mlnet.js

// Experimental

import * as base from './base.js';

const mlnet = {};

mlnet.ModelFactory = class {

    async match(context) {
        const entries = await context.peek('zip');
        if (entries instanceof Map && entries.size > 0) {
            const root = new Set(['TransformerChain', 'Predictor']);
            if (Array.from(entries.keys()).some((name) => root.has(name.split('\\').shift().split('/').shift()))) {
                return context.set('mlnet', entries);
            }
        }
        return null;
    }

    async open(context) {
        const metadata = await context.metadata('mlnet-metadata.json');
        const reader = new mlnet.ModelReader(context.value);
        await reader.resolve(context);
        return new mlnet.Model(metadata, reader);
    }
};

mlnet.Model = class {

    constructor(metadata, reader) {
        this.format = "ML.NET";
        if (reader.version && reader.version.length > 0) {
            this.format += ` v${reader.version}`;
        }
        this.modules = [new mlnet.Module(metadata, reader)];
    }
};

mlnet.Module = class {

    constructor(metadata, reader) {
        this.inputs = [];
        this.outputs = [];
        this.nodes = [];
        this.groups = false;
        const values = new Map();
        values.map = (name, type) => {
            if (!values.has(name)) {
                values.set(name, new mlnet.Value(name, type || null));
            } else if (type) {
                throw new mlnet.Error(`Duplicate value '${name}'.`);
            }
            return values.get(name);
        };
        if (reader.schema && reader.schema.inputs) {
            for (const input of reader.schema.inputs) {
                const argument = new mlnet.Argument(input.name, [values.map(input.name, new mlnet.TensorType(input.type))]);
                this.inputs.push(argument);
            }
        }
        const createNode = (scope, group, transformer) => {
            if (transformer.inputs && transformer.outputs) {
                for (const input of transformer.inputs) {
                    input.name = scope[input.name] ? scope[input.name].argument : input.name;
                }
                for (const output of transformer.outputs) {
                    if (scope[output.name]) {
                        scope[output.name].counter++;
                        const next = `${output.name}\n${scope[output.name].counter}`; // custom argument id
                        scope[output.name].argument = next;
                        output.name = next;
                    } else {
                        scope[output.name] = {
                            argument: output.name,
                            counter: 0
                        };
                    }
                }
            }
            const node = new mlnet.Node(metadata, transformer, group, values);
            this.nodes.push(node);
        };
        /* eslint-disable no-use-before-define */
        const loadChain = (scope, name, chain) => {
            this.groups = true;
            const group = name.split('/').splice(1).join('/');
            for (const childTransformer of chain) {
                loadTransformer(scope, group, childTransformer);
            }
        };
        const loadTransformer = (scope, group, transformer) => {
            switch (transformer.__type__) {
                case 'TransformerChain':
                case 'Text':
                    loadChain(scope, transformer.__name__, transformer.chain);
                    break;
                default:
                    createNode(scope, group, transformer);
                    break;
            }
        };
        const scope = new Map();
        if (reader.schema && reader.schema.inputs) {
            for (const input of reader.schema.inputs) {
                scope[input.name] = { argument: input.name, counter: 0 };
            }
        }
        if (reader.dataLoaderModel) {
            loadTransformer(scope, '', reader.dataLoaderModel);
        }
        if (reader.predictor) {
            loadTransformer(scope, '', reader.predictor);
        }
        if (reader.transformerChain) {
            loadTransformer(scope, '', reader.transformerChain);
        }
    }
};

mlnet.Argument = class {

    constructor(name, value, type = null) {
        this.name = name;
        this.value = value;
        this.type = type;
    }
};

mlnet.Value = class {

    constructor(name, type) {
        if (typeof name !== 'string') {
            throw new mlnet.Error(`Invalid value identifier '${JSON.stringify(name)}'.`);
        }
        this.name = name;
        this.type = type;
        this.initializer = null;
    }
};

mlnet.Node = class {

    constructor(metadata, obj, group, values) {
        const op = obj.__type__;
        this.type = metadata.type(op) || { name: op || '?' };
        this.name = obj.__name__ || '';
        this.group = group || '';
        this.inputs = [];
        this.outputs = [];
        this.attributes = [];
        if (values && obj.inputs) {
            for (let i = 0; i < obj.inputs.length; i++) {
                const value = values.map(obj.inputs[i].name);
                this.inputs.push(new mlnet.Argument(i.toString(), [value]));
            }
        }
        if (values && obj.outputs) {
            for (let i = 0; i < obj.outputs.length; i++) {
                this.outputs.push(new mlnet.Argument(i.toString(), [values.map(obj.outputs[i].name)]));
            }
        }
        for (const [name, raw] of Object.entries(obj).filter(([key]) => !key.startsWith('_') && key !== 'inputs' && key !== 'outputs')) {
            const schema = metadata.attribute(op, name);
            let value = raw;
            let type = null;
            if (schema) {
                type = schema.type ? schema.type : null;
                value = mlnet.Utility.enum(type, value);
            }
            if (value && typeof value === 'object' && !Array.isArray(value) && Array.isArray(value.nodes)) {
                type = 'graph';
            } else if (value && typeof value === 'object' && !Array.isArray(value) && value.__type__) {
                value = new mlnet.Node(metadata, value);
                type = 'object';
            } else if (Array.isArray(value) && value.length > 0 && value.every((item) => item && item.__type__)) {
                value = value.map((item) => new mlnet.Node(metadata, item));
                type = 'object[]';
            }
            this.attributes.push(new mlnet.Argument(name, value, type));
        }
    }
};

mlnet.TensorType = class {

    constructor(codec) {
        mlnet.TensorType._map = mlnet.TensorType._map || new Map([
            ['Byte', 'uint8'],
            ['Boolean', 'boolean'],
            ['Single', 'float32'],
            ['Double', 'float64'],
            ['UInt32', 'uint32'],
            ['Int32', 'int32'],
            ['Int64', 'int64'],
            ['TextSpan', 'string']
        ]);
        this.dataType = '?';
        this.shape = new mlnet.TensorShape(null);
        if (mlnet.TensorType._map.has(codec.name)) {
            this.dataType = mlnet.TensorType._map.get(codec.name);
        } else if (codec.name === 'VBuffer') {
            if (mlnet.TensorType._map.has(codec.itemType.name)) {
                this.dataType = mlnet.TensorType._map.get(codec.itemType.name);
            } else {
                throw new mlnet.Error(`Unsupported data type '${codec.itemType.name}'.`);
            }
            this.shape = new mlnet.TensorShape(codec.dims);
        } else if (codec.name === 'Key2') {
            this.dataType = 'key2';
        } else {
            throw new mlnet.Error(`Unsupported data type '${codec.name}'.`);
        }
    }

    toString() {
        return this.dataType + this.shape.toString();
    }
};

mlnet.TensorShape = class {

    constructor(dimensions) {
        this.dimensions = dimensions;
    }

    toString() {
        if (!this.dimensions || this.dimensions.length === 0) {
            return '';
        }
        return `[${this.dimensions.join(',')}]`;
    }
};

