gobsidian/internal/handlers/handlers.go

package handlers

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/gorilla/sessions"
	"github.com/h2non/filetype"

	"gobsidian/internal/config"
	"gobsidian/internal/markdown"
	"gobsidian/internal/models"
	"gobsidian/internal/utils"
)

type Handlers struct {
	config   *config.Config
	store    *sessions.CookieStore
	renderer *markdown.Renderer
}

func New(cfg *config.Config, store *sessions.CookieStore) *Handlers {
	return &Handlers{
		config:   cfg,
		store:    store,
		renderer: markdown.NewRenderer(cfg),
	}
}

func (h *Handlers) IndexHandler(c *gin.Context) {
	fmt.Printf("DEBUG: IndexHandler called\n")

	folderContents, err := utils.GetFolderContents("", h.config)
	if err != nil {
		fmt.Printf("DEBUG: Error getting folder contents: %v\n", err)
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to read directory",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	fmt.Printf("DEBUG: Found %d folder contents\n", len(folderContents))

	notesTree, err := utils.BuildTreeStructure(h.config.NotesDir, h.config.NotesDirHideSidepane, h.config)
	if err != nil {
		fmt.Printf("DEBUG: Error building tree structure: %v\n", err)
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to build tree structure",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	fmt.Printf("DEBUG: Tree structure built, app_name: %s\n", h.config.AppName)

	c.HTML(http.StatusOK, "folder", gin.H{
		"app_name":                 h.config.AppName,
		"folder_path":              "",
		"folder_contents":          folderContents,
		"notes_tree":               notesTree,
		"active_path":              []string{},
		"current_note":             nil,
		"breadcrumbs":              utils.GenerateBreadcrumbs(""),
		"allowed_image_extensions": h.config.AllowedImageExtensions,
		"allowed_file_extensions":  h.config.AllowedFileExtensions,
		"ContentTemplate":          "folder_content",
		"ScriptsTemplate":          "folder_scripts",
		"Page":                     "folder",
	})
}

func (h *Handlers) FolderHandler(c *gin.Context) {
	folderPath := strings.TrimPrefix(c.Param("path"), "/")

	// Security check - prevent path traversal
	if strings.Contains(folderPath, "..") {
		c.HTML(http.StatusBadRequest, "error", gin.H{
			"error":            "Invalid path",
			"app_name":         h.config.AppName,
			"message":          "Path traversal is not allowed",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	// Check if path is in skipped directories
	if utils.IsPathInSkippedDirs(folderPath, h.config.NotesDirSkip) {
		c.HTML(http.StatusForbidden, "error", gin.H{
			"error":            "Access denied",
			"app_name":         h.config.AppName,
			"message":          "This directory is not accessible",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	folderContents, err := utils.GetFolderContents(folderPath, h.config)
	if err != nil {
		c.HTML(http.StatusNotFound, "error", gin.H{
			"error":            "Folder not found",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	notesTree, err := utils.BuildTreeStructure(h.config.NotesDir, h.config.NotesDirHideSidepane, h.config)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to build tree structure",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	c.HTML(http.StatusOK, "folder", gin.H{
		"app_name":                 h.config.AppName,
		"folder_path":              folderPath,
		"folder_contents":          folderContents,
		"notes_tree":               notesTree,
		"active_path":              utils.GetActivePath(folderPath),
		"current_note":             nil,
		"breadcrumbs":              utils.GenerateBreadcrumbs(folderPath),
		"allowed_image_extensions": h.config.AllowedImageExtensions,
		"allowed_file_extensions":  h.config.AllowedFileExtensions,
		"ContentTemplate":          "folder_content",
		"ScriptsTemplate":          "folder_scripts",
		"Page":                     "folder",
	})
}

func (h *Handlers) NoteHandler(c *gin.Context) {
	notePath := strings.TrimPrefix(c.Param("path"), "/")

