package com.gcc_manpower.gccadjustmentmanagement.controller;

import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.context.HttpSessionSecurityContextRepository;
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.web.multipart.MultipartFile;

import com.gcc_manpower.gccadjustmentmanagement.service.AdjustmentService;
import com.gcc_manpower.service.AppUserService;

import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpSession;

@Controller
@RequestMapping("/gccadjustmentmanagement")
public class AdjustmentController {

    @Autowired
    private AdjustmentService adjustmentService;

    @Autowired
    private AppUserService appUserService;

    @Autowired
    private AuthenticationManager authenticationManager;

    @Value("${adjustment.upload.path:gccadjustmentmanagementfiles}")
    private String adjustmentUploadPathConfig;

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

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

        model.addAttribute("isLoggedIn", true);
        model.addAttribute("isAdmin", isAdmin);
        model.addAttribute("usrName", username);
        model.addAttribute("curPage", "gccadjustmentmanagement");

        return "gccadjustmentmanagement/dashboard";
    }

    @GetMapping("/details")
    public String viewDetails(Model model, HttpSession session) {
        String username = (String) session.getAttribute("adj_usrName");
        if (username == null) {
            return "redirect:/gccadjustmentmanagement/login";
        }

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

        model.addAttribute("isLoggedIn", true);
        model.addAttribute("isAdmin", isAdmin);
        model.addAttribute("usrName", username);
        model.addAttribute("curPage", "gccadjustmentmanagement");

        return "gccadjustmentmanagement/details";
    }

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

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

        Map<String, Object> response = new HashMap<>();

        try {
            UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(usrName,
                    usrPass);
            Authentication authentication = authenticationManager.authenticate(authenticationToken);

            SecurityContextHolder.getContext().setAuthentication(authentication);
            session.setAttribute(HttpSessionSecurityContextRepository.SPRING_SECURITY_CONTEXT_KEY,
                    SecurityContextHolder.getContext());

            String role = authentication.getAuthorities().stream()
                    .map(auth -> auth.getAuthority().replace("ROLE_", ""))
                    .findFirst()
                    .orElse("USER");

            session.setAttribute("adj_usrName", usrName);
            session.setAttribute("adj_usrRole", role);
            session.setMaxInactiveInterval(1800); // 30 minutes session timeout
            response.put("result", true);
            response.put("usrName", usrName);
        } catch (AuthenticationException e) {
            response.put("result", false);
            response.put("error", e.getMessage() != null ? e.getMessage() : "Invalid username or password!");
        }

        return response;
    }

    @GetMapping("/logout")
    public String logout(HttpSession session, HttpServletRequest request) {
        SecurityContextHolder.clearContext();
        if (session != null) {
            session.removeAttribute("adj_usrName");
            session.removeAttribute("adj_usrRole");
            session.invalidate();
        }
        request.getSession(true);
        return "redirect:/gccadjustmentmanagement/login";
    }

    @GetMapping("/api/advance-types")
    @ResponseBody
    public List<Map<String, Object>> getAdvanceTypes(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getAdvanceTypes();
    }

    @GetMapping("/api/fund-types")
    @ResponseBody
    public List<Map<String, Object>> getFundTypes(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getFundTypes();
    }

    @GetMapping("/api/file-statuses")
    @ResponseBody
    public List<Map<String, Object>> getFileStatuses(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getFileStatusList();
    }

    @GetMapping("/api/list")
    @ResponseBody
    public List<Map<String, Object>> getFilesList(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getAllFiles();
    }

    @GetMapping("/api/list-all")
    @ResponseBody
    public List<Map<String, Object>> getFilesListIncludingDeleted(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getAllFilesIncludingDeleted();
    }

    @GetMapping("/api/pending/fi-available")
    @ResponseBody
    public List<Map<String, Object>> getPendingFIAvailable(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getPendingFinalInvoiceAvailableFiles();
    }

    @GetMapping("/api/pending/fi-not-available")
    @ResponseBody
    public List<Map<String, Object>> getPendingFINotAvailable(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getPendingFinalInvoiceNotAvailableFiles();
    }

    @GetMapping("/api/pending/ready-to-close")
    @ResponseBody
    public List<Map<String, Object>> getReadyToClose(HttpSession session) {
        if (session.getAttribute("adj_usrName") == null) {
            return Collections.emptyList();
        }
        return adjustmentService.getReadyToCloseFiles();
    }

