package com.example.demo.user;

import com.example.demo.attachment.AttachmentUrlValidator;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.security.crypto.bcrypt.BCrypt;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

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

@Service
public class UserService {

    private final JdbcTemplate jdbcTemplate;
    private final AttachmentUrlValidator urlValidator;

    public UserService(JdbcTemplate jdbcTemplate, AttachmentUrlValidator urlValidator) {
        this.jdbcTemplate = jdbcTemplate;
        this.urlValidator = urlValidator;
    }

    @Transactional(readOnly = true)
    public Map<String, Object> getProfile(Long userId) {
        return jdbcTemplate.query(
                con -> {
                    var ps = con.prepareStatement("SELECT id, shop_id, phone, email, name, avatar_url FROM users WHERE id=? LIMIT 1");
                    ps.setLong(1, userId);
                    return ps;
                },
                rs -> {
                    if (!rs.next()) return null;
                    Map<String, Object> m = new HashMap<>();
                    m.put("id", rs.getLong("id"));
                    m.put("shopId", rs.getLong("shop_id"));
                    m.put("phone", rs.getString("phone"));
                    m.put("email", rs.getString("email"));
                    m.put("name", rs.getString("name"));
                    m.put("avatarUrl", rs.getString("avatar_url"));
                    return m;
                }
        );
    }

    public static class UpdateProfileRequest { public String name; public String avatarUrl; }

    @Transactional
    public void updateProfile(Long userId, UpdateProfileRequest req) {
        if ((req.name == null || req.name.isBlank()) && (req.avatarUrl == null || req.avatarUrl.isBlank())) {
            return; // nothing to update
        }
        StringBuilder sql = new StringBuilder("UPDATE users SET ");
        java.util.List<Object> args = new java.util.ArrayList<>();
        boolean first = true;
        if (req.name != null) {
            String nm = req.name.trim();
            if (nm.isEmpty()) throw new IllegalArgumentException("姓名不能为空");
            if (nm.length() > 64) throw new IllegalArgumentException("姓名过长");
            sql.append(first ? "name=?" : ", name=?");
            args.add(nm);
            first = false;
        }
        if (req.avatarUrl != null) {
            String au = req.avatarUrl.trim();
            if (au.isEmpty()) {
                sql.append(first ? "avatar_url=NULL" : ", avatar_url=NULL");
            } else if (au.startsWith("/")) {
                String normalized = au.replaceAll("/{2,}", "/");
                sql.append(first ? "avatar_url=?" : ", avatar_url=?");
                args.add(normalized);
            } else {
                var vr = urlValidator.validate(au);
                sql.append(first ? "avatar_url=?" : ", avatar_url=?");
                args.add(vr.url());
            }
            first = false;
        }
        sql.append(", updated_at=NOW() WHERE id=?");
        args.add(userId);
        jdbcTemplate.update(sql.toString(), args.toArray());
    }

    public static class ChangePasswordRequest { public String oldPassword; public String newPassword; }

    @Transactional
    public void changePassword(Long userId, ChangePasswordRequest req) {
        if (req.newPassword == null || req.newPassword.isBlank()) throw new IllegalArgumentException("新密码不能为空");
        if (req.newPassword.length() < 6) throw new IllegalArgumentException("新密码至少6位");
        Map<String, Object> row = jdbcTemplate.query(
                con -> {
                    var ps = con.prepareStatement("SELECT password_hash FROM users WHERE id=?");
                    ps.setLong(1, userId);
                    return ps;
                },
                rs -> {
                    if (rs.next()) {
                        Map<String, Object> m = new HashMap<>();
                        m.put("password_hash", rs.getString(1));
                        return m;
                    }
                    return null;
                }
        );
        if (row == null) throw new IllegalArgumentException("用户不存在");
        String existing = (String) row.get("password_hash");
        if (existing != null && !existing.isBlank()) {
            if (req.oldPassword == null || req.oldPassword.isBlank()) throw new IllegalArgumentException("请提供旧密码");
            boolean ok = BCrypt.checkpw(req.oldPassword, existing);
            if (!ok) throw new IllegalArgumentException("旧密码不正确");
        }
        String newHash = BCrypt.hashpw(req.newPassword, BCrypt.gensalt());
        jdbcTemplate.update("UPDATE users SET password_hash=?, updated_at=NOW() WHERE id=?", newHash, userId);
    }

    public static class ChangePhoneRequest { public String phone; public String code; }

    @Transactional
    public void changePhone(Long userId, ChangePhoneRequest req) {
        ensurePhoneFormat(req.phone);
        // 无需验证码，直接保存；保留唯一性与格式校验
        try {
            jdbcTemplate.update("UPDATE users SET phone=?, updated_at=NOW() WHERE id=?", req.phone, userId);
        } catch (DataIntegrityViolationException e) {
            throw new IllegalArgumentException("该手机号已被占用");
        }
    }

    private void ensurePhoneFormat(String phone) {
        if (phone == null || phone.isBlank()) throw new IllegalArgumentException("手机号不能为空");
        String p = phone.replaceAll("\\s+", "");
        if (!p.matches("^1\\d{10}$")) throw new IllegalArgumentException("手机号格式不正确");
    }
}