package handlers

import (
	"mime/multipart"
	"net/http"
	"strconv"
	"strings"
	"time"

	"github.com/labstack/echo/v4"
	"github.com/shopspring/decimal"

	"github.com/treytartt/honeydue-api/internal/apperrors"
	"github.com/treytartt/honeydue-api/internal/dto/requests"
	"github.com/treytartt/honeydue-api/internal/dto/responses"
	"github.com/treytartt/honeydue-api/internal/i18n"
	"github.com/treytartt/honeydue-api/internal/middleware"
	"github.com/treytartt/honeydue-api/internal/models"
	"github.com/treytartt/honeydue-api/internal/repositories"
	"github.com/treytartt/honeydue-api/internal/services"
)

// DocumentHandler handles document-related HTTP requests
type DocumentHandler struct {
	documentService *services.DocumentService
	storageService  *services.StorageService
}

// NewDocumentHandler creates a new document handler
func NewDocumentHandler(documentService *services.DocumentService, storageService *services.StorageService) *DocumentHandler {
	return &DocumentHandler{
		documentService: documentService,
		storageService:  storageService,
	}
}

// ListDocuments handles GET /api/documents/
func (h *DocumentHandler) ListDocuments(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}

	// Build filter from supported query params.
	var filter *repositories.DocumentFilter
	if c.QueryParam("residence") != "" || c.QueryParam("document_type") != "" ||
		c.QueryParam("is_active") != "" || c.QueryParam("expiring_soon") != "" ||
		c.QueryParam("search") != "" {
		filter = &repositories.DocumentFilter{
			DocumentType: c.QueryParam("document_type"),
			Search:       c.QueryParam("search"),
		}
		if rid := c.QueryParam("residence"); rid != "" {
			if parsed, err := strconv.ParseUint(rid, 10, 32); err == nil {
				residenceID := uint(parsed)
				filter.ResidenceID = &residenceID
			}
		}
		if ia := c.QueryParam("is_active"); ia != "" {
			isActive := ia == "true" || ia == "1"
			filter.IsActive = &isActive
		}
		if es := c.QueryParam("expiring_soon"); es != "" {
			if parsed, err := strconv.Atoi(es); err == nil {
				if parsed < 1 || parsed > 3650 {
					return apperrors.BadRequest("error.days_out_of_range")
				}
				filter.ExpiringSoon = &parsed
			}
		}
	}

	response, err := h.documentService.ListDocuments(user.ID, filter)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}

// GetDocument handles GET /api/documents/:id/
func (h *DocumentHandler) GetDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	response, err := h.documentService.GetDocument(uint(documentID), user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}

// ListWarranties handles GET /api/documents/warranties/
func (h *DocumentHandler) ListWarranties(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	response, err := h.documentService.ListWarranties(user.ID)
	if err != nil {
		return apperrors.Internal(err)
	}
	return c.JSON(http.StatusOK, response)
}

// CreateDocument handles POST /api/documents/
// Supports both JSON and multipart form data (for file uploads)
func (h *DocumentHandler) CreateDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	var req requests.CreateDocumentRequest

	contentType := c.Request().Header.Get("Content-Type")

	// Check if this is a multipart form request (file upload)
	if strings.HasPrefix(contentType, "multipart/form-data") {
		// Parse multipart form
		if err := c.Request().ParseMultipartForm(32 << 20); err != nil { // 32MB max
			return apperrors.BadRequest("error.failed_to_parse_form")
		}

		// Parse residence_id (required)
		residenceIDStr := c.FormValue("residence_id")
		if residenceIDStr == "" {
			return apperrors.BadRequest("error.residence_id_required")
		}
		residenceID, err := strconv.ParseUint(residenceIDStr, 10, 32)
		if err != nil {
			return apperrors.BadRequest("error.invalid_residence_id")
		}
		req.ResidenceID = uint(residenceID)

		// Parse title (required)
		req.Title = c.FormValue("title")
		if req.Title == "" {
			return apperrors.BadRequest("error.title_required")
		}

		// Parse optional fields
		req.Description = c.FormValue("description")
		req.Vendor = c.FormValue("vendor")
		req.SerialNumber = c.FormValue("serial_number")
		req.ModelNumber = c.FormValue("model_number")

		// Parse document_type
		if docType := c.FormValue("document_type"); docType != "" {
			dt := models.DocumentType(docType)
			req.DocumentType = dt
		}

		// Parse task_id (optional)
		if taskIDStr := c.FormValue("task_id"); taskIDStr != "" {
			if taskID, err := strconv.ParseUint(taskIDStr, 10, 32); err == nil {
				tid := uint(taskID)
				req.TaskID = &tid
			}
		}

