// This module provides methods for creating nodes and relationships according
// to a defined schema.

package lib

import (
	"fmt"
)

// ========================================
// Schema Match Keys
// ========================================

func NewMatchKeys() *MatchKeys {
	return &MatchKeys{
		keys: map[string][]string{
			"User":  {"pubkey"},
			"Relay": {"url"},
			"Event": {"id"},
			"Tag":   {"name", "value"},
		},
	}
}

// ========================================
// Node Constructors
// ========================================

func NewUserNode(pubkey string) *Node {
	return NewNode("User", Properties{"pubkey": pubkey})
}

func NewRelayNode(url string) *Node {
	return NewNode("Relay", Properties{"url": url})
}

func NewEventNode(id string) *Node {
	return NewNode("Event", Properties{"id": id})
}

func NewTagNode(name string, value string) *Node {
	return NewNode("Tag", Properties{"name": name, "value": value})
}

// ========================================
// Relationship Constructors
// ========================================

func NewSignedRel(
	start *Node, end *Node, props Properties) *Relationship {
	return NewRelationshipWithValidation(
		"SIGNED", "User", "Event", start, end, props)

}

func NewTaggedRel(
	start *Node, end *Node, props Properties) *Relationship {
	return NewRelationshipWithValidation(
		"TAGGED", "Event", "Tag", start, end, props)
}

// ========================================
// Relationship Constructor Helpers
// ========================================

func validateNodeLabel(node *Node, role string, expectedLabel string) {
	if !node.Labels.Contains(expectedLabel) {
		panic(fmt.Errorf(
			"expected %s node to have label '%s'. got %v",
			role, expectedLabel, node.Labels.ToArray(),
		),
		)
	}
}

func NewRelationshipWithValidation(
	rtype string,
	startLabel string,
	endLabel string,
	start *Node,
	end *Node,
	props Properties) *Relationship {

	validateNodeLabel(start, "start", startLabel)
	validateNodeLabel(end, "end", endLabel)

	return NewRelationship(rtype, start, end, props)
}