mlnet.ModelReader = class {

    constructor(entries) {
        const catalog = new mlnet.ComponentCatalog();
        catalog.register('AffineNormExec', mlnet.AffineNormSerializationUtils);
        catalog.register('AnomalyPredXfer', mlnet.AnomalyPredictionTransformer);
        catalog.register('BinaryPredXfer', mlnet.BinaryPredictionTransformer);
        catalog.register('BinaryLoader', mlnet.BinaryLoader);
        catalog.register('CaliPredExec', mlnet.CalibratedPredictor);
        catalog.register('CdfNormalizeFunction', mlnet.CdfColumnFunction);
        catalog.register('CharToken', mlnet.TokenizingByCharactersTransformer);
        catalog.register('ChooseColumnsTransform', mlnet.ColumnSelectingTransformer);
        catalog.register('ClusteringPredXfer', mlnet.ClusteringPredictionTransformer);
        catalog.register('ConcatTransform', mlnet.ColumnConcatenatingTransformer);
        catalog.register('CopyTransform', mlnet.ColumnCopyingTransformer);
        catalog.register('ConvertTransform', mlnet.TypeConvertingTransformer);
        catalog.register('CSharpTransform', mlnet.CSharpTransform);
        catalog.register('DropColumnsTransform', mlnet.DropColumnsTransform);
        catalog.register('FAFMPredXfer', mlnet.FieldAwareFactorizationMachinePredictionTransformer);
        catalog.register('FastForestBinaryExec', mlnet.FastForestClassificationPredictor);
        catalog.register('FastTreeBinaryExec', mlnet.FastTreeBinaryModelParameters);
        catalog.register('FastTreeTweedieExec', mlnet.FastTreeTweedieModelParameters);
        catalog.register('FastTreeRankerExec', mlnet.FastTreeRankingModelParameters);
        catalog.register('FastTreeRegressionExec', mlnet.FastTreeRegressionModelParameters);
        catalog.register('FeatWCaliPredExec', mlnet.FeatureWeightsCalibratedModelParameters);
        catalog.register('FieldAwareFactMacPredict', mlnet.FieldAwareFactorizationMachineModelParameters);
        catalog.register('GcnTransform', mlnet.LpNormNormalizingTransformer);
        catalog.register('GenericScoreTransform', mlnet.GenericScoreTransform);
        catalog.register('IidChangePointDetector', mlnet.IidChangePointDetector);
        catalog.register('IidSpikeDetector', mlnet.IidSpikeDetector);
        catalog.register('ImageClassificationTrans', mlnet.ImageClassificationTransformer);
        catalog.register('ImageClassificationPred', mlnet.ImageClassificationModelParameters);
        catalog.register('ImageLoaderTransform', mlnet.ImageLoadingTransformer);
        catalog.register('ImageScalerTransform', mlnet.ImageResizingTransformer);
        catalog.register('ImagePixelExtractor', mlnet.ImagePixelExtractingTransformer);
        catalog.register('KeyToValueTransform', mlnet.KeyToValueMappingTransformer);
        catalog.register('KeyToVectorTransform', mlnet.KeyToVectorMappingTransformer);
        catalog.register('KMeansPredictor', mlnet.KMeansModelParameters);
        catalog.register('LinearRegressionExec', mlnet.LinearRegressionModelParameters);
        catalog.register('LightGBMRegressionExec', mlnet.LightGbmRegressionModelParameters);
        catalog.register('LightGBMBinaryExec', mlnet.LightGbmBinaryModelParameters);
        catalog.register('Linear2CExec', mlnet.LinearBinaryModelParameters);
        catalog.register('LinearModelStats', mlnet.LinearModelParameterStatistics);
        catalog.register('MaFactPredXf', mlnet.MatrixFactorizationPredictionTransformer);
        catalog.register('MFPredictor', mlnet.MatrixFactorizationModelParameters);
        catalog.register('MulticlassLinear', mlnet.LinearMulticlassModelParameters);
        catalog.register('MultiClassLRExec', mlnet.MaximumEntropyModelParameters);
        catalog.register('MultiClassNaiveBayesPred', mlnet.NaiveBayesMulticlassModelParameters);
        catalog.register('MultiClassNetPredictor', mlnet.MultiClassNetPredictor);
        catalog.register('MulticlassPredXfer', mlnet.MulticlassPredictionTransformer);
        catalog.register('NAReplaceTransform', mlnet.MissingValueReplacingTransformer);
        catalog.register('NgramTransform', mlnet.NgramExtractingTransformer);
        catalog.register('NgramHashTransform', mlnet.NgramHashingTransformer);
        catalog.register('NltTokenizeTransform', mlnet.NltTokenizeTransform);
        catalog.register('Normalizer', mlnet.NormalizingTransformer);
        catalog.register('NormalizeTransform', mlnet.NormalizeTransform);
        catalog.register('OnnxTransform', mlnet.OnnxTransformer);
        catalog.register('OptColTransform', mlnet.OptionalColumnTransform);
        catalog.register('OVAExec', mlnet.OneVersusAllModelParameters);
        catalog.register('pcaAnomExec', mlnet.PcaModelParameters);
        catalog.register('PcaTransform', mlnet.PrincipalComponentAnalysisTransformer);
        catalog.register('PipeDataLoader', mlnet.CompositeDataLoader);
        catalog.register('PlattCaliExec', mlnet.PlattCalibrator);
        catalog.register('PMixCaliPredExec', mlnet.ParameterMixingCalibratedModelParameters);
        catalog.register('PoissonRegressionExec', mlnet.PoissonRegressionModelParameters);
        catalog.register('ProtonNNMCPred', mlnet.ProtonNNMCPred);
        catalog.register('RegressionPredXfer', mlnet.RegressionPredictionTransformer);
        catalog.register('RowToRowMapper', mlnet.RowToRowMapperTransform);
        catalog.register('SsaForecasting', mlnet.SsaForecastingTransformer);
        catalog.register('SSAModel', mlnet.AdaptiveSingularSpectrumSequenceModelerInternal);
        catalog.register('SelectColumnsTransform', mlnet.ColumnSelectingTransformer);
        catalog.register('StopWordsTransform', mlnet.StopWordsTransform);
        catalog.register('TensorFlowTransform', mlnet.TensorFlowTransformer);
        catalog.register('TermLookupTransform', mlnet.ValueMappingTransformer);
        catalog.register('TermTransform', mlnet.ValueToKeyMappingTransformer);
        catalog.register('TermManager', mlnet.TermManager);
        catalog.register('Text', mlnet.TextFeaturizingEstimator);
        catalog.register('TextLoader', mlnet.TextLoader);
        catalog.register('TextNormalizerTransform', mlnet.TextNormalizingTransformer);
        catalog.register('TokenizeTextTransform', mlnet.WordTokenizingTransformer);
        catalog.register('TransformerChain', mlnet.TransformerChain);
        catalog.register('ValueMappingTransformer', mlnet.ValueMappingTransformer);
        catalog.register('XGBoostMulticlass', mlnet.XGBoostMulticlass);
        this._resolve = [];
        const root = new mlnet.ModelHeader(catalog, entries, '', null, this._resolve);
        const version = root.openText('TrainingInfo/Version.txt');
        if (version) {
            [this.version] = version.split(/[\s+\r]+/);
        }
        const schemaReader = root.openBinary('Schema');
        if (schemaReader) {
            this.schema = new mlnet.BinaryLoader(null, schemaReader).schema;
        }
        const transformerChain = root.open('TransformerChain');
        if (transformerChain) {
            this.transformerChain = transformerChain;
        }
        const dataLoaderModel = root.open('DataLoaderModel');
        if (dataLoaderModel) {
            this.dataLoaderModel = dataLoaderModel;
        }
        const predictor = root.open('Predictor');
        if (predictor) {
            this.predictor = predictor;
        }
    }

    async resolve(context) {
        const resolve = async (entry) => {
            let module = null;
            let content = '';
            if (entry.format === 'tf') {
                const protobuf = await import('./protobuf.js');
                module = await context.require('./tf');
                content = new mlnet.Context(context, 'model.pb', entry.bytes, protobuf);
            } else if (entry.format === 'onnx') {
                const protobuf = await import('./protobuf.js');
                module = await context.require('./onnx');
                content = new mlnet.Context(context, 'model.onnx', entry.bytes, protobuf);
            } else {
                throw new mlnet.Error(`Unsupported ML.NET model format '${entry.format}'.`);
            }
            const factory = new module.ModelFactory();
            await factory.match(content);
            const model = await factory.open(content);
            if (model && Array.isArray(model.modules) && model.modules.length > 0) {
                return model.modules[0];
            }
            return null;
        };
        const results = await Promise.all(this._resolve.map((entry) => resolve(entry).catch(() => null)));
        for (let i = 0; i < this._resolve.length; i++) {
            if (results[i]) {
                this._resolve[i].target.Model = results[i];
            }
        }
    }
};

mlnet.Context = class {

    constructor(context, identifier, bytes, protobuf) {
        this._context = context;
        this._protobuf = protobuf;
        this._identifier = identifier;
        this._stream = new base.BinaryStream(bytes);
        this._tags = new Map();
    }

    get identifier() {
        return this._identifier;
    }

    get stream() {
        return this._stream;
    }

    set(type, value) {
        this.type = type;
        this.value = value;
        return type;
    }

    async require(id) {
        return this._context.require(id);
    }

    async metadata(id) {
        return this._context.metadata(id);
    }

    async request(file, encoding) {
        return this._context.request(file, encoding);
    }

    async read(type) {
        if (type === 'protobuf.binary') {
            return this._protobuf.BinaryReader.open(this.stream);
        }
        throw new mlnet.Error(`Unsupported read type '${type}'.`);
    }

    async tags(type) {
        if (!this._tags.has(type)) {
            let tags = new Map();
            try {
                const reader = this._protobuf.BinaryReader.open(this.stream);
                tags = type === 'pb+' ? reader.decode() : reader.signature();
            } catch {
                // continue regardless of error
            }
            this.stream.seek(0);
            this._tags.set(type, tags);
        }
        return this._tags.get(type);
    }

    async peek() {
        return undefined;
    }

    error(err) {
        this._context.error(err, false);
    }
};

mlnet.ComponentCatalog = class {

    constructor() {
        this._registry = new Map();
    }

    register(signature, type) {
        this._registry.set(signature, type);
    }

    create(signature, context) {
        if (!this._registry.has(signature)) {
            throw new mlnet.Error(`Unsupported loader signature '${signature}'.`);
        }
        const type = this._registry.get(signature);
        return Reflect.construct(type, [context]);
    }
};

