package storage

import (
	"bytes"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
)

func TestLocalStorage(t *testing.T) {
	// Create temporary directory for testing
	tmpDir := t.TempDir()
	
	config := LocalConfig{
		RootDir: tmpDir,
		BaseURL: "http://localhost:8080/files",
	}
	
	storage, err := NewLocalStorage(config)
	assert.NoError(t, err)
	assert.NotNil(t, storage)
	
	t.Run("Store and Retrieve File", func(t *testing.T) {
		content := []byte("test file content")
		reader := bytes.NewReader(content)
		
		// Store file
		path, err := storage.Store("test.txt", reader, "text/plain")
		assert.NoError(t, err)
		assert.NotEmpty(t, path)
		
		// Verify file exists
		exists, err := storage.Exists(path)
		assert.NoError(t, err)
		assert.True(t, exists)
		
		// Retrieve file
		retrievedReader, err := storage.Retrieve(path)
		assert.NoError(t, err)
		defer retrievedReader.Close()
		
		retrievedContent, err := io.ReadAll(retrievedReader)
		assert.NoError(t, err)
		assert.Equal(t, content, retrievedContent)
	})
	
	t.Run("Get File Metadata", func(t *testing.T) {
		content := []byte("metadata test content")
		reader := bytes.NewReader(content)
		
		path, err := storage.Store("metadata.txt", reader, "text/plain")
		assert.NoError(t, err)
		
		metadata, err := storage.GetMetadata(path)
		assert.NoError(t, err)
		assert.Equal(t, int64(len(content)), metadata.Size)
		assert.False(t, metadata.LastModified.IsZero())
	})
	
	t.Run("Get File URL", func(t *testing.T) {
		content := []byte("url test content")
		reader := bytes.NewReader(content)
		
		path, err := storage.Store("url.txt", reader, "text/plain")
		assert.NoError(t, err)
		
		url, err := storage.GetURL(path, time.Hour)
		assert.NoError(t, err)
		assert.Contains(t, url, path)
		assert.Contains(t, url, config.BaseURL)
	})
	
	t.Run("Delete File", func(t *testing.T) {
		content := []byte("delete test content")
		reader := bytes.NewReader(content)
		
		path, err := storage.Store("delete.txt", reader, "text/plain")
		assert.NoError(t, err)
		
		// Verify file exists
		exists, err := storage.Exists(path)
		assert.NoError(t, err)
		assert.True(t, exists)
		
		// Delete file
		err = storage.Delete(path)
		assert.NoError(t, err)
		
		// Verify file no longer exists
		exists, err = storage.Exists(path)
		assert.NoError(t, err)
		assert.False(t, exists)
	})
	
	t.Run("Path Validation", func(t *testing.T) {
		// Test directory traversal prevention
		_, err := storage.Retrieve("../../../etc/passwd")
		assert.Error(t, err)
		assert.IsType(t, &InvalidPathError{}, err)
		
		// Test absolute path rejection
		_, err = storage.Retrieve("/etc/passwd")
		assert.Error(t, err)
		assert.IsType(t, &InvalidPathError{}, err)
	})
	
	t.Run("File Not Found", func(t *testing.T) {
		_, err := storage.Retrieve("nonexistent.txt")
		assert.Error(t, err)
		assert.IsType(t, &FileNotFoundError{}, err)
		
		_, err = storage.GetMetadata("nonexistent.txt")
		assert.Error(t, err)
		assert.IsType(t, &FileNotFoundError{}, err)
		
		_, err = storage.GetURL("nonexistent.txt", time.Hour)
		assert.Error(t, err)
		assert.IsType(t, &FileNotFoundError{}, err)
	})
	
	t.Run("Storage Path Generation", func(t *testing.T) {
		content := []byte("path test content")
		reader1 := bytes.NewReader(content)
		reader2 := bytes.NewReader(content)
		
		// Store two files with same name
		path1, err := storage.Store("same.txt", reader1, "text/plain")
		assert.NoError(t, err)
		
		path2, err := storage.Store("same.txt", reader2, "text/plain")
		assert.NoError(t, err)
		
		// Paths should be different (unique)
		assert.NotEqual(t, path1, path2)
		
		// Both should exist
		exists1, err := storage.Exists(path1)
		assert.NoError(t, err)
		assert.True(t, exists1)
		
		exists2, err := storage.Exists(path2)
		assert.NoError(t, err)
		assert.True(t, exists2)
		
		// Both should have correct extension
		assert.True(t, strings.HasSuffix(path1, ".txt"))
		assert.True(t, strings.HasSuffix(path2, ".txt"))
		
		// Should be organized by date
		now := time.Now()
		expectedPrefix := filepath.Join(
			fmt.Sprintf("%04d", now.Year()),
			fmt.Sprintf("%02d", now.Month()),
			fmt.Sprintf("%02d", now.Day()),
		)
		assert.True(t, strings.HasPrefix(path1, expectedPrefix))
		assert.True(t, strings.HasPrefix(path2, expectedPrefix))
	})
}

func TestLocalStorageConfig(t *testing.T) {
	t.Run("Default Root Directory", func(t *testing.T) {
		config := LocalConfig{} // Empty config
		
		storage, err := NewLocalStorage(config)
		assert.NoError(t, err)
		assert.NotNil(t, storage)
		
		// Should create default uploads directory
		assert.Equal(t, "./uploads", storage.rootDir)
		
		// Verify directory was created
		_, err = os.Stat("./uploads")
		assert.NoError(t, err)
		
		// Clean up
		os.RemoveAll("./uploads")
	})
	
	t.Run("Custom Root Directory", func(t *testing.T) {
		tmpDir := t.TempDir()
		customDir := filepath.Join(tmpDir, "custom", "storage")
		
		config := LocalConfig{
			RootDir: customDir,
		}
		
		storage, err := NewLocalStorage(config)
		assert.NoError(t, err)
		assert.Equal(t, customDir, storage.rootDir)
		
		// Verify custom directory was created
		_, err = os.Stat(customDir)
		assert.NoError(t, err)
	})
}