<template>
  <div class="kole-idcard">
    <div class="kole-idcard-field" :class="{ 'is-focus': focused, 'is-valid': valid, 'is-invalid': invalid }">
      <input
        class="kole-idcard-input"
        :value="modelValue"
        maxlength="18"
        :placeholder="placeholder"
        @input="onInput"
        @focus="focused = true"
        @blur="focused = false"
      />
    </div>
    <div v-if="result.birth" class="kole-idcard-info">
      <span>出生日期：<b>{{ result.birth }}</b></span>
      <span>性别：<b>{{ result.gender }}</b></span>
    </div>
    <div class="kole-idcard-tip" :class="tipClass">{{ tipText }}</div>
  </div>
</template>

<script setup>
import { ref, computed } from 'vue';

const WEIGHTS = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2];
const CHECK = '10X98765432';
function validate(v) {
  if (!/^\d{17}[\dX]$/.test(v)) return null;
  let sum = 0;
  for (let i = 0; i < 17; i++) sum += parseInt(v[i], 10) * WEIGHTS[i];
  if (CHECK[sum % 11] !== v[17]) return null;
  const birth = v.slice(6, 14);
  return { birth: birth.slice(0, 4) + '-' + birth.slice(4, 6) + '-' + birth.slice(6, 8), gender: parseInt(v[16], 10) % 2 === 1 ? '男' : '女' };
}

const props = defineProps({
  modelValue: { type: String, default: '' },
  placeholder: { type: String, default: '请输入 18 位身份证号' }
});
const emit = defineEmits(['update:modelValue']);
const focused = ref(false);

const result = computed(() => validate(props.modelValue.toUpperCase()) || {});
const valid = computed(() => !!result.value.birth);
const invalid = computed(() => props.modelValue.length === 18 && !result.value.birth);
const tipClass = computed(() => (!props.modelValue ? '' : valid.value ? 'valid' : invalid.value ? 'invalid' : ''));
const tipText = computed(() => {
  if (!props.modelValue) return '示例：11010119900307657X';
  if (props.modelValue.length < 18) return '已输入 ' + props.modelValue.length + ' 位，继续…';
  return valid.value ? '校验通过' : '身份证号校验失败，请检查';
});

function onInput(e) {
  const v = e.target.value.replace(/[^0-9Xx]/g, '').toUpperCase().slice(0, 18);
  e.target.value = v;
  emit('update:modelValue', v);
}
</script>

<style src="./IDCardInput.css"></style>
