package repository

import (
	"context"
	"errors"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5"
	"github.com/travelswitch/travelhub/backend/internal/models"
)

// TenantBySlug resolves the tenant a caller is signing in to. Suspended
// tenants are treated as absent so their users cannot authenticate.
func (r *Repository) TenantBySlug(ctx context.Context, slug string) (models.Tenant, error) {
	const q = `
		SELECT id, slug, name, status, created_at
		FROM   tenants
		WHERE  slug = $1 AND status = 'active'`

	var t models.Tenant
	err := r.pool.QueryRow(ctx, q, slug).
		Scan(&t.ID, &t.Slug, &t.Name, &t.Status, &t.CreatedAt)
	if errors.Is(err, pgx.ErrNoRows) {
		return models.Tenant{}, ErrNotFound
	}
	return t, err
}

// ListTenants powers the tenant picker on the sign-in screen. It is the only
// unauthenticated read in the service and deliberately exposes nothing beyond
// the slug and display name.
func (r *Repository) ListTenants(ctx context.Context) ([]models.Tenant, error) {
	const q = `
		SELECT id, slug, name, status, created_at
		FROM   tenants
		WHERE  status = 'active'
		ORDER  BY name`

	rows, err := r.pool.Query(ctx, q)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	tenants := []models.Tenant{}
	for rows.Next() {
		var t models.Tenant
		if err := rows.Scan(&t.ID, &t.Slug, &t.Name, &t.Status, &t.CreatedAt); err != nil {
			return nil, err
		}
		tenants = append(tenants, t)
	}
	return tenants, rows.Err()
}

// UserByEmail looks up a login within one tenant. The tenant filter is what
// stops credentials from one agency authenticating against another.
func (r *Repository) UserByEmail(ctx context.Context, tenantID uuid.UUID, email string) (models.User, error) {
	const q = `
		SELECT id, tenant_id, email, password_hash, full_name, role, created_at
		FROM   users
		WHERE  tenant_id = $1 AND lower(email) = lower($2)`

	var u models.User
	err := r.pool.QueryRow(ctx, q, tenantID, email).Scan(
		&u.ID, &u.TenantID, &u.Email, &u.PasswordHash, &u.FullName, &u.Role, &u.CreatedAt,
	)
	if errors.Is(err, pgx.ErrNoRows) {
		return models.User{}, ErrNotFound
	}
	return u, err
}