package storage

import (
	"context"
	"sync"
	"time"

	slurpContext "chorus/pkg/slurp/context"
	"chorus/pkg/ucxl"
)

// inMemoryContextStore offers a lightweight ContextStore implementation suitable for
// local development and SEC-SLURP bootstrap scenarios. It keeps all context nodes in
// process memory, providing the minimal surface required by the temporal subsystem until
// the production storage stack is wired in.
type inMemoryContextStore struct {
	mu       sync.RWMutex
	contexts map[string]*slurpContext.ContextNode
}

// NewInMemoryContextStore constructs an in-memory ContextStore.
func NewInMemoryContextStore() ContextStore {
	return &inMemoryContextStore{
		contexts: make(map[string]*slurpContext.ContextNode),
	}
}

func (s *inMemoryContextStore) StoreContext(ctx context.Context, node *slurpContext.ContextNode, roles []string) error {
	if node == nil {
		return nil
	}
	s.mu.Lock()
	defer s.mu.Unlock()
	s.contexts[node.UCXLAddress.String()] = node
	return nil
}

func (s *inMemoryContextStore) RetrieveContext(ctx context.Context, address ucxl.Address, role string) (*slurpContext.ContextNode, error) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	node, ok := s.contexts[address.String()]
	if !ok {
		return nil, ErrNotFound
	}
	return node, nil
}

func (s *inMemoryContextStore) UpdateContext(ctx context.Context, node *slurpContext.ContextNode, roles []string) error {
	if node == nil {
		return nil
	}
	s.mu.Lock()
	defer s.mu.Unlock()
	s.contexts[node.UCXLAddress.String()] = node
	return nil
}

func (s *inMemoryContextStore) DeleteContext(ctx context.Context, address ucxl.Address) error {
	s.mu.Lock()
	defer s.mu.Unlock()
	delete(s.contexts, address.String())
	return nil
}

func (s *inMemoryContextStore) ExistsContext(ctx context.Context, address ucxl.Address) (bool, error) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	_, ok := s.contexts[address.String()]
	return ok, nil
}

func (s *inMemoryContextStore) ListContexts(ctx context.Context, criteria *ListCriteria) ([]*slurpContext.ContextNode, error) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	results := make([]*slurpContext.ContextNode, 0, len(s.contexts))
	for _, node := range s.contexts {
		results = append(results, node)
	}
	return results, nil
}

func (s *inMemoryContextStore) SearchContexts(ctx context.Context, query *SearchQuery) (*SearchResults, error) {
	return &SearchResults{
		Results:        []*SearchResult{},
		TotalResults:   0,
		ProcessingTime: 0,
		Facets:         map[string]map[string]int{},
		Suggestions:    []string{},
		ProcessedAt:    time.Now(),
	}, nil
}

func (s *inMemoryContextStore) BatchStore(ctx context.Context, batch *BatchStoreRequest) (*BatchStoreResult, error) {
	if batch == nil {
		return &BatchStoreResult{}, nil
	}
	s.mu.Lock()
	defer s.mu.Unlock()
	success := 0
	for _, item := range batch.Contexts {
		if item == nil || item.Context == nil {
			continue
		}
		s.contexts[item.Context.UCXLAddress.String()] = item.Context
		success++
	}
	return &BatchStoreResult{SuccessCount: success}, nil
}

func (s *inMemoryContextStore) BatchRetrieve(ctx context.Context, batch *BatchRetrieveRequest) (*BatchRetrieveResult, error) {
	result := &BatchRetrieveResult{
		Contexts:       make(map[string]*slurpContext.ContextNode),
		Errors:         make(map[string]error),
		ProcessedAt:    time.Now(),
		ProcessingTime: 0,
	}
	if batch == nil {
		return result, nil
	}
	s.mu.RLock()
	defer s.mu.RUnlock()
	for _, address := range batch.Addresses {
		key := address.String()
		if node, ok := s.contexts[key]; ok {
			result.Contexts[key] = node
			result.SuccessCount++
		} else {
			result.Errors[key] = ErrNotFound
			result.ErrorCount++
		}
	}
	return result, nil
}

func (s *inMemoryContextStore) GetStorageStats(ctx context.Context) (*StorageStatistics, error) {
	s.mu.RLock()
	defer s.mu.RUnlock()
	return &StorageStatistics{
		TotalContexts: int64(len(s.contexts)),
		LocalContexts: int64(len(s.contexts)),
		LastSyncTime:  time.Now(),
	}, nil
}

func (s *inMemoryContextStore) Sync(ctx context.Context) error {
	return nil
}

func (s *inMemoryContextStore) Backup(ctx context.Context, destination string) error {
	return nil
}

func (s *inMemoryContextStore) Restore(ctx context.Context, source string) error {
	return nil
}