go-pkg-xmlx/src/node.go

package xmlx

import "os"
import "strings"
import "xml"
import "fmt"
import "strconv"

const (
	NT_ROOT      = 0x00
	NT_DIRECTIVE = 0x01
	NT_PROCINST  = 0x02
	NT_COMMENT   = 0x03
	NT_ELEMENT   = 0x04
)

type Attr struct {
	Name  xml.Name
	Value string
}

type Node struct {
	Type       byte
	Name       xml.Name
	Children   []*Node
	Attributes []Attr
	Parent     *Node
	Value      string
	Target     string // procinst field
}

func NewNode(tid byte) *Node { return &Node{Type: tid} }

// This wraps the standard xml.Unmarshal function and supplies this particular
// node as the content to be unmarshalled.
func (this *Node) Unmarshal(obj interface{}) os.Error {
	return xml.Unmarshal(strings.NewReader(this.String()), obj)
}

// Get node value as string
func (this *Node) GetValue(namespace, name string) string {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return ""
	}
	return node.Value
}

// Get node value as int
func (this *Node) GetValuei(namespace, name string) int {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atoi(node.Value)
	return n
}

// Get node value as int64
func (this *Node) GetValuei64(namespace, name string) int64 {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atoi64(node.Value)
	return n
}

// Get node value as uint
func (this *Node) GetValueui(namespace, name string) uint {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atoui(node.Value)
	return n
}

// Get node value as uint64
func (this *Node) GetValueui64(namespace, name string) uint64 {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atoui64(node.Value)
	return n
}

// Get node value as float
func (this *Node) GetValuef(namespace, name string) float {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atof(node.Value)
	return n
}

// Get node value as float32
func (this *Node) GetValuef32(namespace, name string) float32 {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atof32(node.Value)
	return n
}

// Get node value as float64
func (this *Node) GetValuef64(namespace, name string) float64 {
	node := rec_SelectNode(this, namespace, name)
	if node == nil {
		return 0
	}
	if node.Value == "" {
		return 0
	}
	n, _ := strconv.Atof64(node.Value)
	return n
}

// Get attribute value as string
func (this *Node) GetAttr(namespace, name string) string {
	for _, v := range this.Attributes {
		if namespace == v.Name.Space && name == v.Name.Local {
			return v.Value
		}
	}
	return ""
}

// Get attribute value as int
func (this *Node) GetAttri(namespace, name string) int {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atoi(s)
	return n
}

// Get attribute value as uint
func (this *Node) GetAttrui(namespace, name string) uint {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atoui(s)
	return n
}

// Get attribute value as uint64
func (this *Node) GetAttrui64(namespace, name string) uint64 {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atoui64(s)
	return n
}

// Get attribute value as int64
func (this *Node) GetAttri64(namespace, name string) int64 {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atoi64(s)
	return n
}

// Get attribute value as float
func (this *Node) GetAttrf(namespace, name string) float {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atof(s)
	return n
}

// Get attribute value as float32
func (this *Node) GetAttrf32(namespace, name string) float32 {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atof32(s)
	return n
}

// Get attribute value as float64
func (this *Node) GetAttrf64(namespace, name string) float64 {
	s := this.GetAttr(namespace, name)
	if s == "" {
		return 0
	}
	n, _ := strconv.Atof64(s)
	return n
}

// Returns true if this node has the specified attribute. False otherwise.
func (this *Node) HasAttr(namespace, name string) bool {
	for _, v := range this.Attributes {
		if namespace == v.Name.Space && name == v.Name.Local {
			return true
		}
	}
	return false
}

// Select single node by name
func (this *Node) SelectNode(namespace, name string) *Node {
	return rec_SelectNode(this, namespace, name)
}

func rec_SelectNode(cn *Node, namespace, name string) *Node {
	if cn.Name.Space == namespace && cn.Name.Local == name {
		return cn
	}

	for _, v := range cn.Children {
		tn := rec_SelectNode(v, namespace, name)
		if tn != nil {
			return tn
		}
	}
	return nil
}

// Select multiple nodes by name
func (this *Node) SelectNodes(namespace, name string) []*Node {
	list := make([]*Node, 0)
	rec_SelectNodes(this, namespace, name, &list)
	return list
}

func rec_SelectNodes(cn *Node, namespace, name string, list *[]*Node) {
	if cn.Name.Space == namespace && cn.Name.Local == name {
		c := make([]*Node, len(*list)+1)
		copy(c, *list)
		c[len(c)-1] = cn
		*list = c
		return
	}

	for _, v := range cn.Children {
		rec_SelectNodes(v, namespace, name, list)
	}
}

// Convert node to appropriate string representation based on it's @Type.
// Note that NT_ROOT is a special-case empty node used as the root for a
// Document. This one has no representation by itself. It merely forwards the
// String() call to it's child nodes.
func (this *Node) String() (s string) {
	switch this.Type {
	case NT_PROCINST:
		s = this.printProcInst()
	case NT_COMMENT:
		s = this.printComment()
	case NT_DIRECTIVE:
		s = this.printDirective()
	case NT_ELEMENT:
		s = this.printElement()
	case NT_ROOT:
		s = this.printRoot()
	}
	return
}

func (this *Node) printRoot() (s string) {
	for _, v := range this.Children {
		s += v.String()
	}
	return
}

func (this *Node) printProcInst() (s string) {
	s = "<?" + this.Target + " " + this.Value + "?>"
	return
}

func (this *Node) printComment() (s string) {
	s = "<!-- " + this.Value + " -->"
	return
}

func (this *Node) printDirective() (s string) {
	s = "<!" + this.Value + "!>"
	return
}

func (this *Node) printElement() (s string) {
	if len(this.Name.Space) > 0 {
		s = "<" + this.Name.Space + ":" + this.Name.Local
	} else {
		s = "<" + this.Name.Local
	}

	for _, v := range this.Attributes {
		if len(v.Name.Space) > 0 {
			s += fmt.Sprintf(` %s:%s="%s"`, v.Name.Space, v.Name.Local, v.Value)
		} else {
			s += fmt.Sprintf(` %s="%s"`, v.Name.Local, v.Value)
		}
	}

	if len(this.Children) == 0 && len(this.Value) == 0 {
		s += " />"
		return
	}

	s += ">"

	for _, v := range this.Children {
		s += v.String()
	}

	s += this.Value
	if len(this.Name.Space) > 0 {
		s += "</" + this.Name.Space + ":" + this.Name.Local + ">"
	} else {
		s += "</" + this.Name.Local + ">"
	}
	return
}

// Add a child node
func (this *Node) AddChild(t *Node) {
	if t.Parent != nil {
		t.Parent.RemoveChild(t)
	}
	t.Parent = this

	c := make([]*Node, len(this.Children)+1)
	copy(c, this.Children)
	c[len(c)-1] = t
	this.Children = c
}

// Remove a child node
func (this *Node) RemoveChild(t *Node) {
	p := -1
	for i, v := range this.Children {
		if v == t {
			p = i
			break
		}
	}

	if p == -1 {
		return
	}

	c := make([]*Node, len(this.Children)-1)
	copy(c, this.Children[0:p])
	copy(c[p:], this.Children[p+1:])
	this.Children = c

	t.Parent = nil
}