package auth

import (
	"context"
	"errors"
	"time"

	"hfb_sys/backend/internal/model"

	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

type UserRepository struct {
	db *gorm.DB
}

func NewUserRepository(db *gorm.DB) *UserRepository {
	return &UserRepository{db: db}
}

func (r *UserRepository) FindByID(ctx context.Context, id uint64) (*model.User, error) {
	var user model.User
	if err := r.db.WithContext(ctx).First(&user, id).Error; err != nil {
		return nil, err
	}
	return &user, nil
}

// FindActiveForToken 校验用户仍可用且令牌版本未被撤销。
func (r *UserRepository) FindActiveForToken(ctx context.Context, id uint64, tokenVersion int64) (*model.User, error) {
	if r == nil || r.db == nil {
		return nil, ErrDependencyUnavailable
	}
	user, err := r.FindByID(ctx, id)
	if err != nil {
		return nil, err
	}
	if user.Status != "active" || user.TokenVersion <= 0 || user.TokenVersion != tokenVersion {
		return nil, ErrUserDisabled
	}
	return user, nil
}

func (r *UserRepository) UpdateProfile(ctx context.Context, id uint64, nickname string, avatarURL string) (*model.User, error) {
	if err := r.db.WithContext(ctx).Model(&model.User{}).Where("id = ?", id).Updates(map[string]any{
		"nickname":   nickname,
		"avatar_url": avatarURL,
	}).Error; err != nil {
		return nil, err
	}
	return r.FindByID(ctx, id)
}

func (r *UserRepository) FindOrCreateByPhone(ctx context.Context, phone string) (*model.User, error) {
	now := time.Now()
	user := model.User{
		Phone:          phone,
		Nickname:       "用户" + phone[len(phone)-4:],
		RealnameStatus: "unverified",
		RiskStatus:     "normal",
		CreditScore:    100,
		Status:         "active",
		TokenVersion:   1,
		LastLoginAt:    &now,
	}

	err := r.db.WithContext(ctx).Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "phone"}},
		DoUpdates: clause.AssignmentColumns([]string{"last_login_at", "updated_at"}),
	}).Create(&user).Error
	if err != nil {
		return nil, err
	}

	var found model.User
	if err := r.db.WithContext(ctx).Where("phone = ?", phone).First(&found).Error; err != nil {
		return nil, err
	}
	return &found, nil
}

func (r *UserRepository) FindByPhone(ctx context.Context, phone string) (*model.User, error) {
	var user model.User
	if err := r.db.WithContext(ctx).Where("phone = ?", phone).First(&user).Error; err != nil {
		return nil, err
	}
	return &user, nil
}

func (r *UserRepository) SetPassword(ctx context.Context, userID uint64, hash string) error {
	return r.db.WithContext(ctx).Model(&model.User{}).Where("id = ?", userID).Updates(map[string]any{
		"password_hash": hash,
		"token_version": gorm.Expr("token_version + 1"),
	}).Error
}

// RevokeTokens 使当前用户的所有 access/refresh token 立即失效。
func (r *UserRepository) RevokeTokens(ctx context.Context, userID uint64) error {
	return r.db.WithContext(ctx).Model(&model.User{}).Where("id = ?", userID).
		UpdateColumn("token_version", gorm.Expr("token_version + 1")).Error
}

func (r *UserRepository) RegisterWithPassword(ctx context.Context, phone string, hash string) (*model.User, error) {
	now := time.Now()
	user := model.User{
		Phone:          phone,
		PasswordHash:   hash,
		Nickname:       "用户" + phone[len(phone)-4:],
		RealnameStatus: "unverified",
		RiskStatus:     "normal",
		CreditScore:    100,
		Status:         "active",
		TokenVersion:   1,
		LastLoginAt:    &now,
	}

	err := r.db.WithContext(ctx).Create(&user).Error
	if err != nil {
		return nil, err
	}
	return &user, nil
}

func IsNotFound(err error) bool {
	return errors.Is(err, gorm.ErrRecordNotFound)
}