terraform/vendor/github.com/ChrisTrenkamp/goxpath/internal/execxp/paths.go

398 lines
7.7 KiB
Go

package execxp
import (
"encoding/xml"
"fmt"
"strconv"
"strings"
"github.com/ChrisTrenkamp/goxpath/internal/parser"
"github.com/ChrisTrenkamp/goxpath/internal/parser/findutil"
"github.com/ChrisTrenkamp/goxpath/internal/parser/intfns"
"github.com/ChrisTrenkamp/goxpath/internal/xconst"
"github.com/ChrisTrenkamp/goxpath/internal/xsort"
"github.com/ChrisTrenkamp/goxpath/internal/lexer"
"github.com/ChrisTrenkamp/goxpath/internal/parser/pathexpr"
"github.com/ChrisTrenkamp/goxpath/tree"
)
type xpFilt struct {
t tree.Node
ctx tree.Result
expr pathexpr.PathExpr
ns map[string]string
ctxPos int
ctxSize int
proxPos map[int]int
fns map[xml.Name]tree.Wrap
variables map[string]tree.Result
}
type xpExecFn func(*xpFilt, string)
var xpFns = map[lexer.XItemType]xpExecFn{
lexer.XItemAbsLocPath: xfAbsLocPath,
lexer.XItemAbbrAbsLocPath: xfAbbrAbsLocPath,
lexer.XItemRelLocPath: xfRelLocPath,
lexer.XItemAbbrRelLocPath: xfAbbrRelLocPath,
lexer.XItemAxis: xfAxis,
lexer.XItemAbbrAxis: xfAbbrAxis,
lexer.XItemNCName: xfNCName,
lexer.XItemQName: xfQName,
lexer.XItemNodeType: xfNodeType,
lexer.XItemProcLit: xfProcInstLit,
lexer.XItemStrLit: xfStrLit,
lexer.XItemNumLit: xfNumLit,
}
func xfExec(f *xpFilt, n *parser.Node) (err error) {
for n != nil {
if fn, ok := xpFns[n.Val.Typ]; ok {
fn(f, n.Val.Val)
n = n.Left
} else if n.Val.Typ == lexer.XItemPredicate {
if err = xfPredicate(f, n.Left); err != nil {
return
}
n = n.Right
} else if n.Val.Typ == lexer.XItemFunction {
if err = xfFunction(f, n); err != nil {
return
}
n = n.Right
} else if n.Val.Typ == lexer.XItemOperator {
lf := xpFilt{
t: f.t,
ns: f.ns,
ctx: f.ctx,
ctxPos: f.ctxPos,
ctxSize: f.ctxSize,
proxPos: f.proxPos,
fns: f.fns,
variables: f.variables,
}
left, err := exec(&lf, n.Left)
if err != nil {
return err
}
rf := xpFilt{
t: f.t,
ns: f.ns,
ctx: f.ctx,
fns: f.fns,
variables: f.variables,
}
right, err := exec(&rf, n.Right)
if err != nil {
return err
}
return xfOperator(left, right, f, n.Val.Val)
} else if n.Val.Typ == lexer.XItemVariable {
if res, ok := f.variables[n.Val.Val]; ok {
f.ctx = res
return nil
}
return fmt.Errorf("Invalid variable '%s'", n.Val.Val)
} else if string(n.Val.Typ) == "" {
n = n.Left
//} else {
// return fmt.Errorf("Cannot process " + string(n.Val.Typ))
}
}
return
}
func xfPredicate(f *xpFilt, n *parser.Node) (err error) {
res := f.ctx.(tree.NodeSet)
newRes := make(tree.NodeSet, 0, len(res))
for i := range res {
pf := xpFilt{
t: f.t,
ns: f.ns,
ctxPos: i,
ctxSize: f.ctxSize,
ctx: tree.NodeSet{res[i]},
fns: f.fns,
variables: f.variables,
}
predRes, err := exec(&pf, n)
if err != nil {
return err
}
ok, err := checkPredRes(predRes, f, res[i])
if err != nil {
return err
}
if ok {
newRes = append(newRes, res[i])
}
}
f.proxPos = make(map[int]int)
for pos, j := range newRes {
f.proxPos[j.Pos()] = pos + 1
}
f.ctx = newRes
f.ctxSize = len(newRes)
return
}
func checkPredRes(ret tree.Result, f *xpFilt, node tree.Node) (bool, error) {
if num, ok := ret.(tree.Num); ok {
if float64(f.proxPos[node.Pos()]) == float64(num) {
return true, nil
}
return false, nil
}
if b, ok := ret.(tree.IsBool); ok {
return bool(b.Bool()), nil
}
return false, fmt.Errorf("Cannot convert argument to boolean")
}
func xfFunction(f *xpFilt, n *parser.Node) error {
spl := strings.Split(n.Val.Val, ":")
var name xml.Name
if len(spl) == 1 {
name.Local = spl[0]
} else {
name.Space = f.ns[spl[0]]
name.Local = spl[1]
}
fn, ok := intfns.BuiltIn[name]
if !ok {
fn, ok = f.fns[name]
}
if ok {
args := []tree.Result{}
param := n.Left
for param != nil {
pf := xpFilt{
t: f.t,
ctx: f.ctx,
ns: f.ns,
ctxPos: f.ctxPos,
ctxSize: f.ctxSize,
fns: f.fns,
variables: f.variables,
}
res, err := exec(&pf, param.Left)
if err != nil {
return err
}
args = append(args, res)
param = param.Right
}
filt, err := fn.Call(tree.Ctx{NodeSet: f.ctx.(tree.NodeSet), Size: f.ctxSize, Pos: f.ctxPos + 1}, args...)
