nix-amer/internal/cnf/bash.go

100 lines
2.0 KiB
Go

package cnf
import (
lib "github.com/xdrm-brackets/nix-amer/internal/cnf/parser/bash"
"io"
"strings"
)
type bash struct {
data *lib.File
parsed bool
}
// ReadFrom implements io.ReaderFrom
func (d *bash) ReadFrom(_reader io.Reader) (int64, error) {
d.data = new(lib.File)
// 1. get bash decoder
decoder := lib.NewDecoder(_reader)
err := decoder.Decode(d.data)
if err != nil {
return 0, err
}
d.parsed = true
return 0, nil
}
// WriteTo implements io.WriterTo
func (d *bash) WriteTo(_writer io.Writer) (int64, error) {
encoder := lib.NewEncoder(_writer)
return 0, encoder.Encode(d.data)
}
// browse returns the target of a dot-separated path (as an interface{} chain where the last is the target if found)
// if <create> is true, create if does not exist
func (d *bash) browse(_path string, create ...bool) (*lib.Line, bool) {
mustCreate := len(create) > 0 && create[0]
// 1. extract path
path := strings.Split(_path, ".")
field := path[len(path)-1]
// 2. nothing
if len(path) < 1 {
return &lib.Line{}, true
}
// 3. iterate over path / nested fields
for _, line := range d.data.Lines {
if line.Type == lib.ASSIGNMENT && len(line.Components) > 1 && line.Components[1] == field {
return line, true
}
}
// 4. create assignment
if mustCreate {
assignment := &lib.Line{
Type: lib.ASSIGNMENT,
Components: []string{"", field, "", ""},
}
d.data.Lines = append(d.data.Lines, assignment)
return assignment, true
}
return nil, false
}
// Get returns the value of a dot-separated path, and if it exists
func (d *bash) Get(_path string) (string, bool) {
// 1. browse path
last, found := d.browse(_path, true)
if !found {
return "", false
}
// 2. Get last field
return last.Components[2], true
}
// Set the value of a dot-separated path, and creates it if not found
func (d *bash) Set(_path, _value string) bool {
// 1. browse path
last, found := d.browse(_path, true)
if !found {
return false
}
// 2. Set value
last.Components[2] = _value
return true
}