mlnet.ModelHeader = class {

    constructor(catalog, entries, directory, data, resolve) {
        this._entries = entries;
        this._catalog = catalog;
        this._directory = directory;
        this._resolve = resolve;
        if (data) {
            const reader = new mlnet.BinaryReader(data);
            const decoder = new TextDecoder('ascii');
            reader.assert('ML\0MODEL');
            this.versionWritten = reader.uint32();
            this.versionReadable = reader.uint32();
            const modelBlockOffset = reader.uint64().toNumber();
            /* let modelBlockSize = */ reader.uint64();
            const stringTableOffset = reader.uint64().toNumber();
            const stringTableSize = reader.uint64().toNumber();
            const stringCharsOffset = reader.uint64().toNumber();
            /* v stringCharsSize = */ reader.uint64();
            this.modelSignature = decoder.decode(reader.read(8));
            this.modelVersionWritten = reader.uint32();
            this.modelVersionReadable = reader.uint32();
            this.loaderSignature = decoder.decode(reader.read(24).filter((c) => c !== 0));
            this.loaderSignatureAlt = decoder.decode(reader.read(24).filter((c) => c !== 0));
            const tailOffset = reader.uint64().toNumber();
            /* let tailLimit = */ reader.uint64();
            const assemblyNameOffset = reader.uint64().toNumber();
            const assemblyNameSize = reader.uint32();
            if (stringTableOffset !== 0 && stringCharsOffset !== 0) {
                reader.seek(stringTableOffset);
                const stringCount = stringTableSize >> 3;
                const stringSizes = [];
                let previousStringSize = 0;
                for (let i = 0; i < stringCount; i++) {
                    const stringSize = reader.uint64().toNumber();
                    stringSizes.push(stringSize - previousStringSize);
                    previousStringSize = stringSize;
                }
                reader.seek(stringCharsOffset);
                this.strings = [];
                for (let i = 0; i < stringCount; i++) {
                    const cch = stringSizes[i] >> 1;
                    let sb = '';
                    for (let ich = 0; ich < cch; ich++) {
                        sb += String.fromCharCode(reader.uint16());
                    }
                    this.strings.push(sb);
                }
            }
            if (assemblyNameOffset !== 0) {
                reader.seek(assemblyNameOffset);
                this.assemblyName = decoder.decode(reader.read(assemblyNameSize));
            }
            reader.seek(tailOffset);
            reader.assert('LEDOM\0LM');
            this._reader = reader;
            this._reader.seek(modelBlockOffset);
        }
    }

    get reader() {
        return this._reader;
    }

    string(empty) {
        const id = this.reader.int32();
        if (empty === null && id < 0) {
            return null;
        }
        return this.strings[id];
    }

    open(name) {
        const dir = this._directory.length > 0 ? `${this._directory}/` : this._directory;
        name = dir + name;
        const key = `${name}/Model.key`;
        const stream = this._entries.get(key) || this._entries.get(key.replace(/\//g, '\\'));
        if (stream) {
            const buffer = stream.peek();
            const context = new mlnet.ModelHeader(this._catalog, this._entries, name, buffer, this._resolve);
            const value = this._catalog.create(context.loaderSignature, context);
            value.__type__ = value.__type__ || context.loaderSignature;
            value.__name__ = name;
            return value;
        }
        return null;
    }

    openBinary(name) {
        const dir = this._directory.length > 0 ? `${this._directory}/` : this._directory;
        name = dir + name;
        const stream = this._entries.get(name) || this._entries.get(name.replace(/\//g, '\\'));
        if (stream) {
            return new mlnet.BinaryReader(stream);
        }
        return null;
    }

    openText(name) {
        const dir = this._directory.length > 0 ? `${this._directory}/` : this._directory;
        name = dir + name;
        const stream = this._entries.get(name) || this._entries.get(name.replace(/\//g, '\\'));
        if (stream) {
            const buffer = stream.peek();
            const decoder = new TextDecoder('utf-8');
            return decoder.decode(buffer);
        }
        return null;
    }

    check(signature, verWrittenCur, verWeCanReadBack) {
        return signature === this.modelSignature && verWrittenCur >= this.modelVersionReadable && verWeCanReadBack <= this.modelVersionWritten;
    }

    resolve(target, format, bytes) {
        this._resolve.push({ target, format, bytes });
    }
};

mlnet.BinaryReader = class {

    constructor(data) {
        this._reader = base.BinaryReader.open(data);
    }

    seek(position) {
        this._reader.seek(position);
    }

    skip(offset) {
        this._reader.skip(offset);
    }

    read(length) {
        return this._reader.read(length);
    }

    boolean() {
        return this._reader.boolean();
    }

    booleans(count) {
        const values = [];
        for (let i = 0; i < count; i++) {
            values.push(this.boolean());
        }
        return values;
    }

    byte() {
        return this._reader.byte();
    }

    int16() {
        return this._reader.int16();
    }

    int32() {
        return this._reader.int32();
    }

    int32s(count) {
        const values = [];
        for (let i = 0; i < count; i++) {
            values.push(this.int32());
        }
        return values;
    }

    int64() {
        return this._reader.int64();
    }

    uint16() {
        return this._reader.uint16();
    }

    uint32() {
        return this._reader.uint32();
    }

    uint32s(count) {
        const values = [];
        for (let i = 0; i < count; i++) {
            values.push(this.uint32());
        }
        return values;
    }

    uint64() {
        return this._reader.uint64();
    }

    float32() {
        return this._reader.float32();
    }

    float32s(count) {
        const values = [];
        for (let i = 0; i < count; i++) {
            values.push(this.float32());
        }
        return values;
    }

    float64() {
        return this._reader.float64();
    }

    float64s(count) {
        const values = [];
        for (let i = 0; i < count; i++) {
            values.push(this.float64());
        }
        return values;
    }

    string() {
        const size = this.leb128();
        const buffer = this.read(size);
        return new TextDecoder('utf-8').decode(buffer);
    }

    leb128() {
        let result = 0;
        let shift = 0;
        let value = 0;
        do {
            value = this.byte();
            result |= (value & 0x7F) << shift;
            shift += 7;
        } while ((value & 0x80) !== 0);
        return result;
    }

    match(text) {
        const position = this.position;
        for (let i = 0; i < text.length; i++) {
            if (this.byte() !== text.charCodeAt(i)) {
                this.seek(position);
                return false;
            }
        }
        return true;
    }

    assert(text) {
        if (!this.match(text)) {
            throw new mlnet.Error(`Invalid '${text.split('\0').join('')}' signature.`);
        }
    }
};

mlnet.BinaryLoader = class { // 'BINLOADR'

    constructor(context, reader) {
        if (context) {
            if (context.modelVersionWritten >= 0x00010002) {
                this.Threads = context.reader.int32();
                this.GeneratedRowIndexName = context.string(null);
            }
            this.ShuffleBlocks = context.modelVersionWritten >= 0x00010003 ? context.reader.float64() : 4;
            reader = context.openBinary('Schema.idv');
        }
        // https://github.com/dotnet/machinelearning/blob/master/docs/code/IdvFileFormat.md
        reader.assert('CML\0DVB\0');
        reader.skip(8); // version
        reader.skip(8); // compatibleVersion
        const tableOfContentsOffset = reader.uint64().toNumber();
        const tailOffset = reader.int64().toNumber();
        reader.int64(); // rowCount
        const columnCount = reader.int32();
        reader.seek(tailOffset);
        reader.assert('\0BVD\0LMC');
        reader.seek(tableOfContentsOffset);
        this.schema = {};
        this.schema.inputs = [];
        const columns = new Map();
        for (let c = 0; c < columnCount; c  ++) {
            const input = {};
            input.name = reader.string();
            input.type = new mlnet.Codec(reader);
            input.compression = reader.byte(); // None = 0, Deflate = 1
            input.rowsPerBlock = reader.leb128();
            input.lookupOffset = reader.int64();
            input.metadataTocOffset = reader.int64();
            columns.set(input.name, input);
        }
        for (const input of columns.values()) {
            this.schema.inputs.push(input);
        }
    }
};

mlnet.TransformerChain = class {

    constructor(context) {
        const reader = context.reader;
        const length = reader.int32();
        this.scopes = [];
        this.chain = [];
        for (let i = 0; i < length; i++) {
            this.scopes.push(reader.int32()); // 0x01 = Training, 0x02 = Testing, 0x04 = Scoring
            const dirName = `Transform_${(`00${i}`).slice(-3)}`;
            const transformer = context.open(dirName);
            this.chain.push(transformer);
        }
    }
};

mlnet.TransformBase = class {
};

mlnet.RowToRowTransformBase = class extends mlnet.TransformBase {
};

mlnet.RowToRowTransformerBase = class {
};

