crosslang-libs/Tesses.CrossLang.BuildEssentials/src/crossvmfile.tcross

func Tesses.CrossLang.CrossVMFile()
{
    return {
        Info = "",
        Name = "",
        Version = "",
        Dependencies = [],
        Chunks = [],
        Strings = [],
        Functions = [],
        Resources = [],
        Sections = [],
        Ensure = (this,strm,buff,len) =>{
            if(strm.ReadBlock(buff,0,len) != len)
                throw $"Could not read {len} byte(s)";
        },
        EnsureInt = (this,strm)=>{
            var buff = ByteArray(4);
            this.Ensure(strm,buff,4);
            var number = 0;
            number |= buff[0] << 24;
            number |= buff[1] << 16;
            number |= buff[2] << 8;
            number |= buff[3];
            return number;
        },
        EnsureString = (this,strm)=>{
            var len = this.EnsureInt(strm);
            var buff = ByteArray(len);
            this.Ensure(strm, buff,len);
            return buff.ToString();
        },
        GetString = (this,strm)=>{
            var index = this.EnsureInt(strm);
            if(index < this.Strings.Count) return this.Strings[index];
            throw $"{index} is not less than {this.Strings.Count}";
        },
        Read = (this,stream)=>{
            var header = ByteArray(8);
            this.Ensure(stream, header, header.Count);
            
            var hdrStr = header.ToString();
            if(hdrStr != "TCROSSVM") throw "Invalid TCrossVM image.";
            
            this.Ensure(stream, header, 5);
            
            var version = Tesses.CrossLang.Version.FromBytes(header, 0);
            
            if(version > Tesses.CrossLang.Version.Current) throw "Runtime is too old.";
            this.Ensure(stream, header, 5);
            

            this.Version = Tesses.CrossLang.Version.FromBytes(header,0);

            var sec = ByteArray(4);
            var sectionCount = this.EnsureInt(stream);

            
            for(var i = 0; i < sectionCount; i++)
            {

                this.Ensure(stream, sec, sec.Count);
                hdrStr = sec.ToString();
                var tableLength = this.EnsureInt(stream);
                if(hdrStr == "NAME")
                {
                    this.Name = this.GetString(stream);
                }
                else if(hdrStr == "INFO")
                {
                    this.Info = this.GetString(stream);
                }
                else if(hdrStr == "DEPS")
                {
                    var _name = this.GetString(stream);
                    this.Ensure(stream, header, 5);
                    var _version = Tesses.CrossLang.Version.FromBytes(header,0);
                    this.Dependencies.Add({
                        Name = _name,
                        Version = _version
                    });
                }
                else if(hdrStr == "RESO")
                {
                    var resource = ByteArray(tableLength);
                    this.Ensure(stream,resource,resource.Count);
                    this.Resources.Add(resource);
                }
                else if(hdrStr == "CHKS")
                {
                    var chunkCount = this.EnsureInt(stream);
                    for(var j = 0; j < chunkCount; j++)
                    {
                        var _args = [];
                        var _argCount = this.EnsureInt(stream);
                        for(var k = 0; k < _argCount; k++)
                        {
                            _args.Add(this.GetString(stream));
                        }
                        var _code = ByteArray(this.EnsureInt(stream));
                        this.Ensure(stream,_code,_code.Count);
                        var chunk = {
                            Arguments = _args,
                            Code = _code
                        };
                        this.Chunks.Add(chunk);
                    }
                }
                else if(hdrStr == "FUNS")
                {
                    var funLen = this.EnsureInt(stream);
                    for(var j = 0; j < funLen; j++)
                    {
                        var fnPartsCount = this.EnsureInt(stream);
                        var documentation = "";
                        var fnParts = [];
                        for(var k = 0; k < fnPartsCount; k++)
                        {
                            if(k == 0) documentation = this.GetString(stream);
                            else fnParts.Add(this.GetString(stream));
                        }
                        var fnId = this.EnsureInt(stream);
                        this.Functions.Add({
                            Documentation=documentation,
                            FunctionNameParts = fnParts,
                            Closure = fnId
                        });
                    }
                }
                else if(hdrStr == "STRS")
                {
                    var strcnt = this.EnsureInt(stream);
                    for(var j = 0; j < strcnt; j++)
                    {
                        this.Strings.Add(this.EnsureString(stream));
                    }
                }
                else {
                    var data = ByteArray(tableLength);
                    this.Ensure(stream,data,data.Count);
                    this.Sections.Add({
                        Name=hdrStr,
                        Data = data
                    });
                }
            }
        }
    };
}