package repository

import (
	"context"
	"errors"
	"time"

	"gorm.io/gorm"

	"github.com/dhao2001/mygo/internal/model"
)

// CredentialRepository provides access to alternative credential records.
type CredentialRepository interface {
	Create(ctx context.Context, cred *model.Credential) error
	FindByID(ctx context.Context, id string) (*model.Credential, error)
	FindByUserID(ctx context.Context, userID string) ([]model.Credential, error)
	FindByUserIDAndType(ctx context.Context, userID, credType string) ([]model.Credential, error)
	FindByHash(ctx context.Context, hash string) (*model.Credential, error)
	UpdateLastUsed(ctx context.Context, id string) error
	Delete(ctx context.Context, id string) error
}

type credentialRepository struct {
	db *gorm.DB
}

// NewCredentialRepository creates a CredentialRepository backed by GORM.
func NewCredentialRepository(db *gorm.DB) CredentialRepository {
	return &credentialRepository{db: db}
}

func (r *credentialRepository) Create(ctx context.Context, cred *model.Credential) error {
	result := r.db.WithContext(ctx).Create(cred)
	if result.Error != nil {
		if isDuplicateKeyError(result.Error) {
			return model.ErrDuplicate
		}
		return result.Error
	}
	return nil
}

func (r *credentialRepository) FindByID(ctx context.Context, id string) (*model.Credential, error) {
	var cred model.Credential
	result := r.db.WithContext(ctx).First(&cred, "id = ?", id)
	if errors.Is(result.Error, gorm.ErrRecordNotFound) {
		return nil, model.ErrNotFound
	}
	if result.Error != nil {
		return nil, result.Error
	}
	return &cred, nil
}

func (r *credentialRepository) FindByUserID(ctx context.Context, userID string) ([]model.Credential, error) {
	var creds []model.Credential
	result := r.db.WithContext(ctx).Where("user_id = ?", userID).Find(&creds)
	if result.Error != nil {
		return nil, result.Error
	}
	return creds, nil
}

func (r *credentialRepository) FindByUserIDAndType(ctx context.Context, userID, credType string) ([]model.Credential, error) {
	var creds []model.Credential
	result := r.db.WithContext(ctx).Where("user_id = ? AND type = ?", userID, credType).Find(&creds)
	if result.Error != nil {
		return nil, result.Error
	}
	return creds, nil
}

func (r *credentialRepository) FindByHash(ctx context.Context, hash string) (*model.Credential, error) {
	var cred model.Credential
	result := r.db.WithContext(ctx).First(&cred, "secret_hash = ?", hash)
	if errors.Is(result.Error, gorm.ErrRecordNotFound) {
		return nil, model.ErrNotFound
	}
	if result.Error != nil {
		return nil, result.Error
	}
	return &cred, nil
}

func (r *credentialRepository) UpdateLastUsed(ctx context.Context, id string) error {
	now := time.Now()
	result := r.db.WithContext(ctx).Model(&model.Credential{}).Where("id = ?", id).Update("last_used_at", now)
	if result.Error != nil {
		return result.Error
	}
	return nil
}

func (r *credentialRepository) Delete(ctx context.Context, id string) error {
	result := r.db.WithContext(ctx).Delete(&model.Credential{}, "id = ?", id)
	if result.Error != nil {
		return result.Error
	}
	return nil
}