package in.gov.chennaicorporation.gccoffice.pensioner.service;

import java.time.LocalDate;
import java.time.Period;
import java.time.format.DateTimeFormatter;
import java.time.temporal.ChronoUnit;
import java.util.List;
import java.util.Map;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import in.gov.chennaicorporation.gccoffice.configuration.AppConfig;

@Service
@Transactional
public class PendencyAutoConversionService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Autowired
    private AppConfig appConfig;

    @Autowired
    public void setDataSource(@Qualifier("mysqlPensionerDataSource") DataSource dataSource) {
        this.jdbcTemplate = new JdbcTemplate(dataSource);
    }

    /**
     * Main method to process auto-conversion logic.
     * - Fetch records where retirement date has crossed.
     * - Update pensioner details.
     * - Fetch employee details.
     * - Save data into pensioner_details_history and file_movement_history.
     */
    @Transactional
    public boolean processAutoConversion() {
        try {
            // Step 1: Fetch temp IDs that need processing
            List<Map<String, Object>> tempList = getConvertingTempIds();
            if (tempList.isEmpty()) {
                System.out.println("No records found for auto-conversion.");
                return false;
            }

            for (Map<String, Object> tempIdMap : tempList) {
                String tempId = tempIdMap.get("temp_id") != null ? String.valueOf(tempIdMap.get("temp_id")) : null;
                if (tempId == null || tempId.trim().isEmpty()) {
                    System.out.println("Skipping null/empty temp_id.");
                    continue;
                }

                System.out.println("Processing tempId: " + tempId);

                // Step 2: Get file_moved_by value
                String fileMovedBy = getFileMovedByTempId(tempId);
                if (fileMovedBy == null) {
                    System.out.println("Skipping tempId " + tempId + " as fileMovedBy is NULL.");
                    continue;
                }

                // Step 3: Update pensioner_details table
                boolean updated = updateEntryDetails(tempId);
                if (!updated) {
                    System.out.println("Failed to update pensioner_details for tempId: " + tempId);
                    continue;
                }

                // Step 4: Fetch employee details
                List<Map<String, Object>> empDetails = fetchEmployeeDetails(tempId);
                if (empDetails.isEmpty()) {
                    System.out.println("No employee details found for tempId: " + tempId);
                    continue;
                }

                // Step 5: Save history data
                boolean historySaved = saveHistory(empDetails, fileMovedBy);
                if (!historySaved) {
                    System.out.println("Failed to save history for tempId: " + tempId);
                }
            }

            System.out.println("Auto-conversion process completed.");
            return true;
        } catch (Exception e) {
            System.err.println("Exception in processAutoConversion: " + e.getMessage());
            e.printStackTrace();
            return false;
        }
    }

    public List<Map<String, Object>> getConvertingTempIds() {
        String sql = "SELECT temp_id FROM pensioner_details WHERE file_category=1 AND file_status <=8 AND retirement_date <= CURDATE() - 1";
        return jdbcTemplate.queryForList(sql);
    }

    private boolean updateEntryDetails(String tempId) {
        try {
            LocalDate datefield = LocalDate.now();
            String formattedDate = datefield.format(DateTimeFormatter.ofPattern("yyyy-MM-dd"));
            String remarks = "Auto_Conversion";
            int fileCategory = 3;
            String pendingDuration = "yes";
            String reasonForPending = "Retirement Date Crossed while file in Auditing";

            String updateQuery = "UPDATE pensioner_details SET reason_for_pending=?, pending_duration=?, file_category=?, file_moved_date=?, remarks=?, updated_date=CURRENT_TIMESTAMP WHERE temp_id=?";
            int rowsUpdated = jdbcTemplate.update(updateQuery, reasonForPending, pendingDuration, fileCategory, formattedDate, remarks, tempId);

            System.out.println("Updated pensioner_details for tempId: " + tempId + " - Rows affected: " + rowsUpdated);
            return rowsUpdated > 0;
        } catch (Exception e) {
            System.err.println("Exception in updateEntryDetails: " + e.getMessage());
            return false;
        }
    }

    private List<Map<String, Object>> fetchEmployeeDetails(String tempId) {
        String sql = "SELECT * FROM pensioner_details WHERE temp_id=?";
        return jdbcTemplate.queryForList(sql, tempId);
    }

    
    @Transactional
    private boolean saveHistory(List<Map<String, Object>> empDetails, String fileMovedBy) {
        try {
            String empInsertQuery = "INSERT INTO pensioner_details_history (emp_no, emp_name, dept_name, designation, type_of_retirement, " +
                    "retirement_date, retirement_class, file_moved_date, remarks, file_category, file_status, " +
                    "file_entry_type, file_moved_by, dept_id, file_category_name, temp_id, pending_duration, reason_for_pending) " +
                    "VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";

