lockserver/httpserver/codes.go

package httpserver

import (
	"database/sql"
	"errors"
	"fmt"
	"math/rand"
	"strings"

	"git.janky.solutions/finn/lockserver/config"
	"git.janky.solutions/finn/lockserver/db"
	"git.janky.solutions/finn/lockserver/zwavejs"
	"github.com/labstack/echo/v4"
	"github.com/sirupsen/logrus"
)

func addCode(c echo.Context) error {
	// name := c.FormValue("name")
	code := c.FormValue("code")

	queries, dbc, err := db.Get()
	if err != nil {
		return err
	}
	defer dbc.Close()

	ctx := c.Request().Context()

	// generate a code that isn't used on any lock or if the user
	// supplied a code, check if it's already used on any lock and
	// error out if it is
	noCodeSupplied := code == "" // if no code is supplied, we must generate one
	for {
		if noCodeSupplied {
			code = generateCode()
			logrus.WithField("code", code).Debug("generated code")
		}

		row, err := queries.GetLockCodesByCode(ctx, code)
		if err != nil {
			return fmt.Errorf("error checking if code was already in use: %v", err)
		}

		if len(row) == 0 {
			break
		}

		if noCodeSupplied {
			continue
		}

		return fmt.Errorf("requested code (%s) is already in use on some or all locks", code)
	}

	locks, err := queries.GetLocks(ctx)
	if err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return errors.New("no locks currently registered, cannot add code")
		}
		return fmt.Errorf("error getting locks: %v", err)
	}

	client := c.Get(contextKeyZWaveClient).(*zwavejs.Client)
	for _, lock := range locks {
		slot, err := queries.GetEmptySlot(ctx, lock.ID)
		if err != nil {
			if errors.Is(err, sql.ErrNoRows) {
				return fmt.Errorf("no empty code slots found on lock %s (ZWaveDeviceID=%d ID=%d)", lock.Name, lock.ZwaveDeviceID, lock.ID)
			}
			return fmt.Errorf("error looking for empty code slot on lock %s (ZWaveDeviceID=%d ID=%d): %v", lock.Name, lock.ZwaveDeviceID, lock.ID, err)
		}

		// send the code to the lock
		// sample from https://github.com/FutureTense/keymaster/blob/f4f1046bddb7901cbd3ce7820886be1ff7895fe7/tests/test_services.py#L88
		//
		//	{
		//		"ccVersion": 1,
		//		"commandClassName": "User Code",
		//		"commandClass": 99,
		//		"endpoint": 0,
		//		"property": "userCode",
		//		"propertyName": "userCode",
		//		"propertyKey": 1,
		//		"propertyKeyName": "1",
		//		"metadata": {
		//			"type": "string",
		//			"readable": True,
		//			"writeable": True,
		//			"minLength": 4,
		//			"maxLength": 10,
		//			"label": "User Code (1)",
		//		},
		//		"value": "123456",
		//	}
		err = client.SetNodeValue(ctx, int(lock.ZwaveDeviceID), zwavejs.NodeValue{
			CCVersion:        1,
			CommandClassName: zwavejs.CommandClassNameUserCode,
			CommandClass:     zwavejs.CommandClassUserCode,
			Endpoint:         0,
			Property:         zwavejs.AnyType{Type: zwavejs.AnyTypeString, String: string(zwavejs.PropertyUserCode)},
			PropertyName:     zwavejs.AnyType{Type: zwavejs.AnyTypeString, String: string(zwavejs.PropertyUserCode)},
			PropertyKey:      zwavejs.AnyType{Type: zwavejs.AnyTypeInt, Int: int(slot.ID)},
		}, zwavejs.AnyType{Type: zwavejs.AnyTypeString, String: code})
		if err != nil {
			return fmt.Errorf("error pushing code to lock %s (ZWaveDeviceID=%d ID=%d): %v", lock.Name, lock.ZwaveDeviceID, lock.ID, err)
		}

		// set the code on the lock
		// set the code in the db
	}
	// add row to user_codes
	// add row to user_code_slots
	// redirect to /user-codes/<code id>

	return errors.New("not yet implemented")
}

var codeCharSet = "0123456789"

func generateCode() string {
	var builder strings.Builder
	for i := 0; i < config.C.GeneratedCodeLength; i++ {
		builder.WriteByte(codeCharSet[rand.Int31n(int32(len(codeCharSet)))])
	}
	return builder.String()
}