// Copyright (c) Mainflux
// SPDX-License-Identifier: Apache-2.0

package sdk

import (
	"encoding/json"
	"fmt"
	"net/http"
	"strings"

	"github.com/mainflux/mainflux/pkg/errors"
)

const (
	thingsEndpoint   = "things"
	connectEndpoint  = "connect"
	identifyEndpoint = "identify"
)

type identifyThingReq struct {
	Token string `json:"token,omitempty"`
}

type identifyThingResp struct {
	ID string `json:"id,omitempty"`
}

func (sdk mfSDK) CreateThing(t Thing, token string) (string, errors.SDKError) {
	data, err := json.Marshal(t)
	if err != nil {
		return "", errors.NewSDKError(err)
	}
	url := fmt.Sprintf("%s/%s", sdk.thingsURL, thingsEndpoint)

	headers, _, sdkerr := sdk.processRequest(http.MethodPost, url, token, string(CTJSON), data, http.StatusCreated)
	if sdkerr != nil {
		return "", sdkerr
	}

	id := strings.TrimPrefix(headers.Get("Location"), fmt.Sprintf("/%s/", thingsEndpoint))
	return id, nil
}

func (sdk mfSDK) CreateThings(things []Thing, token string) ([]Thing, errors.SDKError) {
	data, err := json.Marshal(things)
	if err != nil {
		return []Thing{}, errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s", sdk.thingsURL, thingsEndpoint, "bulk")

	_, body, sdkerr := sdk.processRequest(http.MethodPost, url, token, string(CTJSON), data, http.StatusCreated)
	if sdkerr != nil {
		return []Thing{}, sdkerr
	}

	var ctr createThingsRes
	if err := json.Unmarshal(body, &ctr); err != nil {
		return []Thing{}, errors.NewSDKError(err)
	}

	return ctr.Things, nil
}

func (sdk mfSDK) Things(pm PageMetadata, token string) (ThingsPage, errors.SDKError) {
	url, err := sdk.withQueryParams(sdk.thingsURL, thingsEndpoint, pm)
	if err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}

	_, body, sdkerr := sdk.processRequest(http.MethodGet, url, token, string(CTJSON), nil, http.StatusOK)
	if sdkerr != nil {
		return ThingsPage{}, sdkerr
	}

	var tp ThingsPage
	if err := json.Unmarshal(body, &tp); err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}

	return tp, nil
}

func (sdk mfSDK) ThingsByChannel(chanID string, pm PageMetadata, token string) (ThingsPage, errors.SDKError) {
	url, err := sdk.withQueryParams(fmt.Sprintf("%s/channels/%s", sdk.thingsURL, chanID), thingsEndpoint, pm)
	if err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}
	_, body, sdkerr := sdk.processRequest(http.MethodGet, url, token, string(CTJSON), nil, http.StatusOK)
	if sdkerr != nil {
		return ThingsPage{}, sdkerr
	}

	var tp ThingsPage
	if err := json.Unmarshal(body, &tp); err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}

	return tp, nil
}

func (sdk mfSDK) Thing(id, token string) (Thing, errors.SDKError) {
	url := fmt.Sprintf("%s/%s/%s", sdk.thingsURL, thingsEndpoint, id)

	_, body, err := sdk.processRequest(http.MethodGet, url, token, string(CTJSON), nil, http.StatusOK)
	if err != nil {
		return Thing{}, err
	}

	var t Thing
	if err := json.Unmarshal(body, &t); err != nil {
		return Thing{}, errors.NewSDKError(err)
	}

	return t, nil
}

func (sdk mfSDK) UpdateThing(t Thing, token string) errors.SDKError {
	data, err := json.Marshal(t)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s", sdk.thingsURL, thingsEndpoint, t.ID)

	_, _, sdkerr := sdk.processRequest(http.MethodPut, url, token, string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) DeleteThing(id, token string) errors.SDKError {
	url := fmt.Sprintf("%s/%s/%s", sdk.thingsURL, thingsEndpoint, id)

	_, _, err := sdk.processRequest(http.MethodDelete, url, token, string(CTJSON), nil, http.StatusNoContent)
	return err
}

func (sdk mfSDK) ShareThing(thingID, userID string, policies []string, token string) errors.SDKError {
	sReq := shareThingReq{
		UserID:   userID,
		Policies: policies,
	}
	data, err := json.Marshal(sReq)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s/share", sdk.thingsURL, thingsEndpoint, thingID)

	_, _, sdkerr := sdk.processRequest(http.MethodPost, url, token, string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) UpdateThingKey(id, key, token string) errors.SDKError {
	req := map[string]string{
		"key": key,
	}
	data, err := json.Marshal(req)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s/key", sdk.thingsURL, thingsEndpoint, id)

