ENCODING!! and lots of organization

decoders/info/index.js

@@ -0,0 +1,7 @@
+const SystemNameChunk = require('./info-system-name-chunk');
+const TrackerListChunk = require('./info-tracker-list-chunk');
+
+module.exports = {
+  SystemNameChunk,
+  TrackerListChunk,
+};

decoders/info/info-system-name-chunk.js

@@ -0,0 +1,3 @@
+const Parser = require('binary-parser').Parser;
+
+module.exports = new Parser().string('system_name', { greedy: true });

decoders/info/info-tracker-list-chunk.js

@@ -0,0 +1,39 @@
+const Parser = require('binary-parser').Parser;
+
+const infoTrackerNameParser = new Parser()
+  .uint16le('id')
+  .uint16le('data_len', {
+    formatter: (item) => {
+      const binary = item.toString(2).padStart(16, '0');
+      return Number.parseInt(binary.substring(1), 2);
+    },
+  })
+  .seek(-2)
+  .uint16le('has_subchunks', {
+    formatter: (item) => {
+      const binary = item.toString(2).padStart(16, '0');
+      return binary.charAt(0) === '1';
+    },
+  })
+  .string('tracker_name', { length: 'data_len' });
+
+const infoTrackerParser = new Parser()
+  .uint16le('id')
+  .uint16le('data_len', {
+    formatter: (item) => {
+      const binary = item.toString(2).padStart(16, '0');
+      return Number.parseInt(binary.substring(1), 2);
+    },
+  })
+  .seek(-2)
+  .uint16le('has_subchunks', {
+    formatter: (item) => {
+      const binary = item.toString(2).padStart(16, '0');
+      return binary.charAt(0) === '1';
+    },
+  })
+  .nest('tracker_name', {
+    type: infoTrackerNameParser,
+  });
+
+module.exports = new Parser().array('trackers', { type: infoTrackerParser, readUntil: 'eof' });