feat: add Shoutcast v1 stream support via raw socket fallback

Shoutcast v1 servers respond with `ICY 200 OK` instead of valid HTTP,
which OkHttp rejects. StreamConnection now falls back to a raw socket
that manually parses ICY headers when OkHttp fails with a protocol error.
No downstream changes needed — IcyParser and the audio pipeline already
handle the identical ICY metadata format.

Made-with: Cursor

app/src/main/java/xyz/cottongin/radio247/audio/StreamConnection.kt

@@ -1,11 +1,15 @@
 package xyz.cottongin.radio247.audio
 
+import android.util.Log
 import okhttp3.OkHttpClient
 import okhttp3.Protocol
 import okhttp3.Request
 import okhttp3.Response
+import java.io.BufferedInputStream
 import java.io.IOException
 import java.io.InputStream
+import java.net.Socket
+import java.net.URL
 import java.time.Duration
 
 class ConnectionFailed(message: String, cause: Throwable? = null) : Exception(message, cause)
@@ -31,31 +35,81 @@ class StreamConnection(private val url: String) {
     var streamInfo: StreamInfo? = null
         private set
     private var response: Response? = null
+    private var rawSocket: Socket? = null
 
     fun open() {
+        try {
+            openWithOkHttp()
+        } catch (e: IOException) {
+            if (looksLikeIcyProtocolError(e)) {
+                Log.i(TAG, "OkHttp rejected response (likely ICY protocol), falling back to raw socket")
+                openWithRawSocket()
+            } else {
+                throw ConnectionFailed("Network error", e)
+            }
+        }
+    }
+
+    private fun openWithOkHttp() {
         val request = Request.Builder()
             .url(url)
             .header("Icy-MetaData", "1")
             .header("User-Agent", "Radio247/1.0")
             .build()
 
+        val resp = client.newCall(request).execute()
+        if (!resp.isSuccessful) {
+            resp.close()
+            throw ConnectionFailed("HTTP ${resp.code}")
+        }
+        response = resp
+        metaint = resp.header("icy-metaint")?.toIntOrNull()
+        streamInfo = StreamInfo(
+            bitrate = resp.header("icy-br")?.toIntOrNull(),
+            ssl = url.startsWith("https", ignoreCase = true),
+            contentType = resp.header("Content-Type")
+        )
+        inputStream = resp.body?.byteStream()
+            ?: throw ConnectionFailed("Empty response body")
+    }
+
+    private fun openWithRawSocket() {
         try {
-            val resp = client.newCall(request).execute()
-            if (!resp.isSuccessful) {
-                resp.close()
-                throw ConnectionFailed("HTTP ${resp.code}")
-            }
-            response = resp
-            metaint = resp.header("icy-metaint")?.toIntOrNull()
+            val parsed = URL(url)
+            val host = parsed.host ?: throw ConnectionFailed("No host in URL")
+            val port = if (parsed.port != -1) parsed.port else parsed.defaultPort
+            val path = if (parsed.path.isNullOrEmpty()) "/" else parsed.path
+
+            val socket = Socket(host, port)
+            socket.soTimeout = 30_000
+            rawSocket = socket
+
+            val out = socket.getOutputStream()
+            val requestStr = "GET $path HTTP/1.0\r\n" +
+                "Host: $host\r\n" +
+                "User-Agent: Radio247/1.0\r\n" +
+                "Icy-MetaData: 1\r\n" +
+                "Accept: */*\r\n" +
+                "\r\n"
+            out.write(requestStr.toByteArray(Charsets.US_ASCII))
+            out.flush()
+
+            val buffered = BufferedInputStream(socket.getInputStream(), 16384)
+            val headers = parseIcyHeaders(buffered)
+
+            metaint = headers["icy-metaint"]?.toIntOrNull()
             streamInfo = StreamInfo(
-                bitrate = resp.header("icy-br")?.toIntOrNull(),
+                bitrate = headers["icy-br"]?.toIntOrNull(),
                 ssl = url.startsWith("https", ignoreCase = true),
-                contentType = resp.header("Content-Type")
+                contentType = headers["content-type"]
             )
-            inputStream = resp.body?.byteStream()
-                ?: throw ConnectionFailed("Empty response body")
+            inputStream = buffered
+        } catch (e: ConnectionFailed) {
+            closeRawSocket()
+            throw e
         } catch (e: IOException) {
-            throw ConnectionFailed("Network error", e)
+            closeRawSocket()
+            throw ConnectionFailed("Network error (raw socket)", e)
         }
     }
 
