Files
AquaDX/src/main/java/icu/samnyan/aqua/sega/general/BaseHandler.kt
2025-03-11 02:48:31 -04:00

79 lines
3.0 KiB
Kotlin

package icu.samnyan.aqua.sega.general
import com.fasterxml.jackson.core.JsonProcessingException
import ext.*
import jakarta.servlet.http.HttpServletRequest
import org.springframework.scheduling.annotation.Scheduled
fun interface BaseHandler {
@Throws(JsonProcessingException::class)
fun handle(request: Map<String, Any>): Any?
}
const val MAX_COUNT = Int.MAX_VALUE / 2
class RequestContext(
val req: HttpServletRequest,
val data: MutableMap<String, Any>,
) {
val uid by lazy { parsing { data["userId"]!!.long } }
val nextIndex by lazy { parsing { data["nextIndex"]?.int ?: -1 } }
val maxCount by lazy { parsing { data["maxCount"]?.int ?: MAX_COUNT } }
}
typealias SpecialHandler = RequestContext.() -> Any?
fun BaseHandler.toSpecial() = { ctx: RequestContext -> handle(ctx.data) }
typealias PagedHandler = RequestContext.() -> List<Any>
typealias AddFn = RequestContext.() -> PagedProcessor
typealias PagePost = (MutJDict) -> Unit
data class PagedProcessor(val add: JDict?, val fn: PagedHandler, var post: PagePost? = null)
// A very :3 way of declaring APIs
abstract class MeowApi(val serialize: (String, Any) -> String) {
val initH = mutableMapOf<String, SpecialHandler>()
infix operator fun String.invoke(fn: SpecialHandler) = initH.set("${this}Api", fn)
infix fun String.static(fn: () -> Any) = serialize(this, fn()).let { resp -> this { resp } }
// Page Cache: {cache key: (timestamp, full list)}
val pageCache = mutableMapOf<String, Pair<Long, List<Any>>>()
fun String.pagedWithKind(key: String, addFn: AddFn) = this api@ {
val p = addFn()
val add = p.add ?: emptyMap()
if (nextIndex == -1) return@api p.fn(this).let { mapOf("userId" to uid, "length" to it.size, key to it) + add }
// Try to get cache
val cacheKey = "$key:$uid:$add"
val list = pageCache.getOrPut(cacheKey) { p.fn(this).let {
if (it.size > maxCount) millis() to it
else return@api mapOf("userId" to uid, "length" to it.size, "nextIndex" to -1, key to it) + add
} }.r
// Get sublist and next index
var iAfter = (nextIndex + maxCount).coerceAtMost(list.size)
val lst = list.slice(nextIndex until iAfter)
// Update cache if needed
if (iAfter == list.size) {
pageCache.remove(cacheKey)
iAfter = -1
}
else pageCache[cacheKey] = millis() to list
(mapOf("userId" to uid, "length" to lst.size, "nextIndex" to iAfter, key to lst) + add).mut
.also { p.post?.invoke(it) }
}
fun String.paged(key: String, fn: PagedHandler) = pagedWithKind(key) { PagedProcessor(null, fn) }
infix fun JDict.grabs(fn: PagedHandler) = PagedProcessor(this, fn, null)
infix fun PagedProcessor.postProcess(post: PagePost) = also { it.post = post }
// Page cache cleanup every minute
@Scheduled(fixedRate = (1000 * 60))
fun cleanupCache() {
val minTime = millis() - (1000 * 60)
pageCache.entries.removeIf { it.value.l < minTime }
}
}