mlnet.RowToRowMapperTransformBase = class extends mlnet.RowToRowTransformBase {
};

mlnet.OneToOneTransformerBase = class {

    constructor(context) {
        const reader = context.reader;
        const n = reader.int32();
        this.inputs = [];
        this.outputs = [];
        for (let i = 0; i < n; i++) {
            const output = context.string();
            const input = context.string();
            this.outputs.push({ name: output });
            this.inputs.push({ name: input });
        }
    }
};

mlnet.ColumnCopyingTransformer = class {

    constructor(context) {
        const reader = context.reader;
        const length = reader.uint32();
        this.inputs = [];
        this.outputs = [];
        for (let i = 0; i < length; i++) {
            this.outputs.push({ name: context.string() });
            this.inputs.push({ name: context.string() });
        }
    }
};

mlnet.ColumnConcatenatingTransformer = class {

    constructor(context) {
        const reader = context.reader;
        if (context.modelVersionReadable >= 0x00010003) {
            const count = reader.int32();
            for (let i = 0; i < count; i++) {
                this.outputs = [];
                this.outputs.push({ name: context.string() });
                const n = reader.int32();
                this.inputs = [];
                for (let j = 0; j < n; j++) {
                    const input = {
                        name: context.string()
                    };
                    const alias = context.string(null);
                    if (alias) {
                        input.alias = alias;
                    }
                    this.inputs.push(input);
                }
            }
        } else {
            this.precision = reader.int32();
            const n = reader.int32();
            const names = [];
            const inputs = [];
            for (let i = 0; i < n; i++) {
                names.push(context.string());
                const numSources = reader.int32();
                const input = [];
                for (let j = 0; j < numSources; j++) {
                    input.push(context.string());
                }
                inputs.push(input);
            }
            const aliases = [];
            if (context.modelVersionReadable >= 0x00010002) {
                for (let i = 0; i < n; i++) {
                    /* let length = inputs[i].length; */
                    const alias = {};
                    aliases.push(alias);
                    if (context.modelVersionReadable >= 0x00010002) {
                        for (;;) {
                            const j = reader.int32();
                            if (j === -1) {
                                break;
                            }
                            alias[j] = context.string();
                        }
                    }
                }
            }

            if (n > 1) {
                throw new mlnet.Error(`Unsupported ColumnConcatenatingTransformer name count '${n}'.`);
            }

            this.outputs = [];
            for (let i = 0; i < n; i++) {
                this.outputs.push({
                    name: names[i]
                });
                this.inputs = inputs[i];
            }
        }
    }
};

mlnet.PredictionTransformerBase = class {

    constructor(context) {
        this.Model = context.open('Model');
        const trainSchemaReader = context.openBinary('TrainSchema');
        if (trainSchemaReader) {
            this.schema = new mlnet.BinaryLoader(null, trainSchemaReader).schema;
        }
    }
};

mlnet.MatrixFactorizationModelParameters = class {

    constructor(context) {
        const reader = context.reader;
        this.NumberOfRows = reader.int32();
        if (context.modelVersionWritten < 0x00010002) {
            reader.uint64(); // mMin
        }
        this.NumberOfColumns = reader.int32();
        if (context.modelVersionWritten < 0x00010002) {
            reader.uint64(); // nMin
        }
        this.ApproximationRank = reader.int32();

        this._leftFactorMatrix = reader.float32s(this.NumberOfRows * this.ApproximationRank);
        this._rightFactorMatrix = reader.float32s(this.NumberOfColumns * this.ApproximationRank);
    }
};

mlnet.MatrixFactorizationPredictionTransformer = class extends mlnet.PredictionTransformerBase {

    constructor(context) {
        super(context);
        this.MatrixColumnIndexColumnName = context.string();
        this.MatrixRowIndexColumnName = context.string();
    }
};

mlnet.FieldAwareFactorizationMachinePredictionTransformer = class extends mlnet.PredictionTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.inputs = [];
        for (let i = 0; i < this.FieldCount; i++) {
            this.inputs.push({ name: context.string() });
        }
        this.Threshold = reader.float32();
        this.ThresholdColumn = context.string();
        this.outputs = [];
        this.outputs.push({ name: 'Score' });
        this.outputs.push({ name: 'Probability' });
        this.outputs.push({ name: 'PredictedLabel' });
    }
};

mlnet.SingleFeaturePredictionTransformerBase = class extends mlnet.PredictionTransformerBase {

    constructor(context) {
        super(context);
        const featureColumn = context.string(null);
        this.inputs = [];
        this.inputs.push({ name: featureColumn });
        this.outputs = [];
    }
};

mlnet.ClusteringPredictionTransformer = class extends mlnet.SingleFeaturePredictionTransformerBase {

    constructor(context) {
        super(context);
        this.outputs.push({ name: 'Score' });
        this.outputs.push({ name: 'PredictedLabel' });
    }
};

mlnet.AnomalyPredictionTransformer = class extends mlnet.SingleFeaturePredictionTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Threshold = reader.float32();
        this.ThresholdColumn = context.string();
        this.outputs.push({ name: 'Score' });
        this.outputs.push({ name: 'PredictedLabel' });
    }
};

mlnet.AffineNormSerializationUtils = class {

    constructor(context) {
        const reader = context.reader;
        /* cbFloat = */ reader.int32();
        this.NumFeatures = reader.int32();
        const morphCount = reader.int32();
        if (morphCount === -1) {
            this.ScalesSparse = reader.float32s(reader.int32());
            this.OffsetsSparse = reader.float32s(reader.int32());
        } else {
            // debugger;
        }
    }
};

mlnet.RegressionPredictionTransformer = class extends mlnet.SingleFeaturePredictionTransformerBase {

    constructor(context) {
        super(context);
        this.outputs.push({ name: 'Score' });
    }
};

mlnet.BinaryPredictionTransformer = class extends mlnet.SingleFeaturePredictionTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Threshold = reader.float32();
        this.ThresholdColumn = context.string();
        this.outputs.push({ name: 'Score' });
        this.outputs.push({ name: 'PredictedLabel' });
    }
};

mlnet.MulticlassPredictionTransformer = class extends mlnet.SingleFeaturePredictionTransformerBase {

    constructor(context) {
        super(context);
        this.TrainLabelColumn = context.string(null);
        this.inputs.push({ name: this.TrainLabelColumn });
        if (context.modelVersionWritten >= 0x00010002) {
            const scoreColumn = context.string(null);
            const predictedLabelColumn = context.string(null);
            this.outputs.push({ name: scoreColumn || 'Score' });
            this.outputs.push({ name: predictedLabelColumn || 'PredictedLabel' });
        } else {
            this.outputs.push({ name: 'Score' });
            this.outputs.push({ name: 'PredictedLabel' });
        }
    }
};

mlnet.MissingValueReplacingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        for (let i = 0; i < this.inputs.length; i++) {
            const codec = new mlnet.Codec(reader);
            const count = reader.int32();
            this.values = codec.read(reader, count);
        }
    }
};

mlnet.PredictorBase = class {

    constructor(context) {
        const reader = context.reader;
        if (reader.int32() !== 4) {
            throw new mlnet.Error('Invalid float type size.');
        }
    }
};

mlnet.ModelParametersBase = class {

    constructor(context) {
        const reader = context.reader;
        const cbFloat = reader.int32();
        if (cbFloat !== 4) {
            throw new mlnet.Error('This file was saved by an incompatible version.');
        }
    }
};

mlnet.ImageClassificationModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.classCount = reader.int32();
        this.imagePreprocessorTensorInput = reader.string();
        this.imagePreprocessorTensorOutput = reader.string();
        this.graphInputTensor = reader.string();
        this.graphOutputTensor = reader.string();
        const modelReader = context.openBinary('TFModel');
        if (modelReader) {
            const size = modelReader.uint32();
            context.resolve(this, 'tf', modelReader.read(size));
        }
    }
};

mlnet.NaiveBayesMulticlassModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this._labelHistogram = reader.int32s(reader.int32());
        this._featureCount = reader.int32();
        this._featureHistogram = [];
        for (let i = 0; i < this._labelHistogram.length; i++) {
            if (this._labelHistogram[i] > 0) {
                this._featureHistogram.push(reader.int32s(this._featureCount));
            }
        }
        this._absentFeaturesLogProb = reader.float64s(this._labelHistogram.length);
    }
};

mlnet.LinearModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Bias = reader.float32();
        /* let len = */ reader.int32();
        this.Indices = reader.int32s(reader.int32());
        this.Weights = reader.float32s(reader.int32());
    }
};

mlnet.LinearBinaryModelParameters = class extends mlnet.LinearModelParameters {

    constructor(context) {
        super(context);
        if (context.modelVersionWritten > 0x00020001) {
            this.Statistics = context.open('ModelStats');
        }
    }
};

mlnet.ModelStatisticsBase = class {

    constructor(context) {
        const reader = context.reader;
        this.ParametersCount = reader.int32();
        this.TrainingExampleCount = reader.int64().toNumber();
        this.Deviance = reader.float32();
        this.NullDeviance = reader.float32();