@@ -66,9 +120,74 @@ class StreamConnection(private val url: String) {
         try {
             response?.close()
         } catch (_: IOException) {}
+        closeRawSocket()
         response = null
         inputStream = null
         metaint = null
         streamInfo = null
     }
+
+    private fun closeRawSocket() {
+        try {
+            rawSocket?.close()
+        } catch (_: IOException) {}
+        rawSocket = null
+    }
+
+    companion object {
+        private const val TAG = "StreamConnection"
+
+        /**
+         * Shoutcast v1 servers respond with `ICY 200 OK` instead of a valid HTTP
+         * status line. OkHttp surfaces this as a ProtocolException.
+         */
+        internal fun looksLikeIcyProtocolError(e: IOException): Boolean {
+            val msg = e.message ?: return false
+            return msg.contains("unexpected status line", ignoreCase = true) ||
+                msg.contains("http/0.9", ignoreCase = true) ||
+                e.javaClass.simpleName == "ProtocolException"
+        }
+
+        /**
+         * Reads headers line-by-line from an ICY response until the blank line.
+         * Returns a map of lowercased header names to values. Throws
+         * [ConnectionFailed] if the status line is not `ICY 200 OK` or `HTTP/1.x 200`.
+         */
+        internal fun parseIcyHeaders(input: InputStream): Map<String, String> {
+            val statusLine = readLine(input)
+            if (!statusLine.startsWith("ICY ", ignoreCase = true) &&
+                !statusLine.startsWith("HTTP/", ignoreCase = true)
+            ) {
+                throw ConnectionFailed("Unexpected status line: $statusLine")
+            }
+
+            val headers = mutableMapOf<String, String>()
+            while (true) {
+                val line = readLine(input)
+                if (line.isEmpty()) break
+                val colon = line.indexOf(':')
+                if (colon > 0) {
+                    headers[line.substring(0, colon).trim().lowercase()] =
+                        line.substring(colon + 1).trim()
+                }
+            }
+            return headers
+        }
+
+        private fun readLine(input: InputStream): String {
+            val sb = StringBuilder(128)
+            while (true) {
+                val b = input.read()
+                if (b == -1) break
+                if (b == '\n'.code) break
+                if (b == '\r'.code) {
+                    input.mark(1)
+                    if (input.read() != '\n'.code) input.reset()
+                    break
+                }
+                sb.append(b.toChar())
+            }
+            return sb.toString()
+        }
+    }
 }

app/src/test/java/xyz/cottongin/radio247/audio/StreamConnectionTest.kt

@@ -9,6 +9,8 @@ import org.junit.Assert.assertNull
 import org.junit.Assert.assertTrue
 import org.junit.Assert.fail
 import org.junit.Test
+import java.io.ByteArrayInputStream
+import java.net.ProtocolException
 
 class StreamConnectionTest {
 
@@ -120,4 +122,105 @@ class StreamConnectionTest {
 
         conn.close()
     }
+
+    // --- ICY protocol header parsing (Shoutcast v1 support) ---
+
+    @Test
+    fun parseIcyHeaders_extracts_standard_shoutcast_headers() {
+        val raw = "ICY 200 OK\r\n" +
+            "icy-notice1:<BR>This stream requires Winamp<BR>\r\n" +
+            "icy-name:My Station\r\n" +
+            "icy-genre:Rock\r\n" +
+            "content-type:audio/mpeg\r\n" +
+            "icy-pub:1\r\n" +
+            "icy-metaint:8192\r\n" +
+            "icy-br:128\r\n" +
+            "\r\n" +
+            "audio bytes here"
+        val input = ByteArrayInputStream(raw.toByteArray(Charsets.US_ASCII))
+
+        val headers = StreamConnection.parseIcyHeaders(input)
+
+        assertEquals("8192", headers["icy-metaint"])
+        assertEquals("128", headers["icy-br"])
+        assertEquals("audio/mpeg", headers["content-type"])
+        assertEquals("My Station", headers["icy-name"])
+        assertEquals("Rock", headers["icy-genre"])
+
+        val remaining = input.readBytes().toString(Charsets.US_ASCII)
+        assertEquals("audio bytes here", remaining)
+    }
+
+    @Test
+    fun parseIcyHeaders_accepts_http_status_line() {
+        val raw = "HTTP/1.0 200 OK\r\n" +
+            "icy-metaint:16000\r\n" +
+            "Content-Type:audio/mpeg\r\n" +
+            "\r\n"
+        val headers = StreamConnection.parseIcyHeaders(
+            ByteArrayInputStream(raw.toByteArray(Charsets.US_ASCII))
+        )
+        assertEquals("16000", headers["icy-metaint"])
+        assertEquals("audio/mpeg", headers["content-type"])
+    }
+
+    @Test(expected = ConnectionFailed::class)
+    fun parseIcyHeaders_rejects_garbage_status_line() {
+        val raw = "GARBAGE\r\n\r\n"
+        StreamConnection.parseIcyHeaders(
+            ByteArrayInputStream(raw.toByteArray(Charsets.US_ASCII))
+        )
+    }
+
+    @Test
+    fun parseIcyHeaders_handles_missing_metaint() {
+        val raw = "ICY 200 OK\r\n" +
+            "content-type:audio/mpeg\r\n" +
+            "icy-br:64\r\n" +
+            "\r\n"
+        val headers = StreamConnection.parseIcyHeaders(
+            ByteArrayInputStream(raw.toByteArray(Charsets.US_ASCII))
+        )
+        assertNull(headers["icy-metaint"])
+        assertEquals("64", headers["icy-br"])
+    }
+
+    @Test
+    fun parseIcyHeaders_handles_lf_only_line_endings() {
+        val raw = "ICY 200 OK\n" +
+            "icy-metaint:4096\n" +
+            "content-type:audio/mpeg\n" +
+            "\n"
+        val headers = StreamConnection.parseIcyHeaders(
+            ByteArrayInputStream(raw.toByteArray(Charsets.US_ASCII))
+        )
+        assertEquals("4096", headers["icy-metaint"])
+    }
+
+    @Test
+    fun looksLikeIcyProtocolError_matches_protocol_exception() {
+        assertTrue(
+            StreamConnection.looksLikeIcyProtocolError(
+                ProtocolException("unexpected status line: ICY 200 OK")
+            )
+        )
+    }
+
+    @Test
+    fun looksLikeIcyProtocolError_matches_http09_message() {
+        assertTrue(
+            StreamConnection.looksLikeIcyProtocolError(
+                java.io.IOException("Received HTTP/0.9 when not allowed")
+            )
+        )
+    }
+
+    @Test
+    fun looksLikeIcyProtocolError_does_not_match_unrelated_io_error() {
+        assertTrue(
+            !StreamConnection.looksLikeIcyProtocolError(
+                java.io.IOException("Connection reset by peer")
+            )
+        )
+    }
 }