72 lines
2 KiB
Go
72 lines
2 KiB
Go
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// MIT License
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//
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// Copyright (c) 2020 Alex Howarth
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in all
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// copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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// SOFTWARE.
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package tilt
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import (
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"encoding/binary"
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"encoding/hex"
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"errors"
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)
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//iBeaconType identifies an iBeacon
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const iBeaconType uint32 = 0x4c000215
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// ErrNotBeacon - the BLE device is not an iBeacon
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var ErrNotBeacon = errors.New("not an iBeacon")
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// IBeacon data
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type IBeacon struct {
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UUID string
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Major uint16
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Minor uint16
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}
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// IsIBeacon to determine if data is an iBeacon
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func IsIBeacon(data []byte) bool {
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if len(data) < 25 {
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return false
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}
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if binary.BigEndian.Uint32(data) != iBeaconType {
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return false
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}
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return true
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}
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// NewIBeacon creates an iBeacon from a valid BLE event
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func NewIBeacon(data []byte) (b *IBeacon, err error) {
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if !IsIBeacon(data) {
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err = ErrNotBeacon
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return
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}
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b = &IBeacon{
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UUID: hex.EncodeToString(data[4:20]),
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Major: binary.BigEndian.Uint16(data[20:22]),
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Minor: binary.BigEndian.Uint16(data[22:24]),
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}
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return
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}
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