feat: Implement letter service with CRUD operations and message handling

- Added letter service to manage letters, including listing, creating, and editing letters and messages.
- Implemented functionality for sending and receiving messages within letters.
- Introduced pagination for letter listings and message retrieval.
- Added attachment upload capabilities for letters.
- Created detailed responses for letter and message retrieval.

feat: Introduce stats service for user statistics

- Added a service to retrieve user statistics, including newest and online citizens.

feat: Create ticket service for user support tickets

- Implemented ticket management service with functionalities to create, reply, and update tickets.
- Added support for ticket categories and their management.

feat: Add verification service for user account verification

- Implemented functionality to send verification emails for account activation.

feat: Develop warning service for user warnings

- Added service to issue warnings to users, deactivate warnings, and list user warnings.

feat: Create email templates for account status notifications

- Added HTML templates for account ban and disable notifications.

feat: Define request and response types for account, ticket, letter, and warning services

- Created structured request and response types for various services to ensure consistent data handling.

feat: Implement utility functions for authentication and sanitization

- Added functions for validating user hierarchy and sanitizing HTML input.
- Implemented token generation and hashing utilities for secure operations.

1 files changed, 165 insertions, 0 deletions

diff --git a/shrine/controllers/letter.go b/shrine/controllers/letter.go
new file mode 100644
index 0000000..10696f1
--- /dev/null
+++ b/shrine/controllers/letter.go
@@ -0,0 +1,165 @@
+package controllers
+
+import (
+	"shrine/messages"
+	"shrine/services"
+	"shrine/types/letter"
+	"shrine/utils/auth"
+	"shrine/utils/meta"
+	"shrine/utils/shortcuts"
+
+	"github.com/gofiber/fiber/v2"
+)
+
+func ListLettersController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	pagination := meta.Paginate(context)
+
+	items, total := services.ListLetters(citizen.ID, pagination)
+	return shortcuts.Success(context, pagination.Response(items, total))
+}
+
+func GetLetterController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+	pagination := meta.Paginate(context)
+
+	result, serviceErr := services.GetLetter(ref, citizen.ID, pagination)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Success(context, result)
+}
+
+func CreateLetterController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+
+	body, err := meta.Body[letter.CreateRequest](context)
+	if err != nil {
+		return shortcuts.BadRequest(context, err)
+	}
+
+	result, serviceErr := services.CreateLetter(citizen.ID, body)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Created(context, result)
+}
+
+func SendMessageController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+
+	body, err := meta.Body[letter.SendMessageRequest](context)
+	if err != nil {
+		return shortcuts.BadRequest(context, err)
+	}
+
+	result, serviceErr := services.SendLetterMessage(ref, citizen.ID, body)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Created(context, result)
+}
+
+func EditMessageController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+	messageRef := meta.Request(context).MustHave().Param("messageRef")
+
+	body, err := meta.Body[letter.EditMessageRequest](context)
+	if err != nil {
+		return shortcuts.BadRequest(context, err)
+	}
+
+	result, serviceErr := services.EditLetterMessage(ref, messageRef, citizen.ID, body)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Success(context, result)
+}
+
+func DeleteMessageController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+	messageRef := meta.Request(context).MustHave().Param("messageRef")
+
+	serviceErr := services.DeleteLetterMessage(ref, messageRef, citizen.ID)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.NoContent(context)
+}
+
+func RenameLetterController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+
+	body, err := meta.Body[letter.RenameRequest](context)
+	if err != nil {
+		return shortcuts.BadRequest(context, err)
+	}
+
+	result, serviceErr := services.RenameLetter(ref, citizen.ID, body)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Success(context, result)
+}
+
+func LeaveLetterController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+
+	result, serviceErr := services.LeaveLetter(ref, citizen.ID)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Success(context, result)
+}
+
+func RemoveParticipantController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+	ref := meta.Request(context).MustHave().Param("ref")
+
+	body, err := meta.Body[letter.RemoveParticipantRequest](context)
+	if err != nil {
+		return shortcuts.BadRequest(context, err)
+	}
+
+	result, serviceErr := services.RemoveLetterParticipant(ref, citizen.ID, body)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Success(context, result)
+}
+
+func UploadAttachmentController(context *fiber.Ctx) error {
+	citizen := auth.GetUser(context)
+
+	file, err := context.FormFile("file")
+	if err != nil {
+		return shortcuts.BadRequest(context, fiber.NewError(fiber.StatusBadRequest, messages.FileRequired))
+	}
+
+	source, err := file.Open()
+	if err != nil {
+		return shortcuts.InternalServerError(context, err)
+	}
+	defer source.Close()
+
+	result, serviceErr := services.UploadLetterAttachment(citizen.ID, file.Filename, file.Size, file.Header.Get("Content-Type"), source)
+	if serviceErr != nil {
+		return shortcuts.HandleError(context, serviceErr)
+	}
+
+	return shortcuts.Created(context, result)
+}
\ No newline at end of file