            jdbcTemplate.batchUpdate(empInsertQuery, empDetails, empDetails.size(), (ps, emp) -> {
                ps.setString(1, emp.get("emp_no").toString());
                ps.setString(2, emp.get("emp_name").toString());
                ps.setString(3, emp.get("dept_name").toString());
                ps.setString(4, emp.get("designation").toString());
                ps.setString(5, emp.get("type_of_retirement").toString());
                ps.setString(6, emp.get("retirement_date").toString());
                ps.setString(7, emp.get("retirement_class").toString());
                ps.setString(8, emp.get("file_moved_date").toString());
                ps.setString(9, emp.get("remarks").toString());
                ps.setInt(10, Integer.parseInt(emp.get("file_category").toString()));
                ps.setInt(11, Integer.parseInt(emp.get("file_status").toString()));
                ps.setString(12, emp.get("file_entry_type").toString());
                ps.setString(13, fileMovedBy != null ? fileMovedBy : "");
                ps.setInt(14, Integer.parseInt(emp.get("dept_id").toString()));
                ps.setString(15, emp.get("file_category_name").toString());
                ps.setString(16, emp.get("temp_id").toString());
                ps.setString(17, emp.get("pending_duration") != null ? emp.get("pending_duration").toString() : null);
                ps.setString(18, emp.get("reason_for_pending") != null ? emp.get("reason_for_pending").toString() : null);
            });

            String historyQuery = "INSERT INTO file_movement_history (emp_no, file_moved_date, file_status, file_moved_by, remarks, temp_id) VALUES (?, ?, ?, ?, ?, ?)";

            jdbcTemplate.batchUpdate(historyQuery, empDetails, empDetails.size(), (ps, his) -> {
                ps.setString(1, his.get("emp_no").toString());
                ps.setString(2, his.get("file_moved_date").toString());
                ps.setString(3, his.get("file_status").toString());
                ps.setString(4, fileMovedBy != null ? fileMovedBy : "");
                ps.setString(5, his.get("remarks").toString());
                ps.setString(6, his.get("temp_id").toString());
            });

            System.out.println("Successfully saved history for " + empDetails.size() + " records.");
            return true;
        } catch (Exception e) {
            System.err.println("Exception in saveHistory: " + e.getMessage());
            return false;
        }
    }

    private String getFileMovedByTempId(String tempId) {
        String sql = "SELECT file_moved_by FROM pensioner_details_history WHERE temp_id=? ORDER BY created_date ASC LIMIT 1";
        return jdbcTemplate.queryForObject(sql, String.class, tempId);
    }

    
	public boolean processAutoConversionForTempId(String tempId) {
    try {
        System.out.println("Running auto-conversion for tempId: " + tempId);

        // Step 1: Get fileMovedBy
        String fileMovedBy = getFileMovedByTempId(tempId);
        if (fileMovedBy == null) {
            System.out.println("Skipping tempId " + tempId + " as fileMovedBy is NULL.");
            return false;
        }

        // Step 2: Update pensioner details
        boolean updated = updateEntryDetails(tempId);
        if (!updated) {
            System.out.println("Failed to update pensioner_details for tempId: " + tempId);
            return false;
        }

        // Step 3: Fetch employee details
        List<Map<String, Object>> empDetails = fetchEmployeeDetails(tempId);
        if (empDetails.isEmpty()) {
            System.out.println("No employee details found for tempId: " + tempId);
            return false;
        }

        // Step 4: Save history
        boolean historySaved = saveHistory(empDetails, fileMovedBy);
        if (!historySaved) {
            System.out.println("Failed to save history for tempId: " + tempId);
            return false;
        }

        System.out.println("Successfully processed tempId: " + tempId);
        return true;
    } catch (Exception e) {
        System.err.println("Error processing tempId: " + tempId + " - " + e.getMessage());
        e.printStackTrace();
        return false;
    }
}
	
	public List<Map<String, Object>> getPendencyUpdatingDuration(){
		
		String sqlQuery = "SELECT * FROM pensioner_details WHERE file_category IN (2,3) AND pending_duration='yes' AND file_status < 11";
	    List<Map<String, Object>> details = jdbcTemplate.queryForList(sqlQuery);
	    
	    return details;
    
	}
	
	public String calculatePendingDuration(LocalDate startDate, LocalDate endDate) {
        Period period = Period.between(startDate, endDate);

        int years = period.getYears();
        int months = period.getMonths();
        int days = period.getDays();
        
        if (years == 0 && months == 0 && days == 0) {
            return "0 days"; // or "Same day"
        }

        return (years > 0 ? years + " year " : "") +
               (months > 0 ? months + " month " : "") +
               (days > 0 ? days + " day" : "");
    }

    public boolean updatePendingDuration(String updateDuration, String tempId) {
        String sqlQuery = "UPDATE pensioner_details SET reason_for_pending=? WHERE temp_id=?";
        int rowsUpdated = jdbcTemplate.update(sqlQuery, updateDuration, tempId);
        System.out.println("Temp ID: " + tempId + " | Rows Updated: " + rowsUpdated);
        return rowsUpdated > 0;
    }

    // New method to get the count of pending pensioners
    public int getPendingPensionersCount() {
        String sqlQuery = "SELECT COUNT(*) FROM pensioner_details WHERE file_category=3 AND pending_duration='yes' AND file_status < 11";
        Integer count = jdbcTemplate.queryForObject(sqlQuery, Integer.class);
        return count != null ? count : 0;
    }
	

}