package client

import (
	"context"
	"fmt"

	v2netmap "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/netmap"
	rpcapi "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/rpc"
	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/rpc/client"
	v2session "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/session"
	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/signature"
	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/version"
)

// PrmEndpointInfo groups parameters of EndpointInfo operation.
type PrmEndpointInfo struct {
	XHeaders []string
}

func (x *PrmEndpointInfo) buildRequest(c *Client) (*v2netmap.LocalNodeInfoRequest, error) {
	meta := new(v2session.RequestMetaHeader)
	writeXHeadersToMeta(x.XHeaders, meta)

	req := new(v2netmap.LocalNodeInfoRequest)
	req.SetBody(new(v2netmap.LocalNodeInfoRequestBody))
	c.prepareRequest(req, meta)
	return req, nil
}

// ResEndpointInfo group resulting values of EndpointInfo operation.
type ResEndpointInfo struct {
	statusRes

	version version.Version

	ni netmap.NodeInfo
}

// LatestVersion returns latest FrostFS API protocol's version in use.
func (x ResEndpointInfo) LatestVersion() version.Version {
	return x.version
}

// NodeInfo returns information about the FrostFS node served on the remote endpoint.
func (x ResEndpointInfo) NodeInfo() netmap.NodeInfo {
	return x.ni
}

// EndpointInfo requests information about the storage node served on the remote endpoint.
//
// Method can be used as a health check to see if node is alive and responds to requests.
//
// Any client's internal or transport errors are returned as `error`.
// If PrmInit.DisableFrostFSFailuresResolution has been called, unsuccessful
// FrostFS status codes are included in the returned result structure,
// otherwise, are also returned as `error`.
//
// Returns an error if parameters are set incorrectly (see PrmEndpointInfo docs).
// Context is required and must not be nil. It is used for network communication.
//
// Exactly one return value is non-nil. Server status return is returned in ResEndpointInfo.
// Reflects all internal errors in second return value (transport problems, response processing, etc.).
//
// Return statuses:
//   - global (see Client docs).
func (c *Client) EndpointInfo(ctx context.Context, prm PrmEndpointInfo) (*ResEndpointInfo, error) {
	req, err := prm.buildRequest(c)
	if err != nil {
		return nil, err
	}

	if err := signature.SignServiceMessage(&c.prm.key, req); err != nil {
		return nil, fmt.Errorf("sign request: %w", err)
	}

	resp, err := rpcapi.LocalNodeInfo(&c.c, req, client.WithContext(ctx))
	if err != nil {
		return nil, err
	}

	var res ResEndpointInfo
	res.st, err = c.processResponse(resp)
	if err != nil || !apistatus.IsSuccessful(res.st) {
		return &res, err
	}

	body := resp.GetBody()

	const fieldVersion = "version"

	verV2 := body.GetVersion()
	if verV2 == nil {
		return nil, newErrMissingResponseField(fieldVersion)
	}
	if err := res.version.ReadFromV2(*verV2); err != nil {
		return nil, newErrInvalidResponseField(fieldVersion, err)
	}

	const fieldNodeInfo = "node info"

	nodeInfoV2 := body.GetNodeInfo()
	if nodeInfoV2 == nil {
		return nil, newErrMissingResponseField(fieldNodeInfo)
	}
	if err := res.ni.ReadFromV2(*nodeInfoV2); err != nil {
		return nil, newErrInvalidResponseField(fieldNodeInfo, err)
	}
	return &res, nil
}

// PrmNetworkInfo groups parameters of NetworkInfo operation.
type PrmNetworkInfo struct {
	XHeaders []string
}

func (x PrmNetworkInfo) buildRequest(c *Client) (*v2netmap.NetworkInfoRequest, error) {
	meta := new(v2session.RequestMetaHeader)
	writeXHeadersToMeta(x.XHeaders, meta)

	var req v2netmap.NetworkInfoRequest
	req.SetBody(new(v2netmap.NetworkInfoRequestBody))
	c.prepareRequest(&req, meta)
	return &req, nil
}

// ResNetworkInfo groups resulting values of NetworkInfo operation.
type ResNetworkInfo struct {
	statusRes

	info netmap.NetworkInfo
}

// Info returns structured information about the FrostFS network.
func (x ResNetworkInfo) Info() netmap.NetworkInfo {
	return x.info
}

