package com.gcc_manpower.gcctonermanagement.controller;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import com.gcc_manpower.gcctonermanagement.service.TonerService;
import com.gcc_manpower.service.AppUserService;

import jakarta.servlet.http.HttpSession;

@Controller
@RequestMapping("/gcctonermanagement")
public class TonerController {

    @Autowired
    private AppUserService appUserService;

    @Autowired
    private TonerService tonerService;

    @Value("${toner.upload.path:gcctonermanagementfiles}")
    private String tonerUploadPathConfig;

    @GetMapping({ "", "/", "/upload" })
    public String viewDashboard(Model model, HttpSession session) {
        String username = (String) session.getAttribute("toner_usrName");
        if (username == null) {
            return "redirect:/gcctonermanagement/login";
        }

        String usrRole = (String) session.getAttribute("toner_usrRole");
        boolean isAdmin = "ADMIN".equalsIgnoreCase(usrRole);

        // List<Map<String, Object>> vendorDetails =
        // appUserService.getVendorDetailsWithCounts();

        model.addAttribute("isLoggedIn", true);
        model.addAttribute("isAdmin", isAdmin);
        model.addAttribute("usrName", username);
        model.addAttribute("curPage", "gcctonermanagement");
        // model.addAttribute("vendorDetails", vendorDetails);

        return "gcctonermanagement/upload";
    }

    @GetMapping("/login")
    public String login(HttpSession session) {
        return "gcctonermanagement/login";
    }

    @PostMapping("/api/login")
    @ResponseBody
    public Map<String, Object> validateLogin(
            @RequestParam("usrName") String usrName,
            @RequestParam("usrPass") String usrPass,
            HttpSession session) {

        Map<String, Object> authResult = appUserService.authenticate(usrName, usrPass);
        Map<String, Object> response = new HashMap<>();

        if (Boolean.TRUE.equals(authResult.get("success"))) {
            session.setAttribute("toner_usrName", authResult.get("usrName"));
            session.setAttribute("toner_usrRole", authResult.get("usrRole"));
            session.setMaxInactiveInterval(1800); // 30 minutes session timeout
            response.put("result", true);
            response.put("usrName", authResult.get("usrName"));
        } else {
            response.put("result", false);
            response.put("error", authResult.get("error"));
        }

        return response;
    }

    @GetMapping("/logout")
    public String logoutGet(HttpSession session) {
        session.removeAttribute("toner_usrName");
        session.removeAttribute("toner_usrRole");
        return "redirect:/gcctonermanagement/login";
    }

    @GetMapping("/api/printers")
    @ResponseBody
    public List<Map<String, Object>> getPrinters(HttpSession session) {
        if (session.getAttribute("toner_usrName") == null) {
            return java.util.Collections.emptyList();
        }
        return tonerService.getActivePrinters();
    }

    @GetMapping("/api/toners")
    @ResponseBody
    public List<Map<String, Object>> getToners(@RequestParam("pid") int pid, HttpSession session) {
        if (session.getAttribute("toner_usrName") == null) {
            return java.util.Collections.emptyList();
        }
        return tonerService.getActiveTonersByPrinter(pid);
    }

    @PostMapping("/api/upload")
    @ResponseBody
    public Map<String, Object> uploadToner(
            @RequestParam("companyName") String companyName,
            @RequestParam("pid") int pid,
            @RequestParam("tid") int tid,
            @RequestParam("qty") String qty,
            @RequestParam(value = "dcFile", required = false) MultipartFile dcFile,
            @RequestParam(value = "userRequestFile", required = false) MultipartFile userRequestFile,
            @RequestParam(value = "finalDeliveredFile", required = false) MultipartFile finalDeliveredFile,
            HttpSession session) {

        Map<String, Object> response = new HashMap<>();
        String username = (String) session.getAttribute("toner_usrName");
        if (username == null) {
            response.put("success", false);
            response.put("error", "Unauthorized access. Please log in.");
            return response;
        }

        // Validate PDF extension on non-empty files
        if (dcFile != null && !dcFile.isEmpty() && !isPdfFile(dcFile)) {
            response.put("success", false);
            response.put("error", "Delivery Challan file must be a PDF.");
            return response;
        }
        if (userRequestFile != null && !userRequestFile.isEmpty() && !isPdfFile(userRequestFile)) {
            response.put("success", false);
            response.put("error", "User Request file must be a PDF.");
            return response;
        }
        if (finalDeliveredFile != null && !finalDeliveredFile.isEmpty() && !isPdfFile(finalDeliveredFile)) {
            response.put("success", false);
            response.put("error", "Final Delivered file must be a PDF.");
            return response;
        }

        try {
            File uploadDir = new File(tonerUploadPathConfig).getAbsoluteFile();
            if (!uploadDir.exists()) {
                uploadDir.mkdirs();
            }

            // Save files
            String dcPath = saveUploadedFile(dcFile, "dc", uploadDir);
            String userRequestPath = saveUploadedFile(userRequestFile, "user_request", uploadDir);
            String finalDeliveredPath = saveUploadedFile(finalDeliveredFile, "final_delivered", uploadDir);

            boolean saved = tonerService.saveInventoryDetails(
                    companyName.trim(),
                    pid,
                    tid,
                    qty.trim(),
                    dcPath,
                    userRequestPath,
                    finalDeliveredPath,
                    username);

            if (saved) {
                response.put("success", true);
                response.put("message", "Toner details saved successfully.");
            } else {
                // Delete newly saved files on DB insert failure
                deleteFileIfExists(dcPath, uploadDir);
                deleteFileIfExists(userRequestPath, uploadDir);
                deleteFileIfExists(finalDeliveredPath, uploadDir);
                response.put("success", false);
                response.put("error", "Failed to save registration details in the database.");
            }
        } catch (Exception e) {
            response.put("success", false);
            response.put("error", "An error occurred during saving: " + e.getMessage());
            e.printStackTrace();
        }

        return response;
    }

    private boolean isPdfFile(MultipartFile file) {
        String originalFilename = file.getOriginalFilename();
        if (originalFilename == null)
            return false;
        return originalFilename.toLowerCase().endsWith(".pdf");
    }

    private String saveUploadedFile(MultipartFile file, String prefix, File uploadDir) throws Exception {
        if (file == null || file.isEmpty()) {
            return null;
        }
        String originalFilename = file.getOriginalFilename();
        String ext = ".pdf"; // Since we only allow PDFs

        // Clean filename, make it unique
        String savedFilename = prefix + "_" + System.currentTimeMillis() + ext;
        File destFile = new File(uploadDir, savedFilename).getAbsoluteFile();
        file.transferTo(destFile);

        return "/gcctonermanagementfiles/" + savedFilename;
    }

    private void deleteFileIfExists(String webPath, File uploadDir) {
        if (webPath == null || webPath.isEmpty())
            return;
        try {
            String filename = webPath.substring(webPath.lastIndexOf('/') + 1);
            File file = new File(uploadDir, filename).getAbsoluteFile();
            if (file.exists()) {
                file.delete();
            }
        } catch (Exception e) {
            System.err.println("Error deleting file: " + e.getMessage());
        }
    }
}