package handlers

import (
	"bytes"
	"io"
	"net/http"
	"os"
	"path/filepath"

	"Yimaru-Backend/internal/domain"

	"github.com/gofiber/fiber/v2"
	"github.com/google/uuid"
	"go.uber.org/zap"
)

func (h *Handler) processAndSaveThumbnail(c *fiber.Ctx, subDir string) (string, error) {
	fileHeader, err := c.FormFile("file")
	if err != nil {
		return "", c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Image file is required", Error: err.Error()})
	}
	if fileHeader.Size > 10*1024*1024 {
		return "", c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "File too large", Error: "Thumbnail image must be <= 10MB"})
	}

	fh, err := fileHeader.Open()
	if err != nil {
		return "", c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to read file", Error: err.Error()})
	}
	defer fh.Close()

	head := make([]byte, 512)
	n, _ := fh.Read(head)
	contentType := http.DetectContentType(head[:n])
	if contentType != "image/jpeg" && contentType != "image/png" && contentType != "image/webp" {
		return "", c.Status(fiber.StatusBadRequest).JSON(domain.ErrorResponse{Message: "Invalid file type", Error: "Only jpg, png and webp images are allowed"})
	}

	rest, err := io.ReadAll(fh)
	if err != nil {
		return "", c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to read file", Error: err.Error()})
	}
	data := append(head[:n], rest...)

	if h.cloudConvertSvc != nil {
		optimized, optErr := h.cloudConvertSvc.OptimizeImage(c.Context(), fileHeader.Filename, bytes.NewReader(data), int64(len(data)), 1200, 80)
		if optErr != nil {
			h.mongoLoggerSvc.Warn("CloudConvert thumbnail optimization failed, using original", zap.Error(optErr))
		} else {
			optimizedData, readErr := io.ReadAll(optimized.Data)
			optimized.Data.Close()
			if readErr == nil {
				data = optimizedData
				contentType = "image/webp"
			}
		}
	}

	if h.minioSvc != nil {
		result, uploadErr := h.minioSvc.Upload(c.Context(), subDir, fileHeader.Filename, bytes.NewReader(data), int64(len(data)), contentType)
		if uploadErr != nil {
			return "", c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to upload file to storage", Error: uploadErr.Error()})
		}
		return "minio://" + result.ObjectKey, nil
	}

	ext := ".jpg"
	if contentType == "image/png" {
		ext = ".png"
	}
	if contentType == "image/webp" {
		ext = ".webp"
	}
	dir := filepath.Join(".", "static", subDir)
	if err := os.MkdirAll(dir, 0o755); err != nil {
		return "", c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to create storage directory", Error: err.Error()})
	}
	filename := uuid.New().String() + ext
	fullpath := filepath.Join(dir, filename)
	if err := os.WriteFile(fullpath, data, 0o644); err != nil {
		return "", c.Status(fiber.StatusInternalServerError).JSON(domain.ErrorResponse{Message: "Failed to save file", Error: err.Error()})
	}
	return "/static/" + subDir + "/" + filename, nil
}