predicates.go

package yit

import (
	"strings"

	"gopkg.in/yaml.v3"
)

var (
	All = func(node *yaml.Node) bool {
		return true
	}

	None = func(node *yaml.Node) bool {
		return false
	}

	StringValue = Intersect(
		WithKind(yaml.ScalarNode),
		WithShortTag("!!str"),
	)
)

func Intersect(ps ...Predicate) Predicate {
	return func(node *yaml.Node) bool {
		for _, p := range ps {
			if !p(node) {
				return false
			}
		}
		return true
	}
}

func Union(ps ...Predicate) Predicate {
	return func(node *yaml.Node) bool {
		for _, p := range ps {
			if p(node) {
				return true
			}
		}
		return false
	}
}

func Negate(p Predicate) Predicate {
	return func(node *yaml.Node) bool {
		return !p(node)
	}
}

func WithStringValue(value string) Predicate {
	return Intersect(
		StringValue,
		func(node *yaml.Node) bool {
			return node.Value == value
		},
	)
}

func WithShortTag(tag string) Predicate {
	return func(node *yaml.Node) bool {
		return node.ShortTag() == tag
	}
}

func WithValue(value string) Predicate {
	return func(node *yaml.Node) bool {
		return node.Value == value
	}
}

func WithKind(kind yaml.Kind) Predicate {
	return func(node *yaml.Node) bool {
		return node.Kind == kind
	}
}

func WithMapKey(key string) Predicate {
	return func(node *yaml.Node) bool {
		return FromNode(node).MapKeys().AnyMatch(WithValue(key))
	}
}

func WithMapValue(value string) Predicate {
	return func(node *yaml.Node) bool {
		return FromNode(node).MapValues().AnyMatch(WithValue(value))
	}
}

func WithMapKeyValue(keyPredicate, valuePredicate Predicate) Predicate {
	return Intersect(
		WithKind(yaml.MappingNode),
		func(node *yaml.Node) bool {
			for i := 0; i < len(node.Content); i += 2 {
				key := node.Content[i]
				value := node.Content[i+1]
				if keyPredicate(key) && valuePredicate(value) {
					return true
				}
			}
			return false
		},
	)
}

func WithPrefix(prefix string) Predicate {
	return func(node *yaml.Node) bool {
		return strings.HasPrefix(node.Value, prefix)
	}
}

func WithSuffix(suffix string) Predicate {
	return func(node *yaml.Node) bool {
		return strings.HasSuffix(node.Value, suffix)
	}
}