use async_trait::async_trait;
use bytes::Bytes;
use domain::errors::DomainError;
use domain::ports::{FileEntry, FileStoragePort};
use std::path::PathBuf;

pub struct LocalFileStorage {
    base_path: PathBuf,
}

impl LocalFileStorage {
    pub fn new(base_path: impl Into<PathBuf>) -> Self {
        Self {
            base_path: base_path.into(),
        }
    }

    fn resolve(&self, path: &str) -> Result<PathBuf, DomainError> {
        let full = self.base_path.join(path);
        // Prevent path traversal
        if !full.starts_with(&self.base_path) {
            return Err(DomainError::Validation(
                "Path traversal not allowed".to_string(),
            ));
        }
        Ok(full)
    }
}

#[async_trait]
impl FileStoragePort for LocalFileStorage {
    async fn store_file(&self, path: &str, data: Bytes) -> Result<(), DomainError> {
        let full = self.resolve(path)?;
        if let Some(parent) = full.parent() {
            tokio::fs::create_dir_all(parent)
                .await
                .map_err(|e| DomainError::Internal(format!("Failed to create dirs: {e}")))?;
        }
        tokio::fs::write(&full, &data)
            .await
            .map_err(|e| DomainError::Internal(format!("Failed to write file: {e}")))?;
        Ok(())
    }

    async fn read_file(&self, path: &str) -> Result<Bytes, DomainError> {
        let full = self.resolve(path)?;
        let data = tokio::fs::read(&full).await.map_err(|e| match e.kind() {
            std::io::ErrorKind::NotFound => DomainError::NotFound(path.to_string()),
            _ => DomainError::Internal(format!("Failed to read file: {e}")),
        })?;
        Ok(Bytes::from(data))
    }

    async fn delete_file(&self, path: &str) -> Result<(), DomainError> {
        let full = self.resolve(path)?;
        match tokio::fs::remove_file(&full).await {
            Ok(()) => Ok(()),
            Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(()),
            Err(e) => Err(DomainError::Internal(format!("Failed to delete file: {e}"))),
        }
    }

    async fn list_directory(&self, path: &str) -> Result<Vec<FileEntry>, DomainError> {
        let full = self.resolve(path)?;
        let mut entries = Vec::new();
        let mut read_dir = tokio::fs::read_dir(&full)
            .await
            .map_err(|e| match e.kind() {
                std::io::ErrorKind::NotFound => DomainError::NotFound(path.to_string()),
                _ => DomainError::Internal(format!("Failed to read dir: {e}")),
            })?;
        while let Some(entry) = read_dir
            .next_entry()
            .await
            .map_err(|e| DomainError::Internal(e.to_string()))?
        {
            let meta = entry
                .metadata()
                .await
                .map_err(|e| DomainError::Internal(e.to_string()))?;
            entries.push(FileEntry {
                path: entry.file_name().to_string_lossy().to_string(),
                size_bytes: meta.len(),
                is_directory: meta.is_dir(),
            });
        }
        Ok(entries)
    }

    async fn file_exists(&self, path: &str) -> Result<bool, DomainError> {
        let full = self.resolve(path)?;
        Ok(full.exists())
    }

    async fn available_space(&self) -> Result<u64, DomainError> {
        // Simple stub: return a large number
        Ok(u64::MAX)
    }
}