import { Pipe, PipeTransform } from '@angular/core';

/*
 * Transforms text containing URLs or E-mails to valid links/mailtos
*/
@Pipe({name: 'linkfy'})
export class LinkfyPipe implements PipeTransform {
    transform(message: string, pipeEnabled: boolean): string {
        if (pipeEnabled && message && message.length > 1)
        {
            let replacedText;
            let replacePatternProtocol;
            let replacePatternWWW;
            let replacePatternMailTo;

            // URLs starting with http://, https://, or ftp://
            replacePatternProtocol = /(\b(https?|ftp):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/gim;
            replacedText = message.replace(replacePatternProtocol, '<a href="$1" target="_blank">$1</a>');

            // URLs starting with "www." (ignoring // before it).
            replacePatternWWW = /(^|[^\/])(www\.[\S]+(\b|$))/gim;
            replacedText = replacedText.replace(replacePatternWWW, '$1<a href="http://$2" target="_blank">$2</a>');

            // Change email addresses to mailto:: links.
            replacePatternMailTo = /(([a-zA-Z0-9\-\_\.])+@[a-zA-Z\_]+?(\.[a-zA-Z]{2,6})+)/gim;
            replacedText = replacedText.replace(replacePatternMailTo, '<a href="mailto:$1">$1</a>');

            return replacedText;
        }
        else
            return message;
    } 
}