import os = require('os');


/** 
 * Commands
 *
 * Command Format:
 *   ##[name key=value;key=value]message
 *   
 * Examples:
 *   ##[warning]This is the user warning message
 *   ##[set-secret name=mypassword]definatelyNotAPassword!
 */
export function _issueCommand(command: string, properties: any, message: string) {
    var cmd = new _Command(command, properties, message);
    _writeLine(cmd.toString());
}

export function _issue(name: string, message: string) {
    _issueCommand(name, {}, message);
}

let CMD_PREFIX = '##[';

export class _Command {
    constructor(command: string, properties: any, message: string) {
        if (!command) {
            command = 'missing.command';
        }

        this.command = command;
        this.properties = properties;
        this.message = message;
    }

    public command: string;
    public message: string;
    public properties: any;

    public toString() {
        var cmdStr = CMD_PREFIX + this.command;

        if (this.properties && Object.keys(this.properties).length > 0) {
            cmdStr += ' ';
            for (var key in this.properties) {
                if (this.properties.hasOwnProperty(key)) {
                    var val = this.properties[key];
                    if (val) {
                        // safely append the val - avoid blowing up when attempting to
                        // call .replace() if message is not a string for some reason
                        cmdStr += key + '=' + escape('' + (val || '')) + ';';
                    }
                }
            }
        }

        cmdStr += ']';

        // safely append the message - avoid blowing up when attempting to
        // call .replace() if message is not a string for some reason
        let message: string = '' + (this.message || '');
        cmdStr += escapedata(message);

        return cmdStr;
    }
}

export function _commandFromString(commandLine: string) {
    var preLen = CMD_PREFIX.length;
    var lbPos = commandLine.indexOf('[');
    var rbPos = commandLine.indexOf(']');
    if (lbPos == -1 || rbPos == -1 || rbPos - lbPos < 3) {
        throw new Error('Invalid command brackets');
    }
    var cmdInfo = commandLine.substring(lbPos + 1, rbPos);
    var spaceIdx = cmdInfo.indexOf(' ');

    var command = cmdInfo;
    var properties: {[key: string]: string} = {};

    if (spaceIdx > 0) {
        command = cmdInfo.trim().substring(0, spaceIdx);
        var propSection = cmdInfo.trim().substring(spaceIdx+1);

        var propLines: string[] = propSection.split(';');
        propLines.forEach(function (propLine: string) {
            propLine = propLine.trim();
            if (propLine.length > 0) {
                var eqIndex = propLine.indexOf('=');
                if (eqIndex == -1){
                    throw new Error('Invalid property: ' + propLine);
                }

                var key: string = propLine.substring(0, eqIndex);
                var val: string = propLine.substring(eqIndex+1);

                properties[key] = unescape(val);
            }
        });
    }

    let msg: string = unescapedata(commandLine.substring(rbPos + 1));
    var cmd = new _Command(command, properties, msg);
    return cmd;
}

function escapedata(s: string) : string {
    return s.replace(/\r/g, '%0D')
            .replace(/\n/g, '%0A');
}

function unescapedata(s: string) : string {
    return s.replace(/%0D/g, '\r')
            .replace(/%0A/g, '\n');
}

function escape(s: string) : string {
    return s.replace(/\r/g, '%0D')
            .replace(/\n/g, '%0A')
            .replace(/]/g, '%5D')
            .replace(/;/g, '%3B');
}

function unescape(s: string) : string {
    return s.replace(/%0D/g, '\r')
            .replace(/%0A/g, '\n')
            .replace(/%5D/g, ']')
            .replace(/%3B/g, ';');
}

//-----------------------------------------------------
// Streams: allow to override the stream
//-----------------------------------------------------

let _outStream = process.stdout;
let _errStream = process.stderr;

export function _writeLine(str: string): void {
    _outStream.write(str + os.EOL);
}

export function _setStdStream(stdStream: NodeJS.WriteStream): void {
    _outStream = stdStream;
}

export function _setErrStream(errStream: NodeJS.WriteStream): void {
    _errStream = errStream;
}