	if !strings.HasSuffix(notePath, ".md") {
		c.HTML(http.StatusBadRequest, "error", gin.H{
			"error":            "Invalid note path",
			"app_name":         h.config.AppName,
			"message":          "Note path must end with .md",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	// Security check
	if strings.Contains(notePath, "..") {
		c.HTML(http.StatusBadRequest, "error", gin.H{
			"error":            "Invalid path",
			"app_name":         h.config.AppName,
			"message":          "Path traversal is not allowed",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	// Check if path is in skipped directories
	if utils.IsPathInSkippedDirs(notePath, h.config.NotesDirSkip) {
		c.HTML(http.StatusForbidden, "error", gin.H{
			"error":            "Access denied",
			"app_name":         h.config.AppName,
			"message":          "This note is not accessible",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	fullPath := filepath.Join(h.config.NotesDir, notePath)

	if _, err := os.Stat(fullPath); os.IsNotExist(err) {
		c.HTML(http.StatusNotFound, "error", gin.H{
			"error":            "Note not found",
			"app_name":         h.config.AppName,
			"message":          "The requested note does not exist",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	content, err := os.ReadFile(fullPath)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to read note",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	htmlContent, err := h.renderer.RenderMarkdown(string(content), notePath)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to render markdown",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	notesTree, err := utils.BuildTreeStructure(h.config.NotesDir, h.config.NotesDirHideSidepane, h.config)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to build tree structure",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	title := strings.TrimSuffix(filepath.Base(notePath), ".md")
	folderPath := filepath.Dir(notePath)
	if folderPath == "." {
		folderPath = ""
	}

	c.HTML(http.StatusOK, "note", gin.H{
		"app_name":     h.config.AppName,
		"title":        title,
		"content":      htmlContent,
		"note_path":    notePath,
		"folder_path":  folderPath,
		"notes_tree":   notesTree,
		"active_path":  utils.GetActivePath(folderPath),
		"current_note": notePath,
		"breadcrumbs":  utils.GenerateBreadcrumbs(folderPath),
		"ContentTemplate": "note_content",
		"ScriptsTemplate": "note_scripts",
		"Page":            "note",
	})
}

func (h *Handlers) ServeAttachedImageHandler(c *gin.Context) {
	imagePath := strings.TrimPrefix(c.Param("path"), "/")

	// Security check
	if strings.Contains(imagePath, "..") {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	var fullPath string

	switch h.config.ImageStorageMode {
	case 1: // Root directory
		fullPath = filepath.Join(h.config.NotesDir, imagePath)
	case 3: // Same as note directory
		fullPath = filepath.Join(h.config.NotesDir, imagePath)
	case 4: // Subfolder of note directory
		fullPath = filepath.Join(h.config.NotesDir, imagePath)
	default:
		c.AbortWithStatus(http.StatusNotFound)
		return
	}

	// Check if file exists and is an image
	if _, err := os.Stat(fullPath); os.IsNotExist(err) {
		c.AbortWithStatus(http.StatusNotFound)
		return
	}

	if !models.IsImageFile(filepath.Base(imagePath), h.config.AllowedImageExtensions) {
		c.AbortWithStatus(http.StatusForbidden)
		return
	}

	c.File(fullPath)
}

func (h *Handlers) ServeStoredImageHandler(c *gin.Context) {
	filename := c.Param("filename")

	// Security check
	if strings.Contains(filename, "..") || strings.Contains(filename, "/") {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	if h.config.ImageStorageMode != 2 {
		c.AbortWithStatus(http.StatusNotFound)
		return
	}

	fullPath := filepath.Join(h.config.ImageStoragePath, filename)

	if _, err := os.Stat(fullPath); os.IsNotExist(err) {
		c.AbortWithStatus(http.StatusNotFound)
		return
	}

	if !models.IsImageFile(filename, h.config.AllowedImageExtensions) {
		c.AbortWithStatus(http.StatusForbidden)
		return
	}

	c.File(fullPath)
}

func (h *Handlers) DownloadHandler(c *gin.Context) {
	filePath := strings.TrimPrefix(c.Param("path"), "/")

