)"
                }
            },
            "required": ["pattern", "path"]
        })
    }

    fn run(&self, ctx: &ToolCtx, args: &Value) -> Result<String> {
        let pattern = crate::tools::arg_str(args, "pattern")?;
        let rel = crate::tools::arg_str(args, "path")?;
        let path = resolve_path(&ctx.workspaces, &rel)?;

        if !path.exists() {
            anyhow::bail!("path '{rel}' does not exist");
        }
        if !path.is_dir() {
            anyhow::bail!("path '{rel}' is not a directory");
        }

        let mut results: Vec<(String, usize, String)> = Vec::new();
        for entry in Walk::new(&path).flatten() {
            let file_path = entry.path();
            if !file_path.is_file() {
                continue;
            }
            if let Ok(content) = fs::read_to_string(file_path) {
                for (i, line) in content.lines().enumerate() {
                    if line.contains(&pattern) {
                        let rel_path = file_path
                            .strip_prefix(&path)
                            .unwrap_or(file_path)
                            .display()
                            .to_string();
                        results.push((rel_path, i + 1, line.to_string()));
                    }
                }
            }
        }

        if results.is_empty() {
            return Ok(format!("no matches found for '{pattern}' in {rel}"));
        }
        let output = results
            .iter()
            .map(|(f, line, text)| format!("{f}:{line}:{text}"))
            .collect::<Vec<_>>()
            .join("\n");
        Ok(format!("found {} matches:\n{}", results.len(), output))
    }
}

pub struct Glob;

impl Tool for Glob {
    fn name(&self) -> &'static str {
        "glob"
    }

    fn description(&self) -> &'static str {
        "List files matching a glob pattern"
    }

    fn parameters(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "pattern": {
                    "type": "string",
                    "description": "Glob pattern to match files (e.g. '**/*.rs')"
                },
                "path": {
                    "type": "string",
                    "description": "Root path to search from (relative to workspace root)"
                }
            },
            "required": ["pattern", "path"]
        })
    }

    fn run(&self, ctx: &ToolCtx, args: &Value) -> Result<String> {
        let pat_str = crate::tools::arg_str(args, "pattern")?;
        let rel = crate::tools::arg_str(args, "path")?;
        let root = resolve_path(&ctx.workspaces, &rel)?;

        if !root.exists() || !root.is_dir() {
            anyhow::bail!("path '{rel}' is not a valid directory");
        }

        let mut builder = GlobSetBuilder::new();
        let full_pattern = root.join(&pat_str).display().to_string();
        builder.add(
            GlobBuilder::new(&full_pattern)
                .build()
                .map_err(|e| anyhow::anyhow!("invalid glob pattern '{pat_str}': {e}"))?,
        );
        let glob_set = builder.build()?;

        let mut matches: Vec<String> = Vec::new();
        for entry in Walk::new(&root).flatten() {
            let p = entry.path();
            if glob_set.is_match(p) {
                let rel_path = p.strip_prefix(&root).unwrap_or(p).display().to_string();
                matches.push(format!(
                    "{}{}",
                    rel_path,
                    if p.is_dir() { "/" } else { "" }
                ));
            }
        }
        matches.sort();
        if matches.is_empty() {
            return Ok(format!("no files match '{pat_str}' in {rel}"));
        }
        Ok(matches.join("\n"))
    }
}