export const menuReducer = (state, action) => {
  switch (action) {
    case 'show': return true;
    case 'hide': return false;
    case 'toggle': return !state;
    default: throw new Error("menustate unknown to reducer");
  }
}

export const sessionReducer = (state, action) => {
  switch (action.type) {
    case 'start': return { active: true, token: action.token, username: action.username }
    case 'end': return { active: false, token: null, username: null, exiry: null }
    default: throw new Error("action type unknown to session reducer");
  }
}

export const userTableReducer = (state, action) => {
  let user = action.user;
  switch (action.type) {
    case 'create': return [...state, { line: state.length, ...user }];
    case 'delete': {
      let newstate = [];
      let newindex = 0;
      state.forEach((u, i) => {
        if (user.uid && u.uid != user.uid || user.line && i != user.line)
          newstate.push({ ...u, line: newindex++ })
        return newstate;
      }, []);
      return newstate;
    }
    case 'update': {
      let newstate = [];
      state.forEach((u, i) => {
        if (user.uid && u.uid == user.uid || user.line && i == user.line)
          newstate.push(user);
        else
          newstate.push(u);
      });
      return [...newstate]
    }
    case 'import':
      return action.imported;
    case 'reset':
      return [];
    default:
      throw new Error("action type unknown to usertable reducer");
  }
}