		// Parse purchase_price (optional)
		if priceStr := c.FormValue("purchase_price"); priceStr != "" {
			if price, err := decimal.NewFromString(priceStr); err == nil {
				req.PurchasePrice = &price
			}
		}

		// Parse purchase_date (optional)
		if dateStr := c.FormValue("purchase_date"); dateStr != "" {
			if t, err := time.Parse(time.RFC3339, dateStr); err == nil {
				req.PurchaseDate = &t
			} else if t, err := time.Parse("2006-01-02", dateStr); err == nil {
				req.PurchaseDate = &t
			}
		}

		// Parse expiry_date (optional)
		if dateStr := c.FormValue("expiry_date"); dateStr != "" {
			if t, err := time.Parse(time.RFC3339, dateStr); err == nil {
				req.ExpiryDate = &t
			} else if t, err := time.Parse("2006-01-02", dateStr); err == nil {
				req.ExpiryDate = &t
			}
		}

		// Handle file upload (look for "file", "document", or "image" field)
		var uploadedFile *multipart.FileHeader
		for _, fieldName := range []string{"file", "document", "image", "images"} {
			if file, err := c.FormFile(fieldName); err == nil {
				uploadedFile = file
				break
			}
		}

		if uploadedFile != nil {
			if h.storageService == nil {
				return apperrors.Internal(nil)
			}
			result, err := h.storageService.Upload(uploadedFile, "documents")
			if err != nil {
				return apperrors.BadRequest("error.failed_to_upload_file")
			}
			req.FileURL = result.URL
			req.FileName = result.FileName
			req.MimeType = result.MimeType
			fileSize := result.FileSize
			req.FileSize = &fileSize
		}
	} else {
		// Standard JSON request
		if err := c.Bind(&req); err != nil {
			return apperrors.BadRequest("error.invalid_request")
		}
	}

	if err := c.Validate(&req); err != nil {
		return err
	}

	response, err := h.documentService.CreateDocument(&req, user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusCreated, response)
}

// UpdateDocument handles PUT/PATCH /api/documents/:id/
func (h *DocumentHandler) UpdateDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	var req requests.UpdateDocumentRequest
	if err := c.Bind(&req); err != nil {
		return apperrors.BadRequest("error.invalid_request")
	}
	if err := c.Validate(&req); err != nil {
		return err
	}

	response, err := h.documentService.UpdateDocument(uint(documentID), user.ID, &req)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}

// DeleteDocument handles DELETE /api/documents/:id/
func (h *DocumentHandler) DeleteDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	err = h.documentService.DeleteDocument(uint(documentID), user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, responses.MessageResponse{Message: i18n.LocalizedMessage(c, "message.document_deleted")})
}

// ActivateDocument handles POST /api/documents/:id/activate/
func (h *DocumentHandler) ActivateDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	response, err := h.documentService.ActivateDocument(uint(documentID), user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}

// DeactivateDocument handles POST /api/documents/:id/deactivate/
func (h *DocumentHandler) DeactivateDocument(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	response, err := h.documentService.DeactivateDocument(uint(documentID), user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}

// UploadDocumentImage handles POST /api/documents/:id/images/
func (h *DocumentHandler) UploadDocumentImage(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	// Parse multipart form
	if err := c.Request().ParseMultipartForm(32 << 20); err != nil {
		return apperrors.BadRequest("error.failed_to_parse_form")
	}

	// Look for file in common field names
	var uploadedFile *multipart.FileHeader
	for _, fieldName := range []string{"image", "file"} {
		if file, err := c.FormFile(fieldName); err == nil {
			uploadedFile = file
			break
		}
	}

	if uploadedFile == nil {
		return apperrors.BadRequest("error.no_file_provided")
	}

	if h.storageService == nil {
		return apperrors.Internal(nil)
	}

	result, err := h.storageService.Upload(uploadedFile, "images")
	if err != nil {
		return apperrors.BadRequest("error.failed_to_upload_file")
	}

	caption := c.FormValue("caption")

	response, err := h.documentService.UploadDocumentImage(uint(documentID), user.ID, result.URL, caption)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusCreated, response)
}

// DeleteDocumentImage handles DELETE /api/documents/:id/images/:imageId/
func (h *DocumentHandler) DeleteDocumentImage(c echo.Context) error {
	user, err := middleware.MustGetAuthUser(c)
	if err != nil {
		return err
	}
	documentID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_document_id")
	}

	imageID, err := strconv.ParseUint(c.Param("imageId"), 10, 32)
	if err != nil {
		return apperrors.BadRequest("error.invalid_image_id")
	}

	response, err := h.documentService.DeleteDocumentImage(uint(documentID), uint(imageID), user.ID)
	if err != nil {
		return err
	}
	return c.JSON(http.StatusOK, response)
}