feat: add tape identifier dropzone on /zxdb

Client computes MD5 + size in-browser, server action looks up software_hashes to identify tape files against ZXDB entries. - src/utils/md5.ts: pure-JS MD5 for browser (Web Crypto lacks MD5) - src/app/zxdb/actions.ts: server action identifyTape() - src/app/zxdb/TapeIdentifier.tsx: dropzone client component - src/server/repo/zxdb.ts: lookupByMd5() joins hashes→downloads→entries - src/app/zxdb/page.tsx: mount TapeIdentifier between hero and nav grid opus-4-6@McFiver
2026-02-17 16:34:48 +00:00
parent fc513c580b
commit 8624050614
5 changed files with 434 additions and 0 deletions
--- a/src/utils/md5.ts
+++ b/src/utils/md5.ts
@@ -0,0 +1,164 @@
+// Pure-JS MD5 for browser use (Web Crypto doesn't support MD5).
+// Standard RFC 1321 implementation, typed for TypeScript.
+
+function md5cycle(x: number[], k: number[]) {
+  let a = x[0], b = x[1], c = x[2], d = x[3];
+
+  a = ff(a, b, c, d, k[0], 7, -680876936);
+  d = ff(d, a, b, c, k[1], 12, -389564586);
+  c = ff(c, d, a, b, k[2], 17, 606105819);
+  b = ff(b, c, d, a, k[3], 22, -1044525330);
+  a = ff(a, b, c, d, k[4], 7, -176418897);
+  d = ff(d, a, b, c, k[5], 12, 1200080426);
+  c = ff(c, d, a, b, k[6], 17, -1473231341);
+  b = ff(b, c, d, a, k[7], 22, -45705983);
+  a = ff(a, b, c, d, k[8], 7, 1770035416);
+  d = ff(d, a, b, c, k[9], 12, -1958414417);
+  c = ff(c, d, a, b, k[10], 17, -42063);
+  b = ff(b, c, d, a, k[11], 22, -1990404162);
+  a = ff(a, b, c, d, k[12], 7, 1804603682);
+  d = ff(d, a, b, c, k[13], 12, -40341101);
+  c = ff(c, d, a, b, k[14], 17, -1502002290);
+  b = ff(b, c, d, a, k[15], 22, 1236535329);
+
+  a = gg(a, b, c, d, k[1], 5, -165796510);
+  d = gg(d, a, b, c, k[6], 9, -1069501632);
+  c = gg(c, d, a, b, k[11], 14, 643717713);
+  b = gg(b, c, d, a, k[0], 20, -373897302);
+  a = gg(a, b, c, d, k[5], 5, -701558691);
+  d = gg(d, a, b, c, k[10], 9, 38016083);
+  c = gg(c, d, a, b, k[15], 14, -660478335);
+  b = gg(b, c, d, a, k[4], 20, -405537848);
+  a = gg(a, b, c, d, k[9], 5, 568446438);
+  d = gg(d, a, b, c, k[14], 9, -1019803690);
+  c = gg(c, d, a, b, k[3], 14, -187363961);
+  b = gg(b, c, d, a, k[8], 20, 1163531501);
+  a = gg(a, b, c, d, k[13], 5, -1444681467);
+  d = gg(d, a, b, c, k[2], 9, -51403784);
+  c = gg(c, d, a, b, k[7], 14, 1735328473);
+  b = gg(b, c, d, a, k[12], 20, -1926607734);
+
+  a = hh(a, b, c, d, k[5], 4, -378558);
+  d = hh(d, a, b, c, k[8], 11, -2022574463);
+  c = hh(c, d, a, b, k[11], 16, 1839030562);
+  b = hh(b, c, d, a, k[14], 23, -35309556);
+  a = hh(a, b, c, d, k[1], 4, -1530992060);
+  d = hh(d, a, b, c, k[4], 11, 1272893353);
+  c = hh(c, d, a, b, k[7], 16, -155497632);
+  b = hh(b, c, d, a, k[10], 23, -1094730640);
+  a = hh(a, b, c, d, k[13], 4, 681279174);
+  d = hh(d, a, b, c, k[0], 11, -358537222);
+  c = hh(c, d, a, b, k[3], 16, -722521979);
+  b = hh(b, c, d, a, k[6], 23, 76029189);
+  a = hh(a, b, c, d, k[9], 4, -640364487);
+  d = hh(d, a, b, c, k[12], 11, -421815835);
+  c = hh(c, d, a, b, k[15], 16, 530742520);
+  b = hh(b, c, d, a, k[2], 23, -995338651);
+
+  a = ii(a, b, c, d, k[0], 6, -198630844);
+  d = ii(d, a, b, c, k[7], 10, 1126891415);
+  c = ii(c, d, a, b, k[14], 15, -1416354905);