// NetworkInfo requests information about the FrostFS network of which the remote server is a part.
//
// Any client's internal or transport errors are returned as `error`.
// If PrmInit.DisableFrostFSFailuresResolution has been called, unsuccessful
// FrostFS status codes are included in the returned result structure,
// otherwise, are also returned as `error`.
//
// Returns an error if parameters are set incorrectly (see PrmNetworkInfo docs).
// Context is required and must not be nil. It is used for network communication.
//
// Exactly one return value is non-nil. Server status return is returned in ResNetworkInfo.
// Reflects all internal errors in second return value (transport problems, response processing, etc.).
//
// Return statuses:
//   - global (see Client docs).
func (c *Client) NetworkInfo(ctx context.Context, prm PrmNetworkInfo) (*ResNetworkInfo, error) {
	req, err := prm.buildRequest(c)
	if err != nil {
		return nil, err
	}

	if err := signature.SignServiceMessage(&c.prm.key, req); err != nil {
		return nil, fmt.Errorf("sign request: %w", err)
	}

	resp, err := rpcapi.NetworkInfo(&c.c, req, client.WithContext(ctx))
	if err != nil {
		return nil, err
	}

	var res ResNetworkInfo
	res.st, err = c.processResponse(resp)
	if err != nil || !apistatus.IsSuccessful(res.st) {
		return &res, err
	}

	const fieldNetInfo = "network info"

	netInfoV2 := resp.GetBody().GetNetworkInfo()
	if netInfoV2 == nil {
		return nil, newErrMissingResponseField(fieldNetInfo)
	}
	if err := res.info.ReadFromV2(*netInfoV2); err != nil {
		return nil, newErrInvalidResponseField(fieldNetInfo, err)
	}
	return &res, nil
}

// PrmNetMapSnapshot groups parameters of NetMapSnapshot operation.
type PrmNetMapSnapshot struct {
}

// ResNetMapSnapshot groups resulting values of NetMapSnapshot operation.
type ResNetMapSnapshot struct {
	statusRes

	netMap netmap.NetMap
}

// NetMap returns current server's local network map.
func (x ResNetMapSnapshot) NetMap() netmap.NetMap {
	return x.netMap
}

// NetMapSnapshot requests current network view of the remote server.
//
// Any client's internal or transport errors are returned as `error`.
// If PrmInit.DisableFrostFSFailuresResolution has been called, unsuccessful
// FrostFS status codes are included in the returned result structure,
// otherwise, are also returned as `error`.
//
// Returns an error if parameters are set incorrectly.
// Context is required and MUST NOT be nil. It is used for network communication.
//
// Exactly one return value is non-nil. Server status return is returned in ResNetMapSnapshot.
// Reflects all internal errors in second return value (transport problems, response processing, etc.).
//
// Return statuses:
//   - global (see Client docs).
func (c *Client) NetMapSnapshot(ctx context.Context, _ PrmNetMapSnapshot) (*ResNetMapSnapshot, error) {
	// form request body
	var body v2netmap.SnapshotRequestBody

	// form meta header
	var meta v2session.RequestMetaHeader

	// form request
	var req v2netmap.SnapshotRequest
	req.SetBody(&body)
	c.prepareRequest(&req, &meta)

	err := signature.SignServiceMessage(&c.prm.key, &req)
	if err != nil {
		return nil, fmt.Errorf("sign request: %w", err)
	}

	resp, err := c.server.netMapSnapshot(ctx, req)
	if err != nil {
		return nil, err
	}

	var res ResNetMapSnapshot
	res.st, err = c.processResponse(resp)
	if err != nil {
		return nil, err
	}

	if !apistatus.IsSuccessful(res.st) {
		return &res, nil
	}

	const fieldNetMap = "network map"

	netMapV2 := resp.GetBody().NetMap()
	if netMapV2 == nil {
		return nil, newErrMissingResponseField(fieldNetMap)
	}

	err = res.netMap.ReadFromV2(*netMapV2)
	if err != nil {
		return nil, newErrInvalidResponseField(fieldNetMap, err)
	}

	return &res, nil
}