	// Security check
	if strings.Contains(filePath, "..") {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	fullPath := filepath.Join(h.config.NotesDir, filePath)

	if _, err := os.Stat(fullPath); os.IsNotExist(err) {
		c.AbortWithStatus(http.StatusNotFound)
		return
	}

	filename := filepath.Base(filePath)
	c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", filename))
	c.File(fullPath)
}

func (h *Handlers) ViewTextHandler(c *gin.Context) {
	filePath := strings.TrimPrefix(c.Param("path"), "/")

	// Security check
	if strings.Contains(filePath, "..") {
		c.HTML(http.StatusBadRequest, "error", gin.H{
			"error":            "Invalid path",
			"app_name":         h.config.AppName,
			"message":          "Path traversal is not allowed",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	fullPath := filepath.Join(h.config.NotesDir, filePath)

	if _, err := os.Stat(fullPath); os.IsNotExist(err) {
		c.HTML(http.StatusNotFound, "error", gin.H{
			"error":            "File not found",
			"app_name":         h.config.AppName,
			"message":          "The requested file does not exist",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	// Check if file extension is allowed
	if !models.IsAllowedFile(filePath, h.config.AllowedFileExtensions) {
		c.HTML(http.StatusForbidden, "error", gin.H{
			"error":            "File type not allowed",
			"app_name":         h.config.AppName,
			"message":          "This file type cannot be viewed",
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	content, err := os.ReadFile(fullPath)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to read file",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	notesTree, err := utils.BuildTreeStructure(h.config.NotesDir, h.config.NotesDirHideSidepane, h.config)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error", gin.H{
			"error":            "Failed to build tree structure",
			"app_name":         h.config.AppName,
			"message":          err.Error(),
			"ContentTemplate":  "error_content",
			"ScriptsTemplate":  "error_scripts",
			"Page":             "error",
		})
		return
	}

	folderPath := filepath.Dir(filePath)
	if folderPath == "." {
		folderPath = ""
	}

	c.HTML(http.StatusOK, "view_text", gin.H{
		"app_name":    h.config.AppName,
		"file_name":   filepath.Base(filePath),
		"file_path":   filePath,
		"content":     string(content),
		"folder_path": folderPath,
		"notes_tree":  notesTree,
		"active_path": utils.GetActivePath(folderPath),
		"breadcrumbs": utils.GenerateBreadcrumbs(folderPath),
		"ContentTemplate": "view_text_content",
		"ScriptsTemplate": "view_text_scripts",
		"Page":            "view_text",
	})
}

func (h *Handlers) UploadHandler(c *gin.Context) {
	// Parse multipart form
	if err := c.Request.ParseMultipartForm(h.config.MaxContentLength); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "File too large or invalid form data"})
		return
	}

	// Get the upload path
	uploadPath := c.PostForm("path")
	if uploadPath == "" {
		uploadPath = ""
	}

	// Security check
	if strings.Contains(uploadPath, "..") {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid upload path"})
		return
	}

	file, header, err := c.Request.FormFile("file")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "No file uploaded"})
		return
	}
	defer file.Close()

	// Validate file type
	buffer := make([]byte, 512)
	if _, err := file.Read(buffer); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Failed to read file"})
		return
	}
	file.Seek(0, 0) // Reset file pointer

	kind, _ := filetype.Match(buffer)
	if kind == filetype.Unknown {
		// Allow text files and other allowed extensions
		if !models.IsAllowedFile(header.Filename, append(h.config.AllowedImageExtensions, h.config.AllowedFileExtensions...)) {
			c.JSON(http.StatusBadRequest, gin.H{"error": "File type not allowed"})
			return
		}
	} else {
		// Check if detected type is allowed
		isImageType := strings.HasPrefix(kind.MIME.Value, "image/")
		if !isImageType && !models.IsAllowedFile(header.Filename, h.config.AllowedFileExtensions) {
			c.JSON(http.StatusBadRequest, gin.H{"error": "File type not allowed"})
			return
		}
	}

