node-metaverse/tools/writePacketClasses.js

const messages = require('./msg_template.json');
const path = require('path');
const fs = require('fs');

messages.forEach((message) =>
{
    let classString = '// This file has been automatically generated by writePacketClasses.js\n\n';

    //First import required classes
    let uuid = false;
    let ipaddr = false;
    let vector3 = false;
    let vector4 = false;
    let long = false;
    let quaternion = false;
    message.blocks.forEach((block) =>
    {
        block.params.forEach((param) =>
        {
            switch(param.type)
            {
                case 'BOOL':
                case 'U32':
                case 'S32':
                case 'S8':
                case 'U8':
                case 'U16':
                case 'S16':
                case 'F32':
                case 'F64':
                case "IPPORT":
                case "Fixed":
                case 'Variable':
                    break;
                case "LLVector3d":
                    vector3 = true;
                    break;
                case "LLVector3":
                    vector3 = true;
                    break;
                case "LLVector4":
                    vector4 = true;
                    break;
                case "LLQuaternion":
                    quaternion = true;
                    break;
                case "LLUUID":
                    uuid = true;
                    break;
                case "IPADDR":
                    ipaddr = true;
                    break;
                case "U64":
                    long = true;
                    break;
                default:
                    console.log("UNKNOWN TYPE: "+param.type);
            }
        });
    });
    if (uuid)
    {
        classString += 'import {UUID} from \'../UUID\';\n'
    }
    if (ipaddr)
    {
        classString += 'import {IPAddress} from \'../IPAddress\';\n'
    }
    if (vector3)
    {
        classString += 'import {Vector3} from \'../Vector3\';\n'
    }
    if (vector4)
    {
        classString += 'import {Vector4} from \'../Vector4\';\n'
    }
    if (long)
    {
        classString += 'import Long = require(\'long\');\n'
    }
    if (quaternion)
    {
        classString += 'import {Quaternion} from \'../Quaternion\';\n'
    }
    classString += 'import {MessageFlags} from \'../../enums/MessageFlags\';\n' +
        'import {Packet} from \'../Packet\';\n\n';

    classString += 'export class ' + message.name + 'Packet implements Packet\n';
    classString += '{\n';
    classString += '    name = \''+message.name+'\';\n';


    var flags = [];
    message.flags.forEach((flag) =>
    {
       switch(flag.toUpperCase())
       {
           case 'TRUSTED':
               flags.push('MessageFlags.Trusted');
               break;
           case 'UDPDEPRECATED':
           case 'DEPRECATED':
               flags.push('MessageFlags.Deprecated');
               break;
           case 'ZEROCODED':
               flags.push('MessageFlags.Zerocoded');
               break;
           case 'UNENCODED':
               break;
           case 'NOTTRUSTED':
               break;
           case 'UDPBLACKLISTED':
               flags.push('MessageFlags.Blacklisted');
               break;
           default:
               console.log("UNKNOWN FLAG: "+flag);
               break;

       }
    });
    let id = parseInt(message.id);
    switch(message.frequency)
    {
        case 'Low':
            id += 4294901760;
            flags.push('MessageFlags.FrequencyLow');
            break;
        case 'Medium':
            id += 65280;
            flags.push('MessageFlags.FrequencyMedium');
            break;
        case 'Fixed':
            flags.push('MessageFlags.FrequencyFixed');
            break;
        case 'High':
            flags.push('MessageFlags.FrequencyHigh');
            break;
        default:
            console.log("UNKNOWN FREQUENCY: "+message.frequency);
            break;
    }
    classString += '    flags = ' + flags.join(' | ')+';\n';




    classString += '    id = ' + id+';\n';
    classString += '\n';

    let messageFixedSize = 0;
    let messageVariableSize = [];
    let calcVarVar = false;

    message.blocks.forEach((block) =>
    {
        classString += '    '+block.name+': {\n';

        let blockFixedSize = 0;
        let blockVariableSize = [];