    }
};

mlnet.LinearModelParameterStatistics = class extends mlnet.ModelStatisticsBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (context.modelVersionWritten < 0x00010002) {
            if (!reader.boolean()) {
                return;
            }
        }
        const stdErrorValues = reader.float32s(this.ParametersCount);
        const length = reader.int32();
        if (length === this.ParametersCount) {
            this._coeffStdError = stdErrorValues;
        } else {
            this.stdErrorIndices = reader.int32s(this.ParametersCount);
            this._coeffStdError = stdErrorValues;
        }
        this._bias = reader.float32();
        const isWeightsDense = reader.byte();
        const weightsLength = reader.int32();
        const weightsValues = reader.float32s(weightsLength);

        if (isWeightsDense) {
            this._weights = weightsValues;
        } else {
            this.weightsIndices = reader.int32s(weightsLength);
        }
    }
};

mlnet.LinearMulticlassModelParametersBase = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        const numberOfFeatures = reader.int32();
        const numberOfClasses = reader.int32();
        this.Biases = reader.float32s(numberOfClasses);
        const numStarts = reader.int32();
        if (numStarts === 0) {
            /* let numIndices = */ reader.int32();
            /* let numWeights = */ reader.int32();
            this.Weights = [];
            for (let i = 0; i < numberOfClasses; i++) {
                const w = reader.float32s(numberOfFeatures);
                this.Weights.push(w);
            }
        } else {

            const starts = reader.int32s(reader.int32());
            /* let numIndices = */ reader.int32();
            const indices = [];
            for (let i = 0; i < numberOfClasses; i++) {
                indices.push(reader.int32s(starts[i + 1] - starts[i]));
            }
            /* let numValues = */ reader.int32();
            this.Weights = [];
            for (let i = 0; i < numberOfClasses; i++) {
                const values = reader.float32s(starts[i + 1] - starts[i]);
                this.Weights.push(values);
            }
        }

        const labelNamesReader = context.openBinary('LabelNames');
        if (labelNamesReader) {
            this.LabelNames = [];
            for (let i = 0; i < numberOfClasses; i++) {
                const id = labelNamesReader.int32();
                this.LabelNames.push(context.strings[id]);
            }
        }

        const statistics = context.open('ModelStats');
        if (statistics) {
            this.Statistics = statistics;
        }
    }
};

mlnet.LinearMulticlassModelParameters = class extends mlnet.LinearMulticlassModelParametersBase {
};

mlnet.RegressionModelParameters = class extends mlnet.LinearModelParameters {
};

mlnet.PoissonRegressionModelParameters = class extends mlnet.RegressionModelParameters {
};

mlnet.LinearRegressionModelParameters = class extends mlnet.RegressionModelParameters {
};

mlnet.MaximumEntropyModelParameters = class extends mlnet.LinearMulticlassModelParametersBase {
};

mlnet.TokenizingByCharactersTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.UseMarkerChars = reader.boolean();
        this.IsSeparatorStartEnd = context.modelVersionReadable < 0x00010002 ? true : reader.boolean();
    }
};

mlnet.SequencePool = class {

    constructor(reader) {
        this.idLim = reader.int32();
        this.start = reader.int32s(this.idLim + 1);
        this.bytes = reader.read(this.start[this.idLim]);
    }
};

mlnet.NgramExtractingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (this.inputs.length === 1) {
            this._option(context, reader, this);
        } else {
            // debugger;
        }
    }

    _option(context, reader, option) {
        const readWeighting = context.modelVersionReadable >= 0x00010002;
        option.NgramLength = reader.int32();
        option.SkipLength = reader.int32();
        if (readWeighting) {
            option.Weighting = reader.int32();
        }
        option.NonEmptyLevels = reader.booleans(option.NgramLength);
        option.NgramMap = new mlnet.SequencePool(reader);
        if (readWeighting) {
            option.InvDocFreqs = reader.float64s(reader.int32());
        }
    }
};

// mlnet.NgramExtractingTransformer.WeightingCriteria

mlnet.NgramHashingTransformer = class extends mlnet.RowToRowTransformerBase {

    constructor(context) {
        super(context);
        const loadLegacy = context.modelVersionWritten < 0x00010003;
        const reader = context.reader;
        if (loadLegacy) {
            reader.int32(); // cbFloat
        }
        this.inputs = [];
        this.outputs = [];
        const columnsLength = reader.int32();
        if (loadLegacy) {
            // for (let i = 0; i < columnsLength; i++) {
            //     this.Columns.push(new NgramHashingEstimator.ColumnOptions(context));
            // }
        } else {
            for (let i = 0; i < columnsLength; i++) {
                this.outputs.push(context.string());
                const csrc = reader.int32();
                for (let j = 0; j < csrc; j++) {
                    const src = context.string();
                    this.inputs.push(src);
                    // inputs[i][j] = src;
                }
            }
        }
    }
};

mlnet.WordTokenizingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (this.inputs.length === 1) {
            this.Separators = [];
            const count = reader.int32();
            for (let i = 0; i < count; i++) {
                this.Separators.push(String.fromCharCode(reader.int16()));
            }
        } else {
            // debugger;
        }
    }
};

mlnet.TextNormalizingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.CaseMode = reader.byte();
        this.KeepDiacritics = reader.boolean();
        this.KeepPunctuations = reader.boolean();
        this.KeepNumbers = reader.boolean();
    }
};

mlnet.TextNormalizingTransformer.CaseMode = {
    Lower: 0,
    Upper: 1,
    None: 2
};

mlnet.PrincipalComponentAnalysisTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (context.modelVersionReadable === 0x00010001) {
            if (reader.int32() !== 4) {
                throw new mlnet.Error('This file was saved by an incompatible version.');
            }
        }
        this.TransformInfos = [];
        for (let i = 0; i < this.inputs.length; i++) {
            const option = {};
            option.Dimension = reader.int32();
            option.Rank = reader.int32();
            option.Eigenvectors = [];
            for (let j = 0; j < option.Rank; j++) {
                option.Eigenvectors.push(reader.float32s(option.Dimension));
            }
            option.MeanProjected = reader.float32s(reader.int32());
            this.TransformInfos.push(option);
        }
    }
};

mlnet.LpNormNormalizingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;

        if (context.modelVersionWritten <= 0x00010002) {
            /* cbFloat */ reader.int32();
        }
        // let normKindSerialized = context.modelVersionWritten >= 0x00010002;
        if (this.inputs.length === 1) {
            this.EnsureZeroMean = reader.boolean();
            this.Norm = reader.byte();
            this.Scale = reader.float32();
        } else {
            // debugger;
        }
    }
};

mlnet.KeyToVectorMappingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (context.modelVersionWritten === 0x00010001) {
            /* cbFloat = */ reader.int32();
        }
        const columnsLength = this.inputs.length;
        this.Bags = reader.booleans(columnsLength);
    }
};

mlnet.TypeConvertingTransformer = class extends mlnet.OneToOneTransformerBase {
};

mlnet.ImageLoadingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        this.ImageFolder = context.string(null);
    }
};

mlnet.ImageResizingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (this.inputs.length === 1) {
            this._option(reader, this);
        } else {
            this.Options = [];
            for (let i = 0; i < this.inputs.length; i++) {
                const option = {};
                this._option(reader, option);
                this.Options.push(option);
            }
        }
    }

    _option(reader, option) {
        option.Width = reader.int32();
        option.Height = reader.int32();
        option.Resizing = reader.byte();
        option.Anchor = reader.byte();
    }
};

mlnet.ImageResizingTransformer.ResizingKind = {
    IsoPad: 0,
    IsoCrop: 1,
    Fill: 2
};

mlnet.ImageResizingTransformer.Anchor = {
    Right: 0,
    Left: 1,
    Top: 2,
    Bottom: 3,
    Center: 4
};

mlnet.ImagePixelExtractingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (this.inputs.length === 1) {
            this._option(context, reader, this);
        } else {
            this.Options = [];
            for (let i = 0; i < this.inputs.length; i++) {
                const option = {};
                this._option(context, reader, option);
                this.Options.push(option);
            }
        }
    }

