<template>
  <el-input ref="input" :id="id" type="textarea" 
    :cols="cols"
    :rows="rows"
    v-bind="attrs"  v-bind:disabled="isDisable"
    :value="value"
    @input="onInput"
    >
    <template v-slot:suffix>
      <slot name="suffix"></slot>
    </template>
  </el-input>
</template>

<script>
const SP_STR = "✌";
const SP_CHAR=SP_STR.charCodeAt(0);
const LINE_CHAR="\n"
const SWIFT_CHARS = " \r'()+,-./01234567890:?ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
const SWIFTZ_CHARS = " \r!\"#%&'()+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz{";

const CHARSET = ["","",SWIFT_CHARS,SWIFTZ_CHARS]

export default {
  props: {
    value: {
      type: [String, Number],
      default: undefined
    },
    disabled: {
      type: Boolean,
      default: false
    },
    id: {
      type: String,
      default: undefined
    },
    cols:{
        type:Number,
        default:1
    },
    rows:{
        type:Number,
        default:1
    },
    chsbit:{
      type:Number,
      default:2
    },
    charmod:{
      type:Number,
      default:0   //0任意模式，1英文模式，2 swift模式 3 swiftz模式
    }
  },
  computed: {
    
    mode () {
      return this.$store.state.Status.mode
    },
    isDisable: {
      get () {
        return this.mode === 'display' || this.disabled
      }
    },
    highlight () {
      return this.$store.state.Status.highlights.indexOf(this.id) !== -1
    },
    highlightChanges () {
      return this.$store.state.Status.highlightChanges.indexOf(this.id) !== -1
    },
    attrs(){
      if(this.mode === 'display' || this.disabled)
      {
        let {placeholder,...rest} = this.$attrs
        return rest
      }
      return this.$attrs
    }
  },
  methods:{
    formatVal(oriVal){
        let val = oriVal;
        if(!val){
            return val;
        }
        let position = this.getCursorPosition();
        val = val.substring(0,position)+SP_STR+val.substring(position)
        let arr = val.split(/\r?\n|\r/g);
        let arrNew = [];
        arr.forEach(line=>{
            let lineArr = this.formatLine(line);
            arrNew.push(...lineArr);
        });
        if(arrNew.length > this.rows){
            let obj = this.getTextarea();
            //内容已经输满了
            if(obj.selectionStart == obj.selectionEnd && oriVal.length == this.value.length+1){
              this.$position = position - 1;
              return this.value;
            }
            arrNew = arrNew.slice(0,this.rows);
        }
        let result = arrNew.join(LINE_CHAR);
        position = result.indexOf(SP_STR);
        result = result.substring(0,position)+result.substring(position+1);
        this.$position = position
        return result;
    },
    formatLine(val){
        if(!val){
            return [""];
        }
        if(val == SP_STR){
          return [SP_STR]
        }
        let valCopy = val;
        let newVal = [];
        while(valCopy && valCopy!=SP_STR){
            let length = 0;
            let i=0;
            let spCnt =0;
            let autoLine = "";
            for(; i<valCopy.length && i<this.cols+spCnt && length<this.cols; i++) {
              var c = valCopy.charCodeAt(i);
              let cStr = valCopy.charAt(i);
              if(c == SP_CHAR){
                spCnt++;
                autoLine+=SP_STR;
                continue;
              }
              else if ((c >= 0x0001 && c <= 0x007e) || ( c >= 0xff60 && c <= 0xff9f )){ 
                //判断字符集
                if(this.charmod>1 && CHARSET[this.charmod].indexOf(cStr)==-1){
                  spCnt++;
                  //非法字符集
                  continue;
                }
                length ++;
                autoLine+=cStr;
                
              }
              else if(length <= this.cols - this.chsbit){
                //中文字符
               if(this.charmod){
                  spCnt++;
                  //非法字符集
                  continue;
               }
                length += this.chsbit;
                autoLine+=cStr;
              }
              else{
                break;
              }
            }
            //autoLine = valCopy.substring(0,i);
            newVal.push(autoLine);
            valCopy = valCopy.substring(i);
        }
        //不要丢失光标
        if(valCopy == SP_STR){
          newVal[newVal.length - 1] = newVal[newVal.length - 1]+SP_STR;
        }
        return newVal;
    },
    getTextarea(){
      return this.$refs.input.$el.children[0];
    },
    getCursorPosition(){
        let obj = this.getTextarea();
        let position = obj.selectionStart
        return position;
    },
    setCursorPosition(position){
      let obj = this.getTextarea();
      if(obj.createTextRange) {
        var tr = obj.createTextRange();
        tr.collapse(true);
        tr.moveStart('character', position);
        tr.select();
      }
      else if (obj.setSelectionRange)
        obj.setSelectionRange(position, position);
    },
    onInput(newVal){
       let extraCnt = 0;
        if(this.value && newVal.length == this.value.length -1 ){
          let obj = this.getTextarea();
          if(obj.selectionStart == obj.selectionEnd && obj.selectionStart<newVal.length && this.value.charAt(obj.selectionStart)=="\n"){
            //删除中间换行符，额外再筛除一个字符，避免被重新格式化
            newVal = newVal.substring(0,obj.selectionStart - 1)+newVal.substring(obj.selectionStart)
            extraCnt = -2;
          }
        }
        newVal = this.formatVal(newVal);
        console.log(newVal)
        this.$emitNewValue = newVal;
        this.$emit('input', newVal)
        setTimeout(()=>{
         this.setCursorPosition(this.$position+extraCnt)   
        },0)
    }
  },
  watch:{
    cols(){
      let newVal = this.formatVal(this.value);
      this.$emitNewValue = newVal;
      this.$emit('input', newVal)
    },
    rows(){
      let newVal = this.formatVal(this.value);
      this.$emitNewValue = newVal;
      this.$emit('input', newVal)
    },
    value(val,oldval){
      if(val == this.$emitNewValue){
        return;
      }
      let newVal = this.formatVal(val);
      this.$emit('input', newVal);
    }
  }
}
</script>

<style>
/* .el-input.highlight .el-input__inner{
  border-color: red;
}
.el-textarea.highlight .el-textarea__inner {
  border-color: red;
}
.el-input.change-light .el-input__inner{
  border-color: #E6A23C;
}
.el-textarea.change-light .el-textarea__inner {
  border-color: #E6A23C;
} */
</style>