package client

import (
	"context"
	"encoding/json"
	"fmt"

	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/pkg/service/control"
	controlSvc "git.frostfs.info/TrueCloudLab/frostfs-s3-gw/pkg/service/control/server"
	policyengine "git.frostfs.info/TrueCloudLab/policy-engine"
	engineiam "git.frostfs.info/TrueCloudLab/policy-engine/iam"
	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
	"go.uber.org/zap"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

type Client struct {
	svc control.ControlServiceClient
	key *keys.PrivateKey
}

type Config struct {
	Logger *zap.Logger
}

func New(ctx context.Context, addr string, key *keys.PrivateKey) (*Client, error) {
	conn, err := grpc.Dial(addr, grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		return nil, fmt.Errorf("failed to dial s3 gw control api: %w", err)
	}

	svc := control.NewControlServiceClient(conn)

	// todo consider add invoking healthcheck
	// c.Healthcheck(ctx)

	return &Client{
		svc: svc,
		key: key,
	}, nil
}

func (c *Client) Healthcheck(ctx context.Context) error {
	req := &control.HealthCheckRequest{}
	sig, err := controlSvc.SignMessage(&c.key.PrivateKey, req.Body)
	if err != nil {
		return err
	}
	req.Signature = sig

	res, err := c.svc.HealthCheck(ctx, req)
	if err != nil {
		return err
	}

	if res.Body.HealthStatus != control.HealthStatus_READY {
		return fmt.Errorf("service isn't ready, status: %s", res.Body.HealthStatus)
	}

	return nil
}

func (c *Client) AddPolicyIAM(ctx context.Context, policy string) error {
	var p engineiam.Policy
	if err := json.Unmarshal([]byte(policy), &p); err != nil {
		return err
	}

	chain, err := p.ToChain()
	if err != nil {
		return err
	}

	return c.AddPolicy(ctx, chain)
}

func (c *Client) AddPolicy(ctx context.Context, chain *policyengine.Chain) error {
	req := &control.AddPolicyRequest{
		Body: chain.Bytes(),
	}

	sig, err := controlSvc.SignMessage(&c.key.PrivateKey, req.Body)
	if err != nil {
		return err
	}
	req.Signature = sig

	_, err = c.svc.AddPolicy(ctx, req)
	return err
}