package handlers

import (
	"encoding/json"
	"net/http"

	"github.com/scanner/backend/middleware"
	"github.com/scanner/backend/models"
	"github.com/scanner/backend/services"
)

type FileHandler struct {
	fileConverter *services.FileConverter
}

func NewFileHandler(fileConverter *services.FileConverter) *FileHandler {
	return &FileHandler{fileConverter: fileConverter}
}

func (h *FileHandler) MergeFiles(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
		return
	}

	middleware.ApplyCors(w, r)

	var mergeRequest models.MergeRequest
	err := json.NewDecoder(r.Body).Decode(&mergeRequest)
	if err != nil {
		http.Error(w, "Invalid request body", http.StatusBadRequest)
		return
	}

	if len(mergeRequest.Filenames) < 2 {
		http.Error(w, "At least two files are required for merging", http.StatusBadRequest)
		return
	}

	files := []string{}
	for _, filename := range mergeRequest.Filenames {
		files = append(files, "/home/backend/var/documents/"+filename)
	}

	mergedFilename, err := h.fileConverter.MergeFiles(files)
	if err != nil {
		http.Error(w, "Failed to merge files: "+err.Error(), http.StatusInternalServerError)
		return
	}

	response := map[string]string{
		"mergedFile": "/files/" + mergedFilename,
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(response)
}