    @PostMapping("/api/save")
    @ResponseBody
    public Map<String, Object> saveAdjustment(
            @RequestParam(value = "id", required = false) Integer id,
            @RequestParam(value = "vend_name", required = false) String vendName,
            @RequestParam(value = "fin_year", required = false) String finYear,
            @RequestParam(value = "subject", required = false) String subject,
            @RequestParam(value = "adv_type_id", required = false) String advTypeId,
            @RequestParam(value = "fund_type_id", required = false) String fundTypeId,
            @RequestParam(value = "bal_amt", required = false) Double balAmt,
            @RequestParam(value = "file_remark", required = false) String fileRemark,
            @RequestParam(value = "file_data_num", required = false) String fileDataNum,
            @RequestParam(value = "pi_amt", required = false) Double piAmt,
            @RequestParam(value = "pi_file_gen_date", required = false) String piFileGenDate,
            @RequestParam(value = "fi_amt", required = false) String fiAmt,
            @RequestParam(value = "fi_file_gen_date", required = false) String fiFileGenDate,
            @RequestParam(value = "tc_file_gen_date", required = false) String tcFileGenDate,
            @RequestParam(value = "ejv_num", required = false) String ejvNum,
            @RequestParam(value = "ejv_num_file_gen_date", required = false) String ejvNumFileGenDate,
            @RequestParam(value = "as_file_gen_date", required = false) String asFileGenDate,
            @RequestParam(value = "as_final_file_gen_date", required = false) String asFinalFileGenDate,
            @RequestParam(value = "ac_code", required = false) String acCode,
            @RequestParam(value = "file_available_status", required = false) String fileAvailableStatus,
            @RequestParam(value = "rtgs_date", required = false) String rtgsDate,
            @RequestParam(value = "dc_completed_date", required = false) String dcCompletedDate,
            @RequestParam(value = "file", required = false) MultipartFile file,
            @RequestParam(value = "poFile", required = false) MultipartFile poFile,
            @RequestParam(value = "dcFile", required = false) MultipartFile dcFile,
            @RequestParam(value = "irFile", required = false) MultipartFile irFile,
            @RequestParam(value = "srFile", required = false) MultipartFile srFile,
            @RequestParam(value = "piFile", required = false) MultipartFile piFile,
            @RequestParam(value = "fiFile", required = false) MultipartFile fiFile,
            @RequestParam(value = "tcFile", required = false) MultipartFile tcFile,
            @RequestParam(value = "rtgsFile", required = false) MultipartFile rtgsFile,
            @RequestParam(value = "ejvFile", required = false) MultipartFile ejvFile,
            @RequestParam(value = "asFile", required = false) MultipartFile asFile,
            @RequestParam(value = "asFinalFile", required = false) MultipartFile asFinalFile,
            @RequestParam(value = "file_status_id", required = false) Integer fileStatusId,
            HttpSession session) {

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

        try {
            Map<String, Object> existing = null;
            if (id != null) {
                existing = adjustmentService.getAdjustmentFileById(id);
                if (existing == null) {
                    response.put("success", false);
                    response.put("error", "Record not found.");
                    return response;
                }
            }

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

            // Save files or keep existing
            String filePath = saveFile(file, "file", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("file_path") : null);
            String poPath = saveFile(poFile, "po", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("po_file_path") : null);
            String dcPath = saveFile(dcFile, "dc", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("dc_file_path") : null);
            String irPath = saveFile(irFile, "ir", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("ir_file_path") : null);
            String srPath = saveFile(srFile, "sr", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("sr_filepath") : null);
            String piPath = saveFile(piFile, "pi", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("pi_file_path") : null);
            String fiPath = saveFile(fiFile, "fi", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("fi_file_path") : null);
            String tcPath = saveFile(tcFile, "tc", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("tc_file_path") : null);
            String rtgsPath = saveFile(rtgsFile, "rtgs", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("rtgs_file_path") : null);
            String ejvPath = saveFile(ejvFile, "ejv", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("ejv_num_file_path") : null);
            String asPath = saveFile(asFile, "as", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("as_file_path") : null);
            String asFinalPath = saveFile(asFinalFile, "as_final", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("as_final_file_path") : null);

            // Build data map
            Map<String, Object> data = new HashMap<>();
            if (id != null)
                data.put("id", id);
            data.put("vend_name", vendName);
            data.put("fin_year", finYear);
            data.put("subject", subject);
            data.put("adv_type_id", advTypeId);
            data.put("fund_type_id", fundTypeId);
            data.put("bal_amt", balAmt);
            data.put("file_remark", fileRemark);
            data.put("file_data_num", fileDataNum);
            data.put("pi_amt", piAmt);
            data.put("pi_file_gen_date", piFileGenDate);
            data.put("fi_amt", fiAmt);
            data.put("fi_file_gen_date", fiFileGenDate);
            data.put("tc_file_gen_date", tcFileGenDate);
            data.put("ejv_num", ejvNum);
            data.put("ejv_num_file_gen_date", ejvNumFileGenDate);
            data.put("as_file_gen_date", asFileGenDate);
            data.put("as_final_file_gen_date", asFinalFileGenDate);
            data.put("ac_code", acCode);
            data.put("file_available_status", fileAvailableStatus);
            data.put("rtgs_date", rtgsDate);
            data.put("dc_completed_date", dcCompletedDate);
            data.put("file_status_id", fileStatusId);

