package structmapper

import (
	"fmt"
	"sync"

	exception "git.apihub24.de/admin/exception"
	di "git.apihub24.de/admin/generic-di"
)

func init() {
	di.Injectable(newMapperRegistry)
}

var (
	MappingStrategyNotFound  = exception.NewCustom("MappingStrategyNotFound")
	StrategyRuntimeException = exception.NewCustom("StrategyRuntimeException")
)

func newMapperRegistry() *mapperRegistry {
	return &mapperRegistry{
		strategies: map[string]func(any) (any, error){},
		mu:         sync.Mutex{},
	}
}

type mapperRegistry struct {
	strategies map[string]func(any) (any, error)
	mu         sync.Mutex
}

func (registry *mapperRegistry) Run(key string, value any) (any, error) {
	strategy, ok := registry.strategies[key]
	if !ok {
		return nil, MappingStrategyNotFound.With(fmt.Errorf("strategy key %s", key))
	}
	var err error
	resultRef, err := strategy(value)
	if err != nil {
		return nil, StrategyRuntimeException.With(err)
	}
	return resultRef, nil
}

func (registry *mapperRegistry) RegisterStrategy(key string, strategy func(any) (any, error)) {
	registry.mu.Lock()
	defer registry.mu.Unlock()

	registry.strategies[key] = strategy
}

func (registry *mapperRegistry) UnregisterStrategy(key string) {
	registry.mu.Lock()
	defer registry.mu.Unlock()

	delete(registry.strategies, key)
}