first commit

2023-06-01 08:41:54 +08:00
parent 61b0e99833
commit d253ed8d5b
80 changed files with 14245 additions and 0 deletions
@@ -0,0 +1,109 @@
+package core
+
+import (
+	"errors"
+
+	"github.com/dop251/goja"
+)
+
+func Buffer(vm *goja.Runtime, call goja.ConstructorCall) *goja.Object {
+	var buffer []byte
+	switch arg := call.Arguments[0].Export().(type) {
+	case string:
+		buffer = []byte(arg)
+	case []byte:
+		buffer = arg
+	case int:
+		buffer = make([]byte, arg)
+	case int64:
+		buffer = make([]byte, arg)
+	default:
+		panic(vm.NewTypeError("invalid argument type"))
+	}
+	obj := call.This.ToObject(vm)
+	obj.Set("length", func() int {
+		return len(buffer)
+	})
+
+	obj.Set("write", func(value interface{}, offset int, length int) {
+		var buf []byte
+		switch value := value.(type) {
+		case string:
+			buf = []byte(value)
+		case []byte:
+			buf = value
+		default:
+			panic(vm.NewTypeError("invalid argument type"))
+		}
+
+		if offset+length > len(buffer) {
+			panic(vm.NewGoError(errors.New("out of range")))
+		}
+
+		copy(buffer[offset:], buf[:length])
+	})
+
+	obj.Set("toString", func() string {
+		return string(buffer)
+	})
+
+	obj.Set("slice", func(start int, end int) []byte {
+		if start < 0 {
+			start += len(buffer)
+		}
+		if end < 0 {
+			end += len(buffer)
+		}
+		if end > len(buffer) {
+			end = len(buffer)
+		}
+		if start >= end || start >= len(buffer) {
+			return nil
+		}
+		return buffer[start:end]
+	})
+
+	obj.Set("copy", func(target []byte, sourceStart int, targetStart int, sourceEnd int) int {
+		if sourceStart < 0 {
+			sourceStart += len(buffer)
+		}
+		if sourceEnd < 0 {
+			sourceEnd += len(buffer)
+		}
+		if targetStart < 0 {
+			targetStart += len(target)
+		}
+		if sourceEnd > len(buffer) {
+			sourceEnd = len(buffer)
+		}
+		if sourceStart >= sourceEnd || sourceStart >= len(buffer) {
+			return 0
+		}
+		return copy(target[targetStart:], buffer[sourceStart:sourceEnd])
+	})
+
+	obj.Set("join", func(sep []byte, buffers ...[]byte) []byte {
+		var totalLen int
+		for _, buf := range buffers {
+			totalLen += len(buf)
+		}
+		if len(sep) > 0 && len(buffers) > 1 {
+			totalLen += len(sep) * (len(buffers) - 1)
+		}
+
+		result := make([]byte, totalLen)
+		offset := 0
+		for i, buf := range buffers {
+			copy(result[offset:], buf)
+			offset += len(buf)
+			if i < len(buffers)-1 && len(sep) > 0 {
+				copy(result[offset:], sep)
+				offset += len(sep)
+			}
+		}
+
+		return result
+	})
+
+	return call.This
+}