import { Project, ProjectMember, projects, projectMembers } from './db';
import { JwtUser } from './middleware/auth';

export function isOwner( project: Project, user: JwtUser ): boolean
{
  return project.owner_id === user.userId;
}

function memberMatchesUser( member: ProjectMember, user: JwtUser ): boolean
{
  if ( member.member_type !== 'user' ) return false;
  // Interim (Option B): member_id stores the email address.
  // When migrating to ID-based lookup, change this one line to: member.member_id === user.userId
  return member.member_id === user.email;
}

export function getMemberRole( members: ProjectMember[], user: JwtUser ): string | null
{
  return members.find( m => memberMatchesUser( m, user ) )?.role ?? null;
}

export function canView( project: Project, members: ProjectMember[], user: JwtUser ): boolean
{
  return isOwner( project, user ) || getMemberRole( members, user ) !== null;
}

export function canEdit( project: Project, members: ProjectMember[], user: JwtUser ): boolean
{
  if ( isOwner( project, user ) ) return true;
  const role = getMemberRole( members, user );
  return role === 'editor' || role === 'admin';
}

export interface AccessDenial { status: number; error: string; }

export function checkAccess( projectId: string, user: JwtUser, mode: 'view' | 'edit' ): AccessDenial | null
{
  const project = projects.findById( projectId );
  if ( !project ) return { status: 404, error: 'Not found' };
  const members = projectMembers.forProject( projectId );
  const allowed = mode === 'view' ? canView( project, members, user ) : canEdit( project, members, user );
  if ( !allowed ) return { status: 403, error: 'Forbidden' };
  return null;
}