Fix accessibility recognition idempotency

frontend/android/app/src/main/kotlin/com/nx/miaoji/RecognitionStore.kt

@@ -102,9 +102,11 @@ class RecognitionStore(context: Context) :
                 PaymentParser.sha256("${signal.packageName}|flow|$it")
             }
             val strongKey = orderStrongKey ?: flowStrongKey
+            val clientRequestId = clientRequestIdFor(signal)
             val signalHigh = signal.channel in setOf("accessibility", "local_ocr") &&
                 signal.evidenceConfidence == "high"
             val existing = findMergeCandidate(signal, channelBit, merchantHash, strongKey, now)
+                ?: findByClientRequestId(clientRequestId)
             val id: String
             if (existing != null) {
                 id = existing.id
@@ -123,6 +125,7 @@ class RecognitionStore(context: Context) :
                         put("known_template", if (existing.knownTemplate || signal.knownTemplate) 1 else 0)
                         put("high_confidence", if (high) 1 else 0)
                         put("payload_encrypted", encryptPayload(mergedPayload))
+                        if (high && existing.state == "pending_confirm") put("state", "auto_ready")
                         put("updated_at", now)
                         put("available_at", now + MERGE_DELAY_MS)
                     },
@@ -138,7 +141,7 @@ class RecognitionStore(context: Context) :
                     null,
                     ContentValues().apply {
                         put("id", id)
-                        put("client_request_id", "recognition-$id")
+                        put("client_request_id", clientRequestId)
                         put("package_name", signal.packageName)
                         put("amount_cents", signal.amountCents)
                         put("direction", signal.type)
@@ -173,6 +176,14 @@ class RecognitionStore(context: Context) :
         }
     }
 
+    private fun findByClientRequestId(clientRequestId: String): CandidateRow? =
+        readableDatabase.rawQuery(
+            "SELECT * FROM candidates WHERE client_request_id = ? AND state NOT IN ('undone','expired') LIMIT 1",
+            arrayOf(clientRequestId),
+        ).use { cursor ->
+            if (cursor.moveToFirst()) row(cursor) else null
+        }
+
     @Synchronized
     fun finalizeCandidate(id: String): StoredCandidate? {
         val now = System.currentTimeMillis()
@@ -267,7 +278,6 @@ class RecognitionStore(context: Context) :
                 if (cursor.moveToFirst()) return row(cursor)
             }
         }
-        if (signal.channel == "local_ocr" && signal.flowSessionId != null) return null
         val since = signal.occurredAtEpochMs - NO_ORDER_WINDOW_MS
         val until = signal.occurredAtEpochMs + NO_ORDER_WINDOW_MS
         readableDatabase.rawQuery(
@@ -291,7 +301,12 @@ class RecognitionStore(context: Context) :
             while (cursor.moveToNext()) {
                 val candidate = row(cursor)
                 val hasSameChannel = candidate.channelMask and channelBit != 0
-                if (!hasSameChannel || now - candidate.updatedAt <= SAME_CHANNEL_DEBOUNCE_MS) {
+                val sameResult = signal.resultFingerprint != null &&
+                    signal.resultFingerprint == candidate.resultFingerprint
+                if (sameResult ||
+                    !hasSameChannel ||
+                    now - candidate.updatedAt <= SAME_CHANNEL_DEBOUNCE_MS
+                ) {
                     return candidate
                 }
             }
@@ -330,10 +345,12 @@ class RecognitionStore(context: Context) :
             ?: JSONObject()
         return CandidateRow(
             id = cursor.getString(cursor.getColumnIndexOrThrow("id")),
+            state = cursor.getString(cursor.getColumnIndexOrThrow("state")),
             channelMask = cursor.getInt(cursor.getColumnIndexOrThrow("channel_mask")),
             knownTemplate = cursor.getInt(cursor.getColumnIndexOrThrow("known_template")) == 1,
             highConfidence = cursor.getInt(cursor.getColumnIndexOrThrow("high_confidence")) == 1,
             updatedAt = cursor.getLong(cursor.getColumnIndexOrThrow("updated_at")),
+            resultFingerprint = payload.optString("resultFingerprint").takeIf(String::isNotBlank),
             payload = payload,
         )
     }
@@ -411,10 +428,12 @@ class RecognitionStore(context: Context) :
 
     private data class CandidateRow(
         val id: String,
+        val state: String,
         val channelMask: Int,
         val knownTemplate: Boolean,
         val highConfidence: Boolean,
         val updatedAt: Long,
+        val resultFingerprint: String?,
         val payload: JSONObject,
     )
 