    _option(context, reader, option) {
        option.ColorsToExtract = reader.byte();
        option.OrderOfExtraction = context.modelVersionWritten <= 0x00010002 ? mlnet.ImagePixelExtractingTransformer.ColorsOrder.ARGB : reader.byte();
        let planes = option.ColorsToExtract;
        planes = (planes & 0x05) + ((planes >> 1) & 0x05);
        planes = (planes & 0x03) + ((planes >> 2) & 0x03);
        option.Planes = planes & 0xFF;
        option.OutputAsFloatArray = reader.boolean();
        option.OffsetImage = reader.float32();
        option.ScaleImage = reader.float32();
        option.InterleavePixelColors = reader.boolean();
    }
};

mlnet.ImagePixelExtractingTransformer.ColorBits = {
    Alpha: 0x01,
    Red: 0x02,
    Green: 0x04,
    Blue: 0x08,
    Rgb: 0x0E,
    All: 0x0F
};

mlnet.ImagePixelExtractingTransformer.ColorsOrder = {
    ARGB: 1,
    ARBG: 2,
    ABRG: 3,
    ABGR: 4,
    AGRB: 5,
    AGBR: 6
};

mlnet.NormalizingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Options = [];
        for (let i = 0; i < this.inputs.length; i++) {
            let isVector = false;
            let shape = 0;
            let itemKind = '';
            if (context.modelVersionWritten < 0x00010002) {
                isVector = reader.boolean();
                shape = [reader.int32()];
                itemKind = reader.byte();
            } else {
                isVector = reader.boolean();
                itemKind = reader.byte();
                shape = reader.int32s(reader.int32());
            }
            let itemType = '';
            switch (itemKind) {
                case 9: itemType = 'float32'; break;
                case 10: itemType = 'float64'; break;
                default: throw new mlnet.Error(`Unsupported NormalizingTransformer item kind '${itemKind}'.`);
            }
            const type = itemType + (isVector ? `[${shape.map((dim) => dim.toString()).join(',')}]` : '');
            const name = `Normalizer_${(`00${i}`).slice(-3)}`;
            const func = context.open(name);
            this.Options.push({ type, func });
        }
    }
};

mlnet.KeyToValueMappingTransformer = class extends mlnet.OneToOneTransformerBase {
};

mlnet.ValueToKeyMappingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        if (context.modelVersionWritten >= 0x00010003) {
            this.textMetadata = reader.booleans(this.outputs.length + this.inputs.length);
        } else {
            this.textMetadata = [];
            for (let i = 0; i < this.columnPairs.length; i++) {
                this.textMetadata.push(false);
            }
        }
        const vocabulary = context.open('Vocabulary');
        if (vocabulary) {
            this.termMap = vocabulary.termMap;
        }
    }
};

mlnet.TermMap = class {

    constructor(context) {
        const reader = context.reader;
        const mtype = reader.byte();
        switch (mtype) {
            case 0: { // Text
                this.values = [];
                const cstr = reader.int32();
                for (let i = 0; i < cstr; i++) {
                    this.values.push(context.string());
                }
                break;
            }
            case 1: { // Codec
                const codec = new mlnet.Codec(reader);
                const count = reader.int32();
                this.values = codec.read(reader, count);
                break;
            }
            default:
                throw new mlnet.Error(`Unsupported term map type '${mtype}'.`);
        }
    }
};

mlnet.TermManager = class {

    constructor(context) {
        const reader = context.reader;
        const cmap = reader.int32();
        this.termMap = [];
        if (context.modelVersionWritten >= 0x00010002) {
            for (let i = 0; i < cmap; ++i) {
                this.termMap.push(new mlnet.TermMap(context));
                // debugger;
                // termMap[i] = TermMap.Load(c, host, CodecFactory);
            }
        } else {
            throw new mlnet.Error('Unsupported TermManager version.');
            // for (let i = 0; i < cmap; ++i) {
            //    debugger;
            //    // termMap[i] = TermMap.TextImpl.Create(c, host)
            // }
        }
    }
};

mlnet.ValueMappingTransformer = class extends mlnet.OneToOneTransformerBase {

    constructor(context) {
        super(context);
        this.keyColumnName = 'Key';
        if (context.check('TXTLOOKT', 0x00010002, 0x00010002)) {
            this.keyColumnName = 'Term';
        }
    }
};

mlnet.KeyToVectorTransform = class {
};

mlnet.GenericScoreTransform = class {
};

mlnet.CompositeDataLoader = class {

    constructor(context) {
        /* let loader = */ context.open('Loader');
        const reader = context.reader;
        // LoadTransforms
        reader.int32(); // floatSize
        const cxf = reader.int32();
        const tagData = [];
        for (let i = 0; i < cxf; i++) {
            let tag = '';
            let args = null;
            if (context.modelVersionReadable >= 0x00010002) {
                tag = context.string();
                args = context.string(null);
            }
            tagData.push([tag, args]);
        }
        this.chain = [];
        for (let j = 0; j < cxf; j++) {
            const name = `Transform_${(`00${j}`).slice(-3)}`;
            const transform = context.open(name);
            this.chain.push(transform);
        }
    }
};

mlnet.RowToRowMapperTransform = class extends mlnet.RowToRowTransformBase {

    constructor(context) {
        super(context);
        const mapper = context.open('Mapper');
        this.__type__ = mapper.__type__;
        for (const key of Object.keys(mapper)) {
            this[key] = mapper[key];
        }
    }
};

mlnet.ImageClassificationTransformer = class extends mlnet.RowToRowTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.addBatchDimensionInput = reader.boolean();
        const numInputs = reader.int32();
        this.inputs = [];
        for (let i = 0; i < numInputs; i++) {
            this.inputs.push({ name: context.string() });
        }
        this.outputs = [];
        const numOutputs = reader.int32();
        for (let i = 0; i < numOutputs; i++) {
            this.outputs.push({ name: context.string() });
        }
        this.labelColumn = reader.string();
        this.checkpointName = reader.string();
        this.arch = reader.int32(); // Architecture
        this.scoreColumnName = reader.string();
        this.predictedColumnName = reader.string();
        this.learningRate = reader.float32();
        this.classCount = reader.int32();
        this.keyValueAnnotations = [];
        for (let i = 0; i < this.classCount; i++) {
            this.keyValueAnnotations.push(context.string());
        }
        this.predictionTensorName = reader.string();
        this.softMaxTensorName = reader.string();
        this.jpegDataTensorName = reader.string();
        this.resizeTensorName = reader.string();
    }
};

mlnet.OnnxTransformer = class extends mlnet.RowToRowTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        const modelReader = context.openBinary('OnnxModel');
        if (modelReader) {
            const size = modelReader.uint32();
            context.resolve(this, 'onnx', modelReader.read(size));
        }
        const numInputs = context.modelVersionWritten > 0x00010001 ? reader.int32() : 1;
        this.inputs = [];
        for (let i = 0; i < numInputs; i++) {
            this.inputs.push({ name: context.string() });
        }
        const numOutputs = context.modelVersionWritten > 0x00010001 ? reader.int32() : 1;
        this.outputs = [];
        for (let i = 0; i < numOutputs; i++) {
            this.outputs.push({ name: context.string() });
        }
        if (context.modelVersionWritten > 0x0001000C) {
            const customShapeInfosLength = reader.int32();
            this.LoadedCustomShapeInfos = [];
            for (let i = 0; i < customShapeInfosLength; i++) {
                this.LoadedCustomShapeInfos.push({
                    name: context.string(),
                    shape: reader.int32s(reader.int32())
                });
            }
        }
    }
};

mlnet.OptionalColumnTransform = class extends mlnet.RowToRowMapperTransformBase {
};

mlnet.TensorFlowTransformer = class extends mlnet.RowToRowTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.IsFrozen = context.modelVersionReadable >= 0x00010002 ? reader.boolean() : true;
        this.AddBatchDimensionInput = context.modelVersionReadable >= 0x00010003 ? reader.boolean() : true;
        const numInputs = reader.int32();
        this.inputs = [];
        for (let i = 0; i < numInputs; i++) {
            this.inputs.push({ name: context.string() });
        }
        const numOutputs = context.modelVersionReadable >= 0x00010002 ? reader.int32() : 1;
        this.outputs = [];
        for (let i = 0; i < numOutputs; i++) {
            this.outputs.push({ name: context.string() });
        }
    }
};

mlnet.OneVersusAllModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.UseDist = reader.boolean();
        const len = reader.int32();
        this.chain = [];
        for (let i = 0; i < len; i++) {
            const name = `SubPredictor_${(`00${i}`).slice(-3)}`;
            const predictor = context.open(name);
            this.chain.push(predictor);
        }
    }
};

mlnet.TextFeaturizingEstimator = class {

    constructor(context) {

        if (context.modelVersionReadable === 0x00010001) {
            const reader = context.reader;
            const n = reader.int32();
            this.chain = [];
            /* let loader = */ context.open('Loader');
            for (let i = 0; i < n; i++) {
                const name = `Step_${(`00${i}`).slice(-3)}`;
                const transformer = context.open(name);
                this.chain.push(transformer);
                // debugger;
            }

