/**
 * OmniCard AI (CRMmp) - 无摩擦互换名片留资业务驱动层
 * 严格遵循 uts 强类型规范与 AGENTS.md 约束
 */

import { LeadEntity, SubmitLeadParams } from '../../common/types.uts';
import { submitLead } from '../../common/api.uts';

export type ExchangeForm = {
  name: string;
  company: string;
  phone: string;
  email: string;
  notes: string;
};

export type ExchangeState = {
  form: ExchangeForm;
  cardId: string;
  slug: string;
  submitting: boolean;
  canSubmit: boolean;
  errorMessage: string;
};

export type ExchangePageOptions = {
  cardId?: string;
  slug?: string;
  id?: string;
};

const VISITOR_STORAGE_KEY = 'omni_visitor_id';

/**
 * 读取本地已有访客标识，不在本页新建
 */
function readVisitorId(): string {
  try {
    const val = uni.getStorageSync(VISITOR_STORAGE_KEY);
    return val != null ? String(val) : '';
  } catch (e) {
    return '';
  }
}

/**
 * 创建互换名片表单初始状态
 */
export function createExchangeState(): ExchangeState {
  return {
    form: {
      name: '',
      company: '',
      phone: '',
      email: '',
      notes: '',
    },
    cardId: '',
    slug: '',
    submitting: false,
    canSubmit: false,
    errorMessage: '',
  };
}

/**
 * 解析提交用的名片标识：优先 cardId，其次 slug
 */
export function resolveExchangeCardId(state: ExchangeState): string {
  if (state.cardId && state.cardId.trim() !== '') {
    return state.cardId.trim();
  }
  if (state.slug && state.slug.trim() !== '') {
    return state.slug.trim();
  }
  return '';
}

/**
 * 从页面 onLoad options 写入名片标识
 * 缺少 cardId 与 slug 时 toast 并禁止提交
 */
export function applyExchangeOptions(
  state: ExchangeState,
  options: ExchangePageOptions | null
): boolean {
  const cardIdRaw = options != null ? options.cardId || options.id || '' : '';
  const slugRaw = options != null ? options.slug || '' : '';
  state.cardId = String(cardIdRaw).trim();
  state.slug = String(slugRaw).trim();
  state.canSubmit = resolveExchangeCardId(state) !== '';

  if (!state.canSubmit) {
    uni.showToast({
      title: '缺少名片标识，无法提交',
      icon: 'none',
    });
  }

  return state.canSubmit;
}

/**
 * 校验姓名 + (WhatsApp/phone 或 email)
 * 通过返回空字符串
 */
export function validateExchangeForm(form: ExchangeForm): string {
  const name = form.name ? form.name.trim() : '';
  if (name === '') {
    return '请填写姓名';
  }

  const phone = form.phone ? form.phone.trim() : '';
  const email = form.email ? form.email.trim() : '';
  if (phone === '' && email === '') {
    return '请填写 WhatsApp 或邮箱';
  }

  return '';
}

/**
 * 清空表单字段，保留名片标识
 */
export function resetExchangeForm(state: ExchangeState): void {
  state.form.name = '';
  state.form.company = '';
  state.form.phone = '';
  state.form.email = '';
  state.form.notes = '';
  state.errorMessage = '';
}

/**
 * 提交留资：校验通过后调用已有 submitLead
 */
export async function submitExchange(state: ExchangeState): Promise<LeadEntity | null> {
  const cardId = resolveExchangeCardId(state);
  if (!state.canSubmit || cardId === '') {
    uni.showToast({
      title: '缺少名片标识，无法提交',
      icon: 'none',
    });
    return null;
  }

  const invalidReason = validateExchangeForm(state.form);
  if (invalidReason !== '') {
    uni.showToast({
      title: invalidReason,
      icon: 'none',
    });
    return null;
  }

  if (state.submitting) {
    return null;
  }

  const name = state.form.name.trim();
  const company = state.form.company.trim();
  const phone = state.form.phone.trim();
  const email = state.form.email.trim();
  const notes = state.form.notes.trim();
  const visitorId = readVisitorId();

  const payload: SubmitLeadParams = {
    cardId,
    name,
  };
  if (company !== '') {
    payload.company = company;
  }
  if (phone !== '') {
    payload.phone = phone;
  }
  if (email !== '') {
    payload.email = email;
  }
  if (notes !== '') {
    payload.notes = notes;
  }
  if (visitorId !== '') {
    payload.visitorId = visitorId;
  }
  payload.source = 'link';

  state.submitting = true;
  state.errorMessage = '';

  try {
    const lead = await submitLead(payload);
    state.submitting = false;
    resetExchangeForm(state);
    uni.showToast({
      title: '留资已提交',
      icon: 'none',
    });
    return lead;
  } catch (err) {
    state.submitting = false;
    if (err instanceof Error) {
      state.errorMessage = err.message;
    } else {
      state.errorMessage = '提交留资失败';
    }
    return null;
  }
}