package entry

import (
	"RenewCMS/internal/domain/contenttype"
	"reflect"
	"sort"
)

func SameValue(left any, right any) bool {
	return reflect.DeepEqual(left, right)
}

type UniqueValue struct {
	Key   string
	Value any
}

func ApplyDefaults(fields []contenttype.Field, data map[string]any) map[string]any {
	filled := make(map[string]any, len(data))
	for key, value := range data {
		filled[key] = value
	}
	for _, field := range fields {
		if _, present := filled[field.Key]; !present && field.Default != nil {
			filled[field.Key] = field.Default
		}
	}
	return filled
}

func Project(fields []contenttype.Field, data map[string]any) map[string]any {
	projected := make(map[string]any, len(data))
	for _, field := range fields {
		if value, present := data[field.Key]; present {
			projected[field.Key] = value
		}
	}
	return projected
}

func Validate(fields []contenttype.Field, data map[string]any) error {
	for _, field := range fields {
		if err := validateField(field, data); err != nil {
			return err
		}
	}
	return firstUnknownField(fields, data)
}

func validateField(field contenttype.Field, data map[string]any) error {
	value := data[field.Key]
	if value == nil {
		if field.Required {
			return invalidField(field.Key, RuleRequired)
		}
		return nil
	}
	if rule := field.Violation(value); rule != "" {
		return invalidField(field.Key, rule)
	}
	return nil
}

func firstUnknownField(fields []contenttype.Field, data map[string]any) error {
	known := make(map[string]bool, len(fields))
	for _, field := range fields {
		known[field.Key] = true
	}
	var unknown []string
	for key := range data {
		if !known[key] {
			unknown = append(unknown, key)
		}
	}
	if len(unknown) == 0 {
		return nil
	}
	sort.Strings(unknown)
	return invalidField(unknown[0], RuleUnknownField)
}

func UniqueValues(fields []contenttype.Field, data map[string]any) []UniqueValue {
	var values []UniqueValue
	for _, field := range fields {
		if value := data[field.Key]; field.Unique && value != nil {
			values = append(values, UniqueValue{Key: field.Key, Value: value})
		}
	}
	return values
}