            // Paths
            data.put("file_path", filePath);
            data.put("po_file_path", poPath);
            data.put("dc_file_path", dcPath);
            data.put("ir_file_path", irPath);
            data.put("sr_filepath", srPath);
            data.put("pi_file_path", piPath);
            data.put("fi_file_path", fiPath);
            data.put("tc_file_path", tcPath);
            data.put("rtgs_file_path", rtgsPath);
            data.put("ejv_num_file_path", ejvPath);
            data.put("as_file_path", asPath);
            data.put("as_final_file_path", asFinalPath);

            boolean saved = adjustmentService.saveAdjustmentFile(data, username);
            if (saved) {
                response.put("success", true);
                response.put("message", "Adjustment file details saved successfully.");
            } else {
                response.put("success", false);
                response.put("error", "Failed to save details in database.");
            }
        } catch (Exception e) {
            response.put("success", false);
            response.put("error", "Error occurred: " + e.getMessage());
            e.printStackTrace();
        }

        return response;
    }

    @PostMapping("/api/delete")
    @ResponseBody
    public Map<String, Object> deleteAdjustment(
            @RequestParam("id") Integer id,
            @RequestParam(value = "remarks", required = false) String remarks,
            HttpSession session) {

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

        boolean deleted = adjustmentService.deleteAdjustmentFile(id, remarks != null ? remarks : "Deleted by user",
                username);
        if (deleted) {
            response.put("success", true);
            response.put("message", "Record deleted successfully.");
        } else {
            response.put("success", false);
            response.put("error", "Failed to delete record.");
        }

        return response;
    }

    @PostMapping("/api/update-ejv")
    @ResponseBody
    public Map<String, Object> updateEJV(
            @RequestParam("id") Integer id,
            @RequestParam("ejv_num") String ejvNum,
            @RequestParam(value = "ejvFile", required = false) MultipartFile ejvFile,
            HttpSession session) {

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

        try {
            Map<String, Object> existing = adjustmentService.getAdjustmentFileById(id);
            if (existing == null) {
                response.put("success", false);
                response.put("error", "Record not found.");
                return response;
            }

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

            String fileDataNum = (String) existing.get("file_data_num");
            String ejvPath = saveFile(ejvFile, "ejv", fileDataNum, uploadDir,
                    existing != null ? (String) existing.get("ejv_num_file_path") : null);

            boolean updated = adjustmentService.updateEJV(id, ejvNum, ejvPath, username);
            if (updated) {
                response.put("success", true);
                response.put("message", "EJV details updated successfully.");
            } else {
                response.put("success", false);
                response.put("error", "Failed to update EJV details in database.");
            }
        } catch (Exception e) {
            response.put("success", false);
            response.put("error", "Error occurred: " + e.getMessage());
            e.printStackTrace();
        }

        return response;
    }

    private String saveFile(MultipartFile f, String category, String fileNum, File dir, String currentPath)
            throws Exception {
        if (f == null || f.isEmpty()) {
            return currentPath;
        }

        // Clean fileNum
        String cleanFileNum = "unknown";
        if (fileNum != null && !fileNum.trim().isEmpty()) {
            // Remove illegal characters, but allow slashes / and \ for hierarchy
            cleanFileNum = fileNum.trim().replaceAll("[^a-zA-Z0-9.\\/\\\\_-]", "_");
            // Normalize path separators to forward slash /
            cleanFileNum = cleanFileNum.replace('\\', '/');
        }

        // Save files inside the physical "uploads" directory in the project root
        File projectRoot = new File(".").getAbsoluteFile();
        String subPath = "uploads/file-data/" + cleanFileNum + "/" + category.toUpperCase();
        File folder = new File(projectRoot, subPath).getAbsoluteFile();
        if (!folder.exists()) {
            folder.mkdirs();
        }

        String orig = f.getOriginalFilename();
        String ext = orig != null && orig.lastIndexOf('.') > 0 ? orig.substring(orig.lastIndexOf('.')) : ".pdf";
        String cleanName = orig != null
                ? orig.substring(0, orig.lastIndexOf('.')).replaceAll("[^a-zA-Z0-9.-]", "_") + ext
                : (category + "_" + System.currentTimeMillis() + ext);
        File dest = new File(folder, cleanName).getAbsoluteFile();
        f.transferTo(dest);

        return "uploads/file-data/" + cleanFileNum + "/" + category.toUpperCase() + "/" + cleanName;
    }
}