feat: Refactor of Go backend code

app_mail.go

@@ -0,0 +1,88 @@
+// Package main provides email reading functionality for EMLy.
+// This file contains methods for reading EML, MSG, and PEC email files.
+package main
+
+import (
+	"emly/backend/utils/mail"
+)
+
+// =============================================================================
+// Email Reading Methods
+// =============================================================================
+
+// ReadEML reads a standard .eml file and returns the parsed email data.
+// EML files are MIME-formatted email messages commonly exported from email clients.
+//
+// Parameters:
+//   - filePath: Absolute path to the .eml file
+//
+// Returns:
+//   - *internal.EmailData: Parsed email with headers, body, and attachments
+//   - error: Any parsing errors
+func (a *App) ReadEML(filePath string) (*internal.EmailData, error) {
+	return internal.ReadEmlFile(filePath)
+}
+
+// ReadPEC reads a PEC (Posta Elettronica Certificata) .eml file.
+// PEC emails are Italian certified emails that contain an inner email message
+// wrapped in a certification envelope with digital signatures.
+//
+// This method extracts and returns the inner original email, ignoring the
+// certification wrapper (daticert.xml and signature files are available as attachments).
+//
+// Parameters:
+//   - filePath: Absolute path to the PEC .eml file
+//
+// Returns:
+//   - *internal.EmailData: The inner original email content
+//   - error: Any parsing errors
+func (a *App) ReadPEC(filePath string) (*internal.EmailData, error) {
+	return internal.ReadPecInnerEml(filePath)
+}
+
+// ReadMSG reads a Microsoft Outlook .msg file and returns the email data.
+// MSG files use the CFB (Compound File Binary) format, which is a proprietary
+// format used by Microsoft Office applications.
+//
+// This method uses an external converter to properly parse the MSG format
+// and extract headers, body, and attachments.
+//
+// Parameters:
+//   - filePath: Absolute path to the .msg file
+//   - useExternalConverter: Whether to use external conversion (currently always true)
+//
+// Returns:
+//   - *internal.EmailData: Parsed email data
+//   - error: Any parsing or conversion errors
+func (a *App) ReadMSG(filePath string, useExternalConverter bool) (*internal.EmailData, error) {
+	// The useExternalConverter parameter is kept for API compatibility
+	// but the implementation always uses the internal MSG reader
+	return internal.ReadMsgFile(filePath)
+}
+
+// ReadMSGOSS reads a .msg file using the open-source parser.
+// This is an alternative entry point that explicitly uses the OSS implementation.
+//
+// Parameters:
+//   - filePath: Absolute path to the .msg file
+//
+// Returns:
+//   - *internal.EmailData: Parsed email data
+//   - error: Any parsing errors
+func (a *App) ReadMSGOSS(filePath string) (*internal.EmailData, error) {
+	return internal.ReadMsgFile(filePath)
+}
+
+// ShowOpenFileDialog displays the system file picker dialog filtered for email files.
+// This allows users to browse and select .eml or .msg files to open.
+//
+// The dialog is configured with filters for:
+//   - EML files (*.eml)
+//   - MSG files (*.msg)
+//
+// Returns:
+//   - string: The selected file path, or empty string if cancelled
+//   - error: Any dialog errors
+func (a *App) ShowOpenFileDialog() (string, error) {
+	return internal.ShowFileDialog(a.ctx)
+}