1. 1
2. 2
3. 3
4. 4
5. 5
6. 6
7. 7
8. 8
9. 9
10. 10
11. 11
12. 12
13. 13
14. 14
15. 15
16. 16
17. 17
18. 18
19. 19
20. 20
21. 21
22. 22
23. 23
24. 24
25. 25
26. 26
27. 27
28. 28
29. 29
30. 30
31. 31
32. 32
33. 33
34. 34
35. 35
36. 36
37. 37
38. 38
39. 39
40. 40
41. 41
42. 42
43. 43
44. 44
45. 45
46. 46
47. 47
48. 48
49. 49
50. 50
51. 51
52. 52
53. 53
54. 54
55. 55
56. 56
57. 57
58. 58
59. 59
60. 60
61. 61
62. 62
63. 63
64. 64
65. 65
66. 66
67. 67
68. 68
69. 69
70. 70
71. 71
72. 72
73. 73
74. 74
75. 75
76. 76
77. 77
78. 78
79. 79
80. 80
81. 81
82. 82
83. 83
84. 84
85. 85
86. 86
87. 87
88. 88
89. 89
90. 90
91. 91
92. 92
93. 93
94. 94
95. 95
96. 96
97. 97
98. 98
99. 99
100. 100
101. 101
102. 102
103. 103
104. 104
105. 105
106. 106
107. 107
108. 108
109. 109
110. 110
111. 111
112. 112
113. 113
114. 114
115. 115
116. 116
117. 117
118. 118
119. 119
120. 120
121. 121
122. 122
123. 123
124. 124
125. 125
126. 126
127. 127
128. 128
129. 129
130. 130
131. 131
132. 132
133. 133
134. 134
135. 135
136. 136
137. 137
138. 138
139. 139
140. 140
141. 141
142. 142
143. 143
144. 144
145. 145
146. 146
147. 147
148. 148
149. 149
150. 150
151. 151
152. 152
153. 153
154. 154
155. 155
156. 156
157. 157
158. 158
159. 159
160. 160
161. 161
162. 162
163. 163
164. 164
165. 165
166. 166

package qr

import (
	"image"
	"image/color"
	"math"

	"github.com/boombuler/barcode"
	"github.com/boombuler/barcode/utils"
)

type qrcode struct {
	dimension int
	data      *utils.BitList
	content   string
}

func (qr *qrcode) Content() string {
	return qr.content
}

func (qr *qrcode) Metadata() barcode.Metadata {
	return barcode.Metadata{barcode.TypeQR, 2}
}

func (qr *qrcode) ColorModel() color.Model {
	return color.Gray16Model
}

func (qr *qrcode) Bounds() image.Rectangle {
	return image.Rect(0, 0, qr.dimension, qr.dimension)
}

func (qr *qrcode) At(x, y int) color.Color {
	if qr.Get(x, y) {
		return color.Black
	}
	return color.White
}

func (qr *qrcode) Get(x, y int) bool {
	return qr.data.GetBit(x*qr.dimension + y)
}

func (qr *qrcode) Set(x, y int, val bool) {
	qr.data.SetBit(x*qr.dimension+y, val)
}

func (qr *qrcode) calcPenalty() uint {
	return qr.calcPenaltyRule1() + qr.calcPenaltyRule2() + qr.calcPenaltyRule3() + qr.calcPenaltyRule4()
}

func (qr *qrcode) calcPenaltyRule1() uint {
	var result uint
	for x := 0; x < qr.dimension; x++ {
		checkForX := false
		var cntX uint
		checkForY := false
		var cntY uint

		for y := 0; y < qr.dimension; y++ {
			if qr.Get(x, y) == checkForX {
				cntX++
			} else {
				checkForX = !checkForX
				if cntX >= 5 {
					result += cntX - 2
				}
				cntX = 1
			}

			if qr.Get(y, x) == checkForY {
				cntY++
			} else {
				checkForY = !checkForY
				if cntY >= 5 {
					result += cntY - 2
				}
				cntY = 1
			}
		}

		if cntX >= 5 {
			result += cntX - 2
		}
		if cntY >= 5 {
			result += cntY - 2
		}
	}

	return result
}

func (qr *qrcode) calcPenaltyRule2() uint {
	var result uint
	for x := 0; x < qr.dimension-1; x++ {
		for y := 0; y < qr.dimension-1; y++ {
			check := qr.Get(x, y)
			if qr.Get(x, y+1) == check && qr.Get(x+1, y) == check && qr.Get(x+1, y+1) == check {
				result += 3
			}
		}
	}
	return result
}

func (qr *qrcode) calcPenaltyRule3() uint {
	pattern1 := []bool{true, false, true, true, true, false, true, false, false, false, false}
	pattern2 := []bool{false, false, false, false, true, false, true, true, true, false, true}

	var result uint
	for x := 0; x <= qr.dimension-len(pattern1); x++ {
		for y := 0; y < qr.dimension; y++ {
			pattern1XFound := true
			pattern2XFound := true
			pattern1YFound := true
			pattern2YFound := true

			for i := 0; i < len(pattern1); i++ {
				iv := qr.Get(x+i, y)
				if iv != pattern1[i] {
					pattern1XFound = false
				}
				if iv != pattern2[i] {
					pattern2XFound = false
				}
				iv = qr.Get(y, x+i)
				if iv != pattern1[i] {
					pattern1YFound = false
				}
				if iv != pattern2[i] {
					pattern2YFound = false
				}
			}
			if pattern1XFound || pattern2XFound {
				result += 40
			}
			if pattern1YFound || pattern2YFound {
				result += 40
			}
		}
	}

	return result
}

func (qr *qrcode) calcPenaltyRule4() uint {
	totalNum := qr.data.Len()
	trueCnt := 0
	for i := 0; i < totalNum; i++ {
		if qr.data.GetBit(i) {
			trueCnt++
		}
	}
	percDark := float64(trueCnt) * 100 / float64(totalNum)
	floor := math.Abs(math.Floor(percDark/5) - 10)
	ceil := math.Abs(math.Ceil(percDark/5) - 10)
	return uint(math.Min(floor, ceil) * 10)
}

func newBarcode(dim int) *qrcode {
	res := new(qrcode)
	res.dimension = dim
	res.data = utils.NewBitList(dim * dim)
	return res
}