	// Determine upload directory
	var uploadDir string
	isImage := models.IsImageFile(header.Filename, h.config.AllowedImageExtensions)

	if isImage {
		// For images, use the configured storage mode
		storageInfo := utils.GetImageStorageInfo(uploadPath, h.config)
		uploadDir = storageInfo.StorageDir
	} else {
		// For other files, upload to the current folder
		uploadDir = filepath.Join(h.config.NotesDir, uploadPath)
	}

	// Ensure upload directory exists
	if err := utils.EnsureDir(uploadDir); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create upload directory"})
		return
	}

	// Create destination file
	destPath := filepath.Join(uploadDir, header.Filename)
	dest, err := os.Create(destPath)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create destination file"})
		return
	}
	defer dest.Close()

	// Copy file content
	if _, err := io.Copy(dest, file); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to save file"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"success":  true,
		"message":  "File uploaded successfully",
		"filename": header.Filename,
		"size":     header.Size,
	})
}

func (h *Handlers) TreeAPIHandler(c *gin.Context) {
	notesTree, err := utils.BuildTreeStructure(h.config.NotesDir, h.config.NotesDirHideSidepane, h.config)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, notesTree)
}

// SearchHandler performs a simple full-text search across markdown and allowed text files
// within the notes directory, honoring skipped directories.
// GET /api/search?q=term
func (h *Handlers) SearchHandler(c *gin.Context) {
	query := strings.TrimSpace(c.Query("q"))
	if query == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "missing query"})
		return
	}

	// Case-insensitive search
	qLower := strings.ToLower(query)

	type Snippet struct {
		Line    int    `json:"line"`
		Preview string `json:"preview"`
	}
	type Result struct {
		Path     string    `json:"path"`
		Type     string    `json:"type"` // "md" or "text"
		Snippets []Snippet `json:"snippets"`
	}

	results := make([]Result, 0, 32)

	// Walk the notes directory
	err := filepath.Walk(h.config.NotesDir, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return nil // skip on error
		}
		if info.IsDir() {
			// Compute relative dir path to check skip list
			rel, _ := filepath.Rel(h.config.NotesDir, path)
			rel = filepath.ToSlash(rel)
			if rel == "." {
				rel = ""
			}
			if utils.IsPathInSkippedDirs(rel, h.config.NotesDirSkip) {
				return filepath.SkipDir
			}
			return nil
		}

		// Compute relative file path
		relPath, _ := filepath.Rel(h.config.NotesDir, path)
		relPath = filepath.ToSlash(relPath)

		// Skip disallowed files
		ext := strings.ToLower(filepath.Ext(relPath))
		isMD := ext == ".md"
		if !isMD && !models.IsAllowedFile(relPath, h.config.AllowedFileExtensions) {
			return nil
		}

		// Read file content (limit size to prevent huge memory usage)
		data, readErr := os.ReadFile(path)
		if readErr != nil {
			return nil
		}
		content := string(data)
		contentLower := strings.ToLower(content)
		if !strings.Contains(contentLower, qLower) {
			return nil
		}

		// Build snippets: show up to 3 matches with 2 lines of context
		lines := strings.Split(content, "\n")
		linesLower := strings.Split(contentLower, "\n")
		snippets := make([]Snippet, 0, 3)
		for i := 0; i < len(linesLower) && len(snippets) < 3; i++ {
			if strings.Contains(linesLower[i], qLower) {
				start := i - 2
				if start < 0 {
					start = 0
				}
				end := i + 2
				if end >= len(lines) {
					end = len(lines) - 1
				}
				// Join preview lines
				preview := strings.Join(lines[start:end+1], "\n")
				snippets = append(snippets, Snippet{Line: i + 1, Preview: preview})
			}
		}

		rtype := "text"
		if isMD {
			rtype = "md"
		}
		results = append(results, Result{Path: relPath, Type: rtype, Snippets: snippets})
		return nil
	})

	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"query": query, "results": results})
}