import SScript from "./SScript";
import Label = Laya.Label;

export default class SLabel extends SScript{
    static PLACE_HOLDER_REG = new RegExp('{[0-9]}', 'g');

    /** @prop {name:useEllipsis, tips:"是否在文本长度超出宽度后显示省略号", type:bool} */
    useEllipsis:boolean = false;
    /** @prop {name:ellipsisString, tips:"省略号字符串，默认为'...''", type:string} */
    ellipsisString:string = '...';
    /** @prop {name:usePlaceholder, tips:"是否使用占位符，一旦使用占位符后，对宿主Label的text设置就只会影响占位符部分，设置text时每个占位符字符串之间需要以'|'符号进行分隔。占位符为{n}的形式，n是从1开始的递增索引号。", type:bool} */
    usePlaceholder:boolean = false;
    /** @prop {name:defaultPlaceHolderString, tips:"占位符默认文本", type:string} */
    defaultPlaceHolderString:string;

    protected $label:Label;

    private _originalStr:string;

    onAwake(){
        if(this.owner instanceof Label)
        {
            this.$label = this.owner;
            if(this.useEllipsis){
                this.$label.overflow = Laya.Text.HIDDEN;
                //Laya.Text的_parseLine方法可以计算出最终需要渲染的字符串有哪些
                let overrideFucName = '_parseLine';
                let overrideTarget = this.$label['_tf'];
                let origiFuc = overrideTarget[overrideFucName];
                let ellipsisString = this.ellipsisString;
                //重载_parseLine方法并在执行其原始方法后修改最终需要渲染的字符串
                overrideTarget[overrideFucName] = function(line){
                    origiFuc.apply(this, arguments);
                    //最终将渲染的字符串均存于_lines数组中，修改其最后一行字符串的最后几个字为省略号即可
                    let lastLine:string = this._lines[this._lines.length - 1];
                    if(lastLine && (line != lastLine)){
                        for(let i = 1; i < lastLine.length; i++)
                        {
                            let tempStr = lastLine.substr(lastLine.length - i);
                            if(this._getTextWidth(tempStr) > this._getTextWidth(ellipsisString))
                            {
                                lastLine = lastLine.substring(0, lastLine.length - i) + ellipsisString;
                                break;
                            }
                        }
                        this._lines[this._lines.length - 1] = lastLine;
                    }
                };
            }

            if(this.usePlaceholder)
            {
                this.$label['textFilter'] = (value)=>{
                    if(this._originalStr)
                    {
                        value = value ? value + '' : '';
                        let ary = value.split('|');
                        value = this._originalStr;
                        let match = this._originalStr.match(SLabel.PLACE_HOLDER_REG);
                        for(let i = 0; i < ary.length; i++)
                        {
                            if(match[i])
                            {
                                value = value.replace(match[i], ary[i]);
                            }
                        }
                    }
                    return value;
                }
                let origiText = this.$label.text;
                //测试起始状态宿主text属性中是否含有占位符，若有，则将此时的text存起来
                if(origiText.match(SLabel.PLACE_HOLDER_REG))
                {
                    this._originalStr = origiText;
                    if(this.defaultPlaceHolderString)this.$label.text = this.defaultPlaceHolderString;
                }
            }
        }
        else
        {
            console.error('请保证SLabel的宿主是Label类型');
        }
    }
}