class code128b {
	// 输入数据
	data = ""

	// Code 128 模式表：索引0..106 -> 二进制模块串（1=黑，0=白），来自业界通用表
	// 参考：StartB=104 -> 11010010000, Stop=106 -> 1100011101011
	private static PATTERNS = [
		"11011001100","11001101100","11001100110","10010011000","10010001100","10001001100",
		"10011001000","10011000100","10001100100","11001001000","11001000100","11000100100",
		"10110011100","10011011100","10011001110","10111001100","10011101100","10011100110",
		"11001110010","11001011100","11001001110","11011100100","11001110100","11101101110",
		"11101001100","11100101100","11100100110","11101100100","11100110100","11100110010",
		"11011011000","11011000110","11000110110","10100011000","10001011000","10001000110",
		"10110001000","10001101000","10001100010","11010001000","11000101000","11000100010",
		"10110111000","10110001110","10001101110","10111011000","10111000110","10001110110",
		"11101110110","11010001110","11000101110","11011101000","11011100010","11011101110",
		"11101011000","11101000110","11100010110","11101101000","11101100010","11100011010",
		"11101111010","11001000010","11110001010","10100110000","10100001100","10010110000",
		"10010000110","10000101100","10000100110","10110010000","10110000100","10011010000",
		"10011000010","10000110100","10000110010","11000010010","11001010000","11110111010",
		"11000010100","10001111010","10100111100","10010111100","10010011110","10111100100",
		"10011110100","10011110010","11110100100","11110010100","11110010010","11011011110",
		"11011110110","11110110110","10101111000","10100011110","10001011110","10111101000",
		"10111100010","11110101000","11110100010","10111011110","10111101110","11101011110",
		"11110101110","11010000100","11010010000","11010011100","1100011101011"
	]

	// Code Set B: 字符到值（0..95 => ASCII 32..127）
	private mapCharToValueB(ch:string):number {
		const code = ch.charCodeAt(0)!;
		
		if (code < 32 || code > 127) {
			return -1
		}
		return code - 32
	}

	constructor(text:string) {
		this.data = text
	}

	encode():string {
		if (this.data.length == 0) return ""
		const values = [] as number[]
		for (let i = 0; i < this.data.length; i++) {
			values.push(this.mapCharToValueB(this.data.charAt(i)))
		}
		// 起始码 CodeB=104
		const startVal = 104
		let checksum = startVal
		for (let i = 0; i < values.length; i++) {
			checksum += values[i] * (i + 1)
		}
		checksum = checksum % 103
		// 组合：StartB + 数据 + 校验 + Stop
		const bits = [] as string[]
		bits.push(code128b.PATTERNS[startVal])
		for (let i = 0; i < values.length; i++) {
			bits.push(code128b.PATTERNS[values[i]])
		}
		bits.push(code128b.PATTERNS[checksum])
		// Stop=106
		bits.push(code128b.PATTERNS[106])
		return bits.join("")
	}
}

export { code128b };