@@ -424,5 +443,17 @@ class RecognitionStore(context: Context) :
         private const val NO_ORDER_WINDOW_MS = 90_000L
         private const val SAME_CHANNEL_DEBOUNCE_MS = 10_000L
         private const val EXPIRE_MS = 7L * 24L * 60L * 60L * 1000L
+
+        internal fun clientRequestIdFor(signal: PaymentSignal): String {
+            val basis = when {
+                !signal.orderId.isNullOrBlank() ->
+                    "${signal.packageName}|order|${signal.orderId.trim()}"
+                !signal.flowSessionId.isNullOrBlank() ->
+                    "${signal.packageName}|flow|${signal.flowSessionId}"
+                else ->
+                    "${signal.packageName}|event|${signal.sourceEventId}"
+            }
+            return "recognition-${PaymentParser.sha256(basis).take(52)}"
+        }
     }
 }

frontend/android/app/src/test/kotlin/com/nx/miaoji/PaymentParserTest.kt

@@ -2,6 +2,7 @@ package com.nx.miaoji
 
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNotEquals
 import org.junit.Assert.assertNull
 import org.junit.Assert.assertTrue
 import org.junit.Test
@@ -254,4 +255,73 @@ class PaymentParserTest {
         assertFalse(preview.contains("丁伊文"))
         assertFalse(preview.contains("202607221234567890"))
     }
+
+    @Test
+    fun recognitionClientRequestIdIsStableWithinPaymentFlow() {
+        val treeSignal = paymentSignal(
+            channel = "accessibility",
+            sourceEventId = "a:wechat:flow-123",
+            flowSessionId = "flow-123",
+        )
+        val ocrSignal = paymentSignal(
+            channel = "local_ocr",
+            sourceEventId = "ocr:wechat:flow-123",
+            flowSessionId = "flow-123",
+        )
+        val otherFlow = paymentSignal(
+            channel = "accessibility",
+            sourceEventId = "a:wechat:flow-456",
+            flowSessionId = "flow-456",
+        )
+
+        val requestId = RecognitionStore.clientRequestIdFor(treeSignal)
+        assertEquals(requestId, RecognitionStore.clientRequestIdFor(ocrSignal))
+        assertNotEquals(requestId, RecognitionStore.clientRequestIdFor(otherFlow))
+        assertTrue(requestId.length <= 64)
+    }
+
+    @Test
+    fun recognitionClientRequestIdPrefersOrderIdAcrossFlows() {
+        val first = paymentSignal(
+            channel = "accessibility",
+            sourceEventId = "a:wechat:flow-a",
+            flowSessionId = "flow-a",
+            orderId = "202607251234567890",
+        )
+        val second = paymentSignal(
+            channel = "local_ocr",
+            sourceEventId = "ocr:wechat:flow-b",
+            flowSessionId = "flow-b",
+            orderId = "202607251234567890",
+        )
+
+        assertEquals(
+            RecognitionStore.clientRequestIdFor(first),
+            RecognitionStore.clientRequestIdFor(second),
+        )
+    }
+
+    private fun paymentSignal(
+        channel: String,
+        sourceEventId: String,
+        flowSessionId: String?,
+        orderId: String? = null,
+    ): PaymentSignal = PaymentSignal(
+        packageName = PaymentParser.WECHAT,
+        channel = channel,
+        amountCents = 2_000L,
+        type = "expense",
+        merchant = "测试商户",
+        orderId = orderId,
+        occurredAtEpochMs = 1_000L,
+        knownTemplate = true,
+        sourceEventId = sourceEventId,
+        sourceText = "测试支付",
+        flowSessionId = flowSessionId,
+        evidenceConfidence = "high",
+        recognitionKind = "payment",
+        categoryHint = null,
+        amountSource = "result",
+        resultFingerprint = "fingerprint",
+    )
 }