Add guest document SSE stream

src/main/kotlin/com/android/trisolarisserver/component/GuestDocumentEvents.kt

@@ -0,0 +1,108 @@
+package com.android.trisolarisserver.component
+
+import com.android.trisolarisserver.controller.GuestDocumentResponse
+import com.android.trisolarisserver.db.repo.GuestDocumentRepo
+import com.android.trisolarisserver.models.booking.GuestDocument
+import com.fasterxml.jackson.databind.ObjectMapper
+import org.springframework.scheduling.annotation.Scheduled
+import org.springframework.stereotype.Component
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter
+import java.io.IOException
+import java.util.UUID
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.CopyOnWriteArrayList
+
+@Component
+class GuestDocumentEvents(
+    private val guestDocumentRepo: GuestDocumentRepo,
+    private val objectMapper: ObjectMapper
+) {
+    private val emitters: MutableMap<GuestDocKey, CopyOnWriteArrayList<SseEmitter>> = ConcurrentHashMap()
+
+    fun subscribe(propertyId: UUID, guestId: UUID): SseEmitter {
+        val key = GuestDocKey(propertyId, guestId)
+        val emitter = SseEmitter(0L)
+        emitters.computeIfAbsent(key) { CopyOnWriteArrayList() }.add(emitter)
+        emitter.onCompletion { emitters[key]?.remove(emitter) }
+        emitter.onTimeout { emitters[key]?.remove(emitter) }
+        emitter.onError { emitters[key]?.remove(emitter) }
+        try {
+            emitter.send(SseEmitter.event().name("guest-documents").data(buildSnapshot(propertyId, guestId)))
+        } catch (_: IOException) {
+            emitters[key]?.remove(emitter)
+        }
+        return emitter
+    }
+
+    fun emit(propertyId: UUID, guestId: UUID) {
+        val key = GuestDocKey(propertyId, guestId)
+        val list = emitters[key] ?: return
+        val data = buildSnapshot(propertyId, guestId)
+        val dead = mutableListOf<SseEmitter>()
+        for (emitter in list) {
+            try {
+                emitter.send(SseEmitter.event().name("guest-documents").data(data))
+            } catch (_: IOException) {
+                dead.add(emitter)
+            }
+        }
+        if (dead.isNotEmpty()) {
+            list.removeAll(dead.toSet())
+        }
+    }
+
+    @Scheduled(fixedDelayString = "25000")
+    fun heartbeat() {
+        emitters.forEach { (_, list) ->
+            val dead = mutableListOf<SseEmitter>()
+            for (emitter in list) {
+                try {
+                    emitter.send(SseEmitter.event().name("ping").data("ok"))
+                } catch (_: IOException) {
+                    dead.add(emitter)
+                }
+            }
+            if (dead.isNotEmpty()) {
+                list.removeAll(dead.toSet())
+            }
+        }
+    }
+
+    private fun buildSnapshot(propertyId: UUID, guestId: UUID): List<GuestDocumentResponse> {
+        return guestDocumentRepo
+            .findByPropertyIdAndGuestIdOrderByUploadedAtDesc(propertyId, guestId)
+            .map { it.toResponse(objectMapper) }
+    }
+}
+
+private data class GuestDocKey(
+    val propertyId: UUID,
+    val guestId: UUID
+)
+
+private fun GuestDocument.toResponse(objectMapper: ObjectMapper): GuestDocumentResponse {
+    val id = id ?: throw IllegalStateException("Document id missing")
+    val extracted: Map<String, String>? = extractedData?.let {
+        try {
+            val raw = objectMapper.readValue(it, Map::class.java)
+            raw.entries.associate { entry ->
+                entry.key.toString() to (entry.value?.toString() ?: "")
+            }
+        } catch (_: Exception) {
+            null
+        }
+    }
+    return GuestDocumentResponse(
+        id = id,
+        propertyId = property.id!!,
+        guestId = guest.id!!,
+        bookingId = booking.id!!,
+        uploadedByUserId = uploadedBy.id!!,
+        uploadedAt = uploadedAt.toString(),
+        originalFilename = originalFilename,
+        contentType = contentType,
+        sizeBytes = sizeBytes,
+        extractedData = extracted,
+        extractedAt = extractedAt?.toString()
+    )
+}