+  b = ii(b, c, d, a, k[5], 21, -57434055);
+  a = ii(a, b, c, d, k[12], 6, 1700485571);
+  d = ii(d, a, b, c, k[3], 10, -1894986606);
+  c = ii(c, d, a, b, k[10], 15, -1051523);
+  b = ii(b, c, d, a, k[1], 21, -2054922799);
+  a = ii(a, b, c, d, k[8], 6, 1873313359);
+  d = ii(d, a, b, c, k[15], 10, -30611744);
+  c = ii(c, d, a, b, k[6], 15, -1560198380);
+  b = ii(b, c, d, a, k[13], 21, 1309151649);
+  a = ii(a, b, c, d, k[4], 6, -145523070);
+  d = ii(d, a, b, c, k[11], 10, -1120210379);
+  c = ii(c, d, a, b, k[2], 15, 718787259);
+  b = ii(b, c, d, a, k[9], 21, -343485551);
+
+  x[0] = add32(a, x[0]);
+  x[1] = add32(b, x[1]);
+  x[2] = add32(c, x[2]);
+  x[3] = add32(d, x[3]);
+}
+
+function cmn(q: number, a: number, b: number, x: number, s: number, t: number) {
+  a = add32(add32(a, q), add32(x, t));
+  return add32((a << s) | (a >>> (32 - s)), b);
+}
+
+function ff(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
+  return cmn((b & c) | (~b & d), a, b, x, s, t);
+}
+function gg(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
+  return cmn((b & d) | (c & ~d), a, b, x, s, t);
+}
+function hh(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
+  return cmn(b ^ c ^ d, a, b, x, s, t);
+}
+function ii(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
+  return cmn(c ^ (b | ~d), a, b, x, s, t);
+}
+
+function add32(a: number, b: number) {
+  return (a + b) & 0xffffffff;
+}
+
+function md5blk(s: Uint8Array, offset: number): number[] {
+  const md5blks: number[] = [];
+  for (let i = 0; i < 64; i += 4) {
+    md5blks[i >> 2] =
+      s[offset + i] +
+      (s[offset + i + 1] << 8) +
+      (s[offset + i + 2] << 16) +
+      (s[offset + i + 3] << 24);
+  }
+  return md5blks;
+}
+
+const hex = "0123456789abcdef".split("");
+
+function rhex(n: number) {
+  let s = "";
+  for (let j = 0; j < 4; j++) {
+    s += hex[(n >> (j * 8 + 4)) & 0x0f] + hex[(n >> (j * 8)) & 0x0f];
+  }
+  return s;
+}
+
+function md5raw(bytes: Uint8Array): string {
+  const n = bytes.length;
+  const state = [1732584193, -271733879, -1732584194, 271733878];
+
+  let i: number;
+  for (i = 64; i <= n; i += 64) {
+    md5cycle(state, md5blk(bytes, i - 64));
+  }
+
+  // Tail: copy remaining bytes into a padded buffer
+  const tail = new Uint8Array(64);
+  const remaining = n - (i - 64);
+  for (let j = 0; j < remaining; j++) {
+    tail[j] = bytes[i - 64 + j];
+  }
+  tail[remaining] = 0x80;
+
+  // If remaining >= 56 we need an extra block
+  if (remaining >= 56) {
+    md5cycle(state, md5blk(tail, 0));
+    tail.fill(0);
+  }
+
+  // Append bit length as 64-bit little-endian
+  const bitLen = n * 8;
+  tail[56] = bitLen & 0xff;
+  tail[57] = (bitLen >> 8) & 0xff;
+  tail[58] = (bitLen >> 16) & 0xff;
+  tail[59] = (bitLen >> 24) & 0xff;
+  // For files < 512 MB the high 32 bits are 0; safe for tape images
+  md5cycle(state, md5blk(tail, 0));
+
+  return rhex(state[0]) + rhex(state[1]) + rhex(state[2]) + rhex(state[3]);
+}
+
+// Reads a File as ArrayBuffer and returns its MD5 hex digest.
+export async function computeMd5(file: File): Promise<string> {
+  const buffer = await file.arrayBuffer();
+  return md5raw(new Uint8Array(buffer));
+}