        block.params.forEach((param) =>
        {
            classString += '        '+param.name+': ';
            let jstype = 'string';
            switch(param.type)
            {
                case 'LLUUID':
                    jstype = 'UUID';
                    blockFixedSize += 16;
                    break;
                case 'F32':
                case 'S32':
                case 'U32':
                    blockFixedSize += 4;
                    jstype = 'number';
                    break;
                case 'IPPORT':
                case 'S16':
                case 'U16':
                    blockFixedSize += 2;
                    jstype = 'number';
                    break;
                case 'U64':
                case 'S64':
                    jstype = 'Long';
                    blockFixedSize += 8;
                    break;
                case 'F64':
                    blockFixedSize += 8;
                    jstype = 'number';
                    break;
                case 'S8':
                case 'U8':
                    blockFixedSize += 1;
                    jstype = 'number';
                    break;
                case 'BOOL':
                    blockFixedSize += 1;
                    jstype = 'boolean';
                    break;
                case 'Variable':
                    jstype = 'string';

                    if (block.type === 'Single')
                    {
                        blockVariableSize.push('this.' + block.name + '[\'' + param.name + '\'].length + ' + param.size);
                    }
                    else
                    {
                        //Variable parameter in variable or multi block - tricky edge case
                        blockVariableSize.push('this.calculateVarVarSize(this.'+block.name+', \''+param.name+'\', '+param.size+')')
                        calcVarVar = true;
                    }
                    break;
                case 'LLVector4':
                    blockFixedSize += 16;
                    jstype = 'Vector4';
                    break;
                case 'LLQuaternion':
                    // because it's always a unit quaternion, transmitted in messages as a triplet of floats, 12 bytes wide (represented in memory as a quad of floats, 16 bytes wide)
                    blockFixedSize += 12;
                    jstype = 'Quaternion';
                    break;
                case 'LLVector3d':
                    blockFixedSize += 24;
                    jstype = 'Vector3';
                    break;
                case 'LLVector3':
                    blockFixedSize += 12;
                    jstype = 'Vector3';
                    break;
                case 'IPADDR':
                    blockFixedSize += 4;
                    jstype = 'IPAddress';
                    break;
                case 'Fixed':
                    blockFixedSize += parseInt(param.size);
                    jstype = 'Buffer';
                    break;
                default:
                    console.log('Unknown type: '+param.type);
            }
            classString += jstype + ';\n';
        });

        if (block.type === 'Single')
        {
            messageFixedSize += blockFixedSize;
            if (blockVariableSize.length > 0)
            {
                messageVariableSize.push('(' + blockVariableSize.join(' + ') + ')');
            }
        }
        else if (block.type === 'Multiple')
        {
            messageFixedSize += blockFixedSize * block.count;
            if (blockVariableSize.length > 0)
            {
                messageVariableSize.push('((' + blockVariableSize.join(' + ') + ') * ' + block.count + ')');
            }
        }
        else if (block.type === 'Variable')
        {
            messageFixedSize += 1; //variable block starts with a U8
            if (blockFixedSize > 0)
            {
                blockVariableSize.push(blockFixedSize);
            }
            if (blockVariableSize.length > 0)
            {
                messageVariableSize.push('((' + blockVariableSize.join(' + ') + ') * this.' + block.name + '.length)');
            }
        }

        switch(block.type)
        {
            case 'Single':
                classString += '    };\n';
                break;
            case 'Variable':
            case 'Multiple':
                classString += '    }[];\n';

                break;
            default:
                console.log("Unknown type: "+block.type);
        }
    });

    classString+='\n';
    classString+='    getSize(): number\n';
    classString+='    {\n';
    if (messageFixedSize > 0)
    {
        messageVariableSize.push(messageFixedSize);
    }
    if (messageVariableSize.length === 0)
    {
        classString += '        return 0;\n';
    }
    else
    {
        classString += '        return ' + messageVariableSize.join(' + ') + ';\n';
    }
    classString+='    }\n';
    classString+='\n';
    if (calcVarVar)
    {
        classString+='    calculateVarVarSize(block: object[], paramName: string, extraPerVar: number): number\n' +
            '    {\n' +
            '        let size = 0;\n' +
            '        block.forEach((bl: any) =>\n' +
            '        {\n' +
            '            size += bl[paramName].length + extraPerVar;\n' +
            '        });\n' +
            '        return size;\n' +
            '    }\n\n';
    }

    classString += '}\n';

    const p = path.join(__dirname+'/../lib/classes/packets/'+message.name+'.ts');
    fs.writeFile(p, classString, (err) =>
    {

    });

});