            // throw new mlnet.Error('Unsupported TextFeaturizingEstimator format.');
        } else {
            const chain = context.open('Chain');
            this.chain = chain.chain;
        }
    }
};

mlnet.TextLoader = class {

    constructor(context) {
        const reader = context.reader;
        reader.int32(); // floatSize
        this.MaxRows = reader.int64();
        this.Flags = reader.uint32();
        this.InputSize = reader.int32();
        const separatorCount = reader.int32();
        this.Separators = [];
        for (let i = 0; i < separatorCount; i++) {
            this.Separators.push(String.fromCharCode(reader.uint16()));
        }
        this.Bindinds = new mlnet.TextLoader.Bindinds(context);
    }
};

mlnet.TextLoader.Bindinds = class {

    constructor(context) {
        const reader = context.reader;
        const cinfo = reader.int32();
        for (let i = 0; i < cinfo; i++) {
            // debugger;
        }
    }
};

mlnet.CalibratedPredictorBase = class {

    constructor(predictor, calibrator) {
        this.SubPredictor = predictor;
        this.Calibrator = calibrator;
    }
};

mlnet.ValueMapperCalibratedPredictorBase = class extends mlnet.CalibratedPredictorBase {
};

mlnet.CalibratedModelParametersBase = class {

    constructor(context) {
        this.Predictor = context.open('Predictor');
        this.Calibrator = context.open('Calibrator');
    }
};

mlnet.ValueMapperCalibratedModelParametersBase = class extends mlnet.CalibratedModelParametersBase {
};

mlnet.CalibratedPredictor = class extends mlnet.ValueMapperCalibratedPredictorBase {

    constructor(context) {
        const predictor = context.open('Predictor');
        const calibrator = context.open('Calibrator');
        super(predictor, calibrator);
    }
};

mlnet.ParameterMixingCalibratedModelParameters = class extends mlnet.ValueMapperCalibratedModelParametersBase {
};

mlnet.FieldAwareFactorizationMachineModelParameters = class {

    constructor(context) {
        const reader = context.reader;
        this.Norm = reader.boolean();
        this.FieldCount = reader.int32();
        this.FeatureCount = reader.int32();
        this.LatentDim = reader.int32();
        this.LinearWeights = reader.float32s(reader.int32());
        this.LatentWeights = reader.float32s(reader.int32());
    }
};

mlnet.KMeansModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.k = reader.int32();
        this.Dimensionality = reader.int32();
        this.Centroids = [];
        for (let i = 0; i < this.k; i++) {
            const count = context.modelVersionWritten >= 0x00010002 ? reader.int32() : this.Dimensionality;
            const indices = count < this.Dimensionality ? reader.int32s(count) : null;
            const values = reader.float32s(count);
            this.Centroids.push({ indices, values });
        }
        // input type = float32[dimensionality]
        // output type = float32[k]
    }
};

mlnet.PcaModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Dimension = reader.int32();
        this.Rank = reader.int32();
        const center = reader.boolean();
        if (center) {
            this.Mean = reader.float32s(this.Dimension);
        } else {
            this.Mean = [];
        }
        this.EigenVectors = [];
        for (let i = 0; i < this.Rank; ++i) {
            this.EigenVectors.push(reader.float32s(this.Dimension));
        }
        // input type -> float32[Dimension]
    }
};

mlnet.TreeEnsembleModelParameters = class extends mlnet.ModelParametersBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        const usingDefaultValues = context.modelVersionWritten >= this.VerDefaultValueSerialized;
        const categoricalSplits = context.modelVersionWritten >= this.VerCategoricalSplitSerialized;
        this.TrainedEnsemble = new mlnet.InternalTreeEnsemble(context, usingDefaultValues, categoricalSplits);
        this.InnerOptions = context.string(null);
        if (context.modelVersionWritten >= this.VerNumFeaturesSerialized) {
            this.NumFeatures = reader.int32();
        }
        // input type -> float32[NumFeatures]
        // output type -> float32
    }
};

mlnet.InternalTreeEnsemble = class {

    constructor(context, usingDefaultValues, categoricalSplits) {
        const reader = context.reader;
        this.Trees = [];
        const numTrees = reader.int32();
        for (let i = 0; i < numTrees; i++) {
            switch (reader.byte()) {
                case mlnet.InternalTreeEnsemble.TreeType.Regression:
                    this.Trees.push(new mlnet.InternalRegressionTree(context, usingDefaultValues, categoricalSplits));
                    break;
                case mlnet.InternalTreeEnsemble.TreeType.FastForest:
                    this.Trees.push(new mlnet.InternalQuantileRegressionTree(context, usingDefaultValues, categoricalSplits));
                    break;
                case mlnet.InternalTreeEnsemble.TreeType.Affine:
                    // Affine regression trees do not actually work, nor is it clear how they ever
                    // could have worked within TLC, so the chance of this happening seems remote.
                    throw new mlnet.Error('Affine regression trees unsupported.');
                default:
                    throw new mlnet.Error('Unsupported ensemble tree type.');
            }
        }
        this.Bias = reader.float64();
        this.FirstInputInitializationContent = context.string(null);
    }
};

mlnet.InternalRegressionTree = class {

    constructor(context, usingDefaultValue, categoricalSplits) {
        const reader = context.reader;
        this.NumLeaves = reader.int32();
        this.MaxOuptut = reader.float64();
        this.Weight = reader.float64();
        this.LteChild = reader.int32s(reader.int32());
        this.GtChild = reader.int32s(reader.int32());
        this.SplitFeatures = reader.int32s(reader.int32());
        if (categoricalSplits) {
            const categoricalNodeIndices = reader.int32s(reader.int32());
            if (categoricalNodeIndices.length > 0) {
                this.CategoricalSplitFeatures = [];
                this.CategoricalSplitFeatureRanges = [];
                for (const index of categoricalNodeIndices) {
                    this.CategoricalSplitFeatures[index] = reader.int32s(reader.int32());
                    this.CategoricalSplitFeatureRanges[index] = reader.int32s(2);
                }
            }
        }
        this.Thresholds = reader.uint32s(reader.int32());
        this.RawThresholds = reader.float32s(reader.int32());
        this.DefaultValueForMissing = usingDefaultValue ? reader.float32s(reader.int32()) : null;
        this.LeafValues = reader.float64s(reader.int32());

        this.SplitGain = reader.float64s(reader.int32());
        this.GainPValue = reader.float64s(reader.int32());
        this.PreviousLeafValue = reader.float64s(reader.int32());
    }
};

mlnet.InternalTreeEnsemble.TreeType = {
    Regression: 0,
    Affine: 1,
    FastForest: 2
};

mlnet.TreeEnsembleModelParametersBasedOnRegressionTree = class extends mlnet.TreeEnsembleModelParameters {
};

mlnet.FastTreeTweedieModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010001;
    }

    get VerDefaultValueSerialized() {
        return 0x00010002;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010003;
    }
};

mlnet.FastTreeRankingModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010002;
    }

    get VerDefaultValueSerialized() {
        return 0x00010004;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010005;
    }
};

mlnet.FastTreeBinaryModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010002;
    }

    get VerDefaultValueSerialized() {
        return 0x00010004;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010005;
    }
};

mlnet.FastTreeRegressionModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010002;
    }

    get VerDefaultValueSerialized() {
        return 0x00010004;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010005;
    }
};

mlnet.LightGbmRegressionModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010002;
    }

    get VerDefaultValueSerialized() {
        return 0x00010004;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010005;
    }
};

mlnet.LightGbmBinaryModelParameters = class extends mlnet.TreeEnsembleModelParametersBasedOnRegressionTree {

    get VerNumFeaturesSerialized() {
        return 0x00010002;
    }

    get VerDefaultValueSerialized() {
        return 0x00010004;
    }

    get VerCategoricalSplitSerialized() {
        return 0x00010005;
    }
};

mlnet.FeatureWeightsCalibratedModelParameters = class extends mlnet.ValueMapperCalibratedModelParametersBase {
};

mlnet.FastTreePredictionWrapper = class {
};

mlnet.FastForestClassificationPredictor = class extends mlnet.FastTreePredictionWrapper {
};

mlnet.PlattCalibrator = class {

    constructor(context) {
        const reader = context.reader;
        this.ParamA = reader.float64();
        this.ParamB = reader.float64();
    }
};

mlnet.Codec = class {

    constructor(reader) {
        this.name = reader.string();
        const size = reader.leb128();
        const data = reader.read(size);
        reader = new mlnet.BinaryReader(data);
        switch (this.name) {
            case 'Boolean': break;
            case 'Single': break;
            case 'Double': break;
            case 'Byte': break;
            case 'Int32': break;
            case 'UInt32': break;
            case 'Int64': break;
            case 'TextSpan': break;
            case 'VBuffer':
                this.itemType = new mlnet.Codec(reader);
                this.dims = reader.int32s(reader.int32());
                break;
            case 'Key':
            case 'Key2':
                this.itemType = new mlnet.Codec(reader);
                this.count = reader.uint64().toNumber();
                break;
            default:
                throw new mlnet.Error(`Unsupported codec '${this.name}'.`);
        }
    }