	_, _, sdkerr := sdk.processRequest(http.MethodPatch, url, token, string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) IdentifyThing(key string) (string, errors.SDKError) {
	idReq := identifyThingReq{Token: key}
	data, err := json.Marshal(idReq)
	if err != nil {
		return "", errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s", sdk.thingsURL, identifyEndpoint)

	_, body, sdkerr := sdk.processRequest(http.MethodPost, url, "", string(CTJSON), data, http.StatusOK)
	if sdkerr != nil {
		return "", sdkerr
	}

	var i identifyThingResp
	if err := json.Unmarshal(body, &i); err != nil {
		return "", errors.NewSDKError(err)
	}

	return i.ID, nil
}

func (sdk mfSDK) AccessByThingKey(channelID, key string) (string, errors.SDKError) {
	idReq := identifyThingReq{Token: key}
	data, err := json.Marshal(idReq)
	if err != nil {
		return "", errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s/%s/access-by-key", sdk.thingsURL, identifyEndpoint, channelsEndpoint, channelID)

	_, body, sdkerr := sdk.processRequest(http.MethodPost, url, "", string(CTJSON), data, http.StatusOK)
	if sdkerr != nil {
		return "", sdkerr
	}

	var i identifyThingResp
	if err := json.Unmarshal(body, &i); err != nil {
		return "", errors.NewSDKError(err)
	}

	return i.ID, nil
}

func (sdk mfSDK) AccessByThingID(channelID, id string) errors.SDKError {
	req := map[string]string{
		"thing_id": id,
	}
	data, err := json.Marshal(req)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s/%s/%s/access-by-id", sdk.thingsURL, identifyEndpoint, channelsEndpoint, channelID)

	_, _, sdkerr := sdk.processRequest(http.MethodPost, url, "", string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) Connect(connIDs ConnectionIDs, token string) errors.SDKError {
	data, err := json.Marshal(connIDs)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s", sdk.thingsURL, connectEndpoint)

	_, _, sdkerr := sdk.processRequest(http.MethodPost, url, token, string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) Disconnect(connIDs ConnectionIDs, token string) errors.SDKError {
	data, err := json.Marshal(connIDs)
	if err != nil {
		return errors.NewSDKError(err)
	}

	url := fmt.Sprintf("%s/%s", sdk.thingsURL, connectEndpoint)

	_, _, sdkerr := sdk.processRequest(http.MethodPut, url, token, string(CTJSON), data, http.StatusOK)
	return sdkerr
}

func (sdk mfSDK) ConnectThing(thingID, chanID, token string) errors.SDKError {
	url := fmt.Sprintf("%s/%s/%s/%s/%s", sdk.thingsURL, channelsEndpoint, chanID, thingsEndpoint, thingID)

	_, _, err := sdk.processRequest(http.MethodPut, url, token, string(CTJSON), nil, http.StatusOK)
	return err
}

func (sdk mfSDK) DisconnectThing(thingID, chanID, token string) errors.SDKError {
	url := fmt.Sprintf("%s/%s/%s/%s/%s", sdk.thingsURL, channelsEndpoint, chanID, thingsEndpoint, thingID)

	_, _, err := sdk.processRequest(http.MethodDelete, url, token, string(CTJSON), nil, http.StatusNoContent)
	return err
}

func (sdk mfSDK) SearchThing(t Thing, pm PageMetadata, token string) (ThingsPage, errors.SDKError) {
	sReq := searchThingReq{
		Thing: t, Total: pm.Total, Offset: pm.Offset, Limit: pm.Limit,
	}
	data, err := json.Marshal(sReq)
	if err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}
	url := fmt.Sprintf("%s/%s/search", sdk.thingsURL, thingsEndpoint)

	_, body, sdkerr := sdk.processRequest(http.MethodPost, url, token, string(CTJSON), data, http.StatusOK)
	if sdkerr != nil {
		return ThingsPage{}, sdkerr
	}

	var tp ThingsPage
	if err := json.Unmarshal(body, &tp); err != nil {
		return ThingsPage{}, errors.NewSDKError(err)
	}

	return tp, nil
}

type searchThingReq struct {
	Total  uint64 `json:"total,omitempty"`
	Offset uint64 `json:"offset,omitempty"`
	Limit  uint64 `json:"limit,omitempty"`
	Order  string `json:"order,omitempty"`
	Dir    string `json:"dir,omitempty"`
	Thing
}

type shareThingReq struct {
	UserID   string   `json:"user_id,omitempty"`
	Policies []string `json:"policies,omitempty"`
}