package main

import (
	"sync"

	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/container"
	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine"
	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine/inmemory"
)

type apeChainSourceImpl struct {
	mtx               sync.Mutex
	localChainStorage map[cid.ID]engine.LocalOverrideEngine
}

func NewAPESource() container.AccessPolicyEngineChainSource {
	return &apeChainSourceImpl{
		localChainStorage: make(map[cid.ID]engine.LocalOverrideEngine),
	}
}

var _ container.AccessPolicyEngineChainSource = (*apeChainSourceImpl)(nil)

func (c *apeChainSourceImpl) GetChainSource(cid cid.ID) (engine.LocalOverrideEngine, error) {
	c.mtx.Lock()
	defer c.mtx.Unlock()

	s, ok := c.localChainStorage[cid]
	if ok {
		return s, nil
	}
	c.localChainStorage[cid] = inmemory.NewInMemoryLocalOverrides()
	return c.localChainStorage[cid], nil
}