f.ctx = filt
return err
}
return fmt.Errorf("Unknown function: %s", n.Val.Val)
}
var eqOps = map[string]bool{
"=": true,
"!=": true,
}
var booleanOps = map[string]bool{
"=": true,
"!=": true,
"<": true,
"<=": true,
">": true,
">=": true,
}
var numOps = map[string]bool{
"*": true,
"div": true,
"mod": true,
"+": true,
"-": true,
"=": true,
"!=": true,
"<": true,
"<=": true,
">": true,
">=": true,
}
var andOrOps = map[string]bool{
"and": true,
"or": true,
}
func xfOperator(left, right tree.Result, f *xpFilt, op string) error {
if booleanOps[op] {
lNode, lOK := left.(tree.NodeSet)
rNode, rOK := right.(tree.NodeSet)
if lOK && rOK {
return bothNodeOperator(lNode, rNode, f, op)
}
if lOK {
return leftNodeOperator(lNode, right, f, op)
}
if rOK {
return rightNodeOperator(left, rNode, f, op)
}
if eqOps[op] {
return equalsOperator(left, right, f, op)
}
}
if numOps[op] {
return numberOperator(left, right, f, op)
}
if andOrOps[op] {
return andOrOperator(left, right, f, op)
}
//if op == "|" {
return unionOperator(left, right, f, op)
//}
//return fmt.Errorf("Unknown operator " + op)
}
func xfAbsLocPath(f *xpFilt, val string) {
i := f.t
for i.GetNodeType() != tree.NtRoot {
i = i.GetParent()
}
f.ctx = tree.NodeSet{i}
}
func xfAbbrAbsLocPath(f *xpFilt, val string) {
i := f.t
for i.GetNodeType() != tree.NtRoot {
i = i.GetParent()
}
f.ctx = tree.NodeSet{i}
f.expr = abbrPathExpr()
find(f)
}
func xfRelLocPath(f *xpFilt, val string) {
}
func xfAbbrRelLocPath(f *xpFilt, val string) {
f.expr = abbrPathExpr()
find(f)
}
func xfAxis(f *xpFilt, val string) {
f.expr.Axis = val
}
func xfAbbrAxis(f *xpFilt, val string) {
f.expr.Axis = xconst.AxisAttribute
}
func xfNCName(f *xpFilt, val string) {
f.expr.Name.Space = val
}
func xfQName(f *xpFilt, val string) {
f.expr.Name.Local = val
find(f)
}
func xfNodeType(f *xpFilt, val string) {
f.expr.NodeType = val
find(f)
}
func xfProcInstLit(f *xpFilt, val string) {
filt := tree.NodeSet{}
for _, i := range f.ctx.(tree.NodeSet) {
if i.GetToken().(xml.ProcInst).Target == val {
filt = append(filt, i)
}
}
f.ctx = filt
}
func xfStrLit(f *xpFilt, val string) {
f.ctx = tree.String(val)
}
func xfNumLit(f *xpFilt, val string) {
num, _ := strconv.ParseFloat(val, 64)
f.ctx = tree.Num(num)
}
func abbrPathExpr() pathexpr.PathExpr {
return pathexpr.PathExpr{
Name: xml.Name{},
Axis: xconst.AxisDescendentOrSelf,
NodeType: xconst.NodeTypeNode,
}
}
func find(f *xpFilt) {
dupFilt := make(map[int]tree.Node)
f.proxPos = make(map[int]int)
if f.expr.Axis == "" && f.expr.NodeType == "" && f.expr.Name.Space == "" {
if f.expr.Name.Local == "." {
f.expr = pathexpr.PathExpr{
Name: xml.Name{},
Axis: xconst.AxisSelf,
NodeType: xconst.NodeTypeNode,
}
}
if f.expr.Name.Local == ".." {
f.expr = pathexpr.PathExpr{
Name: xml.Name{},
Axis: xconst.AxisParent,
NodeType: xconst.NodeTypeNode,
}
}
}
f.expr.NS = f.ns
for _, i := range f.ctx.(tree.NodeSet) {
for pos, j := range findutil.Find(i, f.expr) {
dupFilt[j.Pos()] = j
f.proxPos[j.Pos()] = pos + 1
}
}
res := make(tree.NodeSet, 0, len(dupFilt))
for _, i := range dupFilt {
res = append(res, i)
}
xsort.SortNodes(res)
f.expr = pathexpr.PathExpr{}
f.ctxSize = len(res)
f.ctx = res
}