package console

import (
	"context"
	"errors"
	"sync"

	"github.com/carlosframework/platform/internal/release"
)

// hookStore is the recording store the lifecycle tests drive failures
// through. failPut and failDelete map a key to how many more times it fails
// (a negative count fails forever); onDelete runs before each Delete, which is
// how a test observes the row at the moment a marker is removed; onGet runs
// before each Get.
type hookStore struct {
	release.Store
	mu         sync.Mutex
	failPut    map[string]int
	failDelete map[string]int
	onDelete   func(key string)
	// onGet runs before each Get: how a test changes the bucket between two
	// reads of one request (Task 8's ErrNotTrashed test).
	onGet   func(key string)
	deletes []string
}

func (h *hookStore) Get(ctx context.Context, key string) ([]byte, string, error) {
	if h.onGet != nil {
		h.onGet(key)
	}
	return h.Store.Get(ctx, key)
}

func (h *hookStore) fails(m map[string]int, key string) bool {
	h.mu.Lock()
	defer h.mu.Unlock()
	n, ok := m[key]
	if !ok || n == 0 {
		return false
	}
	if n > 0 {
		m[key] = n - 1
	}
	return true
}

func (h *hookStore) Put(ctx context.Context, key string, body []byte, ifMatch string) (string, error) {
	if h.fails(h.failPut, key) {
		return "", errors.New("hookStore: put refused")
	}
	return h.Store.Put(ctx, key, body, ifMatch)
}

func (h *hookStore) Delete(ctx context.Context, key string) error {
	if h.onDelete != nil {
		h.onDelete(key)
	}
	if h.fails(h.failDelete, key) {
		return errors.New("hookStore: delete refused")
	}
	h.mu.Lock()
	h.deletes = append(h.deletes, key)
	h.mu.Unlock()
	return h.Store.Delete(ctx, key)
}