refactor(sdk): musicSdk 全量迁移至 TypeScript

musicSdk/mg/utils/mrc.ts

@@ -0,0 +1,104 @@
+
+// const key = 'karakal@123Qcomyidongtiantianhaoting'
+const DELTA = 2654435769n
+const MIN_LENGTH = 32
+// const SPECIAL_CHAR = '0'
+const keyArr = [
+  27303562373562475n,
+  18014862372307051n,
+  22799692160172081n,
+  34058940340699235n,
+  30962724186095721n,
+  27303523720101991n,
+  27303523720101998n,
+  31244139033526382n,
+  28992395054481524n,
+]
+
+
+const teaDecrypt = (data: bigint[], key: bigint[]): bigint[] => {
+  const length = data.length
+  const lengthBitint = BigInt(length)
+  if (length >= 1) {
+    // let j = data[data.length - 1];
+    let j2 = data[0]
+    let j3 = toLong((6n + (52n / lengthBitint)) * DELTA)
+    while (true) {
+      let j4 = j3
+      if (j4 == 0n) break
+      let j5 = toLong(3n & toLong(j4 >> 2n))
+      let j6 = lengthBitint
+      while (true) {
+        j6--
+        if (j6 > 0n) {
+          let j7 = data[(j6 - 1n) as unknown as number]
+          let i = j6 as unknown as number
+          j2 = toLong(data[i] - (toLong(toLong(j2 ^ j4) + toLong(j7 ^ key[toLong(toLong(3n & j6) ^ j5) as unknown as number])) ^ toLong(toLong(toLong(j7 >> 5n) ^ toLong(j2 << 2n)) + toLong(toLong(j2 >> 3n) ^ toLong(j7 << 4n)))))
+          data[i] = j2
+        } else break
+      }
+      let j8 = data[lengthBitint - 1n as unknown as number]
+      j2 = toLong(data[0n as unknown as number] - toLong(toLong(toLong(key[toLong(toLong(j6 & 3n) ^ j5) as unknown as number] ^ j8) + toLong(j2 ^ j4)) ^ toLong(toLong(toLong(j8 >> 5n) ^ toLong(j2 << 2n)) + toLong(toLong(j2 >> 3n) ^ toLong(j8 << 4n)))))
+      data[0] = j2
+      j3 = toLong(j4 - DELTA)
+    }
+  }
+  return data
+}
+
+const longArrToString = (data: bigint[]): string => {
+  const arrayList: string[] = []
+  for (const j of data) arrayList.push(longToBytes(j).toString('utf16le'))
+  return arrayList.join('')
+}
+
+// https://stackoverflow.com/a/29132118
+const longToBytes = (l: bigint): Buffer => {
+  const result = Buffer.alloc(8)
+  for (let i = 0; i < 8; i++) {
+    result[i] = parseInt((l & 0xFFn) as unknown as string)
+    l >>= 8n
+  }
+  return result
+}
+
+
+const toBigintArray = (data: string): bigint[] => {
+  const length = Math.floor(data.length / 16)
+  const jArr: bigint[] = Array(length)
+  for (let i = 0; i < length; i++) {
+    jArr[i] = toLong(data.substring(i * 16, (i * 16) + 16))
+  }
+  return jArr
+}
+
+// https://github.com/lyswhut/lx-music-desktop/issues/445#issuecomment-1139338682
+const MAX = 9223372036854775807n
+const MIN = -9223372036854775808n
+const toLong = (str: string | bigint): bigint => {
+  const num = typeof str == 'string' ? BigInt('0x' + str) : str
+  if (num > MAX) return toLong(num - (1n << 64n))
+  else if (num < MIN) return toLong(num + (1n << 64n))
+  return num
+}
+
+export const decrypt = (data: string | null): string | null => {
+  // console.log(data.length)
+  // -3551594764563790630
+  // console.log(toLongArrayFromArr(Buffer.from(key)))
+  // console.log(teaDecrypt(toBigintArray(data), keyArr))
+  // console.log(longArrToString(teaDecrypt(toBigintArray(data), keyArr)))
+  // console.log(toByteArray(teaDecrypt(toBigintArray(data), keyArr)))
+  return (data == null || data.length < MIN_LENGTH)
+    ? data
+    : longArrToString(teaDecrypt(toBigintArray(data), keyArr))
+}
+
+// console.log(14895149309145760986n - )
+// console.log(toLong('14895149309145760986'))
+// console.log(decrypt(str))
+// console.log(decrypt(str))
+// console.log(toByteArray([6048138644744000495n]))
+// console.log(toByteArray([16325999628386395n]))
+// console.log(toLong(90994076459972177136n))
+