    read(reader, count) {
        const values = [];
        switch (this.name) {
            case 'Single':
                for (let i = 0; i < count; i++) {
                    values.push(reader.float32());
                }
                break;
            case 'Int32':
                for (let i = 0; i < count; i++) {
                    values.push(reader.int32());
                }
                break;
            case 'Int64':
                for (let i = 0; i < count; i++) {
                    values.push(reader.int64());
                }
                break;
            default:
                throw new mlnet.Error(`Unsupported codec read operation '${this.name}'.`);
        }
        return values;
    }
};

mlnet.SequentialTransformerBase = class {

    constructor(context) {
        const reader = context.reader;
        this.WindowSize = reader.int32();
        this.InitialWindowSize = reader.int32();
        this.inputs = [];
        this.inputs.push({ name: context.string() });
        this.outputs = [];
        this.outputs.push({ name: context.string() });
        this.ConfidenceLowerBoundColumn = reader.string();
        this.ConfidenceUpperBoundColumn = reader.string();
        this.Type = new mlnet.Codec(reader);
    }
};

mlnet.AnomalyDetectionStateBase = class {

    constructor(context) {
        const reader = context.reader;
        this.LogMartingaleUpdateBuffer = mlnet.AnomalyDetectionStateBase._deserializeFixedSizeQueueDouble(reader);
        this.RawScoreBuffer = mlnet.AnomalyDetectionStateBase._deserializeFixedSizeQueueDouble(reader);
        this.LogMartingaleValue = reader.float64();
        this.SumSquaredDist = reader.float64();
        this.MartingaleAlertCounter = reader.int32();
    }

    static _deserializeFixedSizeQueueDouble(reader) {
        /* let capacity = */ reader.int32();
        const count = reader.int32();
        const queue = [];
        for (let i = 0; i < count; i++) {
            queue.push(reader.float64());
        }
        return queue;
    }
};

mlnet.SequentialAnomalyDetectionTransformBase = class extends mlnet.SequentialTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.Martingale = reader.byte();
        this.ThresholdScore = reader.byte();
        this.Side = reader.byte();
        this.PowerMartingaleEpsilon = reader.float64();
        this.AlertThreshold = reader.float64();
        this.State = new mlnet.AnomalyDetectionStateBase(context);
    }
};

mlnet.TimeSeriesUtils = class {

    static deserializeFixedSizeQueueSingle(reader) {
        /* const capacity = */ reader.int32();
        const count = reader.int32();
        const queue = [];
        for (let i = 0; i < count; i++) {
            queue.push(reader.float32());
        }
        return queue;
    }
};

mlnet.IidAnomalyDetectionBase = class extends mlnet.SequentialAnomalyDetectionTransformBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.WindowedBuffer = mlnet.TimeSeriesUtils.deserializeFixedSizeQueueSingle(reader);
        this.InitialWindowedBuffer = mlnet.TimeSeriesUtils.deserializeFixedSizeQueueSingle(reader);
    }
};

mlnet.IidAnomalyDetectionBaseWrapper = class {

    constructor(context) {
        const internalTransform = new mlnet.IidAnomalyDetectionBase(context);
        for (const key of Object.keys(internalTransform)) {
            this[key] = internalTransform[key];
        }
    }
};

mlnet.IidChangePointDetector = class extends mlnet.IidAnomalyDetectionBaseWrapper {
};

mlnet.IidSpikeDetector = class extends mlnet.IidAnomalyDetectionBaseWrapper {
};

mlnet.SequenceModelerBase = class {
};

mlnet.RankSelectionMethod = {
    Fixed: 0,
    Exact: 1,
    Fact: 2
};

mlnet.AdaptiveSingularSpectrumSequenceModelerInternal = class extends mlnet.SequenceModelerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this._seriesLength = reader.int32();
        this._windowSize = reader.int32();
        this._trainSize = reader.int32();
        this._rank = reader.int32();
        this._discountFactor = reader.float32();
        this._rankSelectionMethod = reader.byte(); // RankSelectionMethod
        const isWeightSet = reader.byte();
        this._alpha = reader.float32s(reader.int32());
        if (context.modelVersionReadable >= 0x00010002) {
            this._state = reader.float32s(reader.int32());
        }
        this.ShouldComputeForecastIntervals = reader.byte();
        this._observationNoiseVariance = reader.float32();
        this._autoregressionNoiseVariance = reader.float32();
        this._observationNoiseMean = reader.float32();
        this._autoregressionNoiseMean = reader.float32();
        if (context.modelVersionReadable >= 0x00010002) {
            this._nextPrediction = reader.float32();
        }
        this._maxRank = reader.int32();
        this._shouldStablize = reader.byte();
        this._shouldMaintainInfo = reader.byte();
        this._maxTrendRatio = reader.float64();
        if (isWeightSet) {
            this._wTrans = reader.float32s(reader.int32());
            this._y = reader.float32s(reader.int32());
        }
        this._buffer = mlnet.TimeSeriesUtils.deserializeFixedSizeQueueSingle(reader);
    }
};

mlnet.SequentialForecastingTransformBase = class extends mlnet.SequentialTransformerBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this._outputLength = reader.int32();
    }
};

mlnet.SsaForecastingBaseWrapper = class extends mlnet.SequentialForecastingTransformBase {

    constructor(context) {
        super(context);
        const reader = context.reader;
        this.IsAdaptive = reader.boolean();
        this.Horizon = reader.int32();
        this.ConfidenceLevel = reader.float32();
        this.WindowedBuffer = mlnet.TimeSeriesUtils.deserializeFixedSizeQueueSingle(reader);
        this.InitialWindowedBuffer = mlnet.TimeSeriesUtils.deserializeFixedSizeQueueSingle(reader);
        this.Model = context.open('SSA');
    }
};

mlnet.SsaForecastingTransformer = class extends mlnet.SsaForecastingBaseWrapper {
};

mlnet.ColumnSelectingTransformer = class {

    constructor(context) {
        const reader = context.reader;
        if (context.check('DRPCOLST', 0x00010002, 0x00010002)) {
            throw new mlnet.Error("'LoadDropColumnsTransform' not supported.");
        } else if (context.check('CHSCOLSF', 0x00010001, 0x00010001)) {
            reader.int32(); // cbFloat
            this.KeepHidden = this._getHiddenOption(reader.byte());
            const count = reader.int32();
            this.inputs = [];
            for (let colIdx = 0; colIdx < count; colIdx++) {
                const dst = context.string();
                this.inputs.push(dst);
                context.string(); // src
                this._getHiddenOption(reader.byte()); // colKeepHidden
            }
        } else {
            const keepColumns = reader.boolean();
            this.KeepHidden = reader.boolean();
            this.IgnoreMissing = reader.boolean();
            const length = reader.int32();
            this.inputs = [];
            for (let i = 0; i < length; i++) {
                this.inputs.push({ name: context.string() });
            }
            if (keepColumns) {
                this.ColumnsToKeep = this.inputs;
            } else {
                this.ColumnsToDrop = this.inputs;
            }
        }
    }

    _getHiddenOption(value) {
        switch (value) {
            case 1: return true;
            case 2: return false;
            default: throw new mlnet.Error('Unsupported hide option specified');
        }
    }
};

mlnet.XGBoostMulticlass = class {};

mlnet.NltTokenizeTransform = class {};

mlnet.DropColumnsTransform = class {};

mlnet.StopWordsTransform = class {};

mlnet.CSharpTransform = class {};

mlnet.GenericScoreTransform = class {};

mlnet.NormalizeTransform = class {};

mlnet.CdfColumnFunction = class {
};

mlnet.MultiClassNetPredictor = class {};

mlnet.ProtonNNMCPred = class {};

mlnet.Utility = class {

    static enum(type, value) {
        if (type) {
            mlnet.Utility._enums = mlnet.Utility._enums || new Map();
            if (!mlnet.Utility._enums.has(type)) {
                let obj = mlnet;
                const id = type.split('.');
                while (obj && id.length > 0) {
                    obj = obj[id.shift()];
                }
                if (obj) {
                    const entries = new Map(Object.entries(obj).map(([key, value]) => [value, key]));
                    mlnet.Utility._enums.set(type, entries);
                } else {
                    mlnet.Utility._enums.set(type, new Map());
                }
            }
            const map = mlnet.Utility._enums.get(type);
            if (map.has(value)) {
                return map.get(value);
            }
        }
        return value;
    }
};

mlnet.Error = class extends Error {

    constructor(message) {
        super(message);
        this.name = 'Error loading ML.NET model.';
    }
};

export const ModelFactory = mlnet.ModelFactory;