From 88cc780a3c238d379c8639997033061c6003f220 Mon Sep 17 00:00:00 2001
From: HopeBaron <truehope9000@gmail.com>
Date: Thu, 25 Jun 2020 20:51:27 +0300
Subject: [PATCH] Fix getGuildMembers for suppliers

---
 CHANGELOG.md                                  |  6 +++++
 .../kordlib/core/behavior/GuildBehavior.kt    |  2 +-
 .../core/supplier/CacheEntitySupplier.kt      |  3 ++-
 .../core/supplier/RestEntitySupplier.kt       | 25 +++++++++++++++----
 4 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 93cf7c2a1cb..13a28149219 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# 0.5.3
+
+## Fixes
+
+* `getGuildMembers` returns the correct limit for both Cache and Rest suppliers.
+
 # 0.5.2
 ## Additions
 * Add missing mention property for unicode emojis.
diff --git a/core/src/main/kotlin/com/gitlab/kordlib/core/behavior/GuildBehavior.kt b/core/src/main/kotlin/com/gitlab/kordlib/core/behavior/GuildBehavior.kt
index 51828abd0f6..c102f2a75c5 100644
--- a/core/src/main/kotlin/com/gitlab/kordlib/core/behavior/GuildBehavior.kt
+++ b/core/src/main/kotlin/com/gitlab/kordlib/core/behavior/GuildBehavior.kt
@@ -100,7 +100,7 @@ interface GuildBehavior : Entity, Strategizable {
      * [terminal operators](https://kotlinlang.org/docs/reference/coroutines/flow.html#terminal-flow-operators) instead.
      */
     val members: Flow<Member>
-        get() = supplier.getGuildMembers(id, 1000)
+        get() = supplier.getGuildMembers(id)
 
     /**
      * Requests to get the present voice regions for this guild.
diff --git a/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/CacheEntitySupplier.kt b/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/CacheEntitySupplier.kt
index ba56bd3d561..636258d7378 100644
--- a/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/CacheEntitySupplier.kt
+++ b/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/CacheEntitySupplier.kt
@@ -176,11 +176,12 @@ class CacheEntitySupplier(private val kord: Kord) : EntitySupplier {
     }.asFlow().map { Ban(it, kord) }
 
     override fun getGuildMembers(guildId: Snowflake, limit: Int): Flow<Member> {
+        require(limit > 0) { "At least 1 item should be requested, but got $limit." }
         return kord.cache.query<UserData>().asFlow().flatMapConcat { userData ->
             kord.cache.query<MemberData> {
                 MemberData::userId eq userData.id
                 MemberData::guildId eq guildId
-            }.asFlow().map { Member(it, userData, kord) }
+            }.asFlow().map { Member(it, userData, kord) }.take(limit)
         }
     }
 
diff --git a/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/RestEntitySupplier.kt b/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/RestEntitySupplier.kt
index 6d4b3048916..3c8c9b60d5f 100644
--- a/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/RestEntitySupplier.kt
+++ b/core/src/main/kotlin/com/gitlab/kordlib/core/supplier/RestEntitySupplier.kt
@@ -1,5 +1,6 @@
 package com.gitlab.kordlib.core.supplier
 
+import com.gitlab.kordlib.common.entity.DiscordGuildMember
 import com.gitlab.kordlib.common.entity.DiscordPartialGuild
 import com.gitlab.kordlib.common.entity.Snowflake
 import com.gitlab.kordlib.core.Kord
@@ -88,8 +89,9 @@ class RestEntitySupplier(val kord: Kord) : EntitySupplier {
     }
 
     override suspend fun getMemberOrNull(guildId: Snowflake, userId: Snowflake): Member? = catchNotFound {
-        val memberData = guild.getGuildMember(guildId = guildId.value, userId = userId.value).toData(guildId = guildId.value, userId = userId.value)
-        val userData = user.getUser(userId.value).toData()
+        val member = guild.getGuildMember(guildId = guildId.value, userId = userId.value)
+        val memberData = member.toData(guildId = guildId.value, userId = userId.value)
+        val userData = member.user!!.toData()
         return Member(memberData, userData, kord)
     }
 
@@ -158,11 +160,24 @@ class RestEntitySupplier(val kord: Kord) : EntitySupplier {
             emit(Ban(BanData.from(guildId.value, banData), kord))
     }
 
-    override fun getGuildMembers(guildId: Snowflake, limit: Int): Flow<Member> = flow {
-        for (memberData in guild.getGuildMembers(guildId.value))
-            emit(Member(memberData.toData(memberData.user!!.id, guildId.value), memberData.user!!.toData(), kord))
+    override fun getGuildMembers(guildId: Snowflake, limit: Int): Flow<Member> {
+        require(limit > 0) { "At least 1 item should be requested, but got $limit." }
+        val batchSize = min(1000, limit)
+
+        val flow = paginateForwards(idSelector = { it.user!!.id }, batchSize = batchSize) { position ->
+            kord.rest.guild.getGuildMembers(guildId = guildId.value, position = position, limit = batchSize)
+        }.map {
+            val userData = it.user!!.toData()
+            val memberData = it.toData(guildId = guildId.value, userId = it.user!!.id)
+            Member(memberData, userData, kord)
+        }
+
+
+        return if (limit != Int.MAX_VALUE) flow.take(limit)
+        else flow
     }
 
+
     override fun getGuildVoiceRegions(guildId: Snowflake): Flow<Region> = flow {
         for (region in guild.getGuildVoiceRegions(guildId.value)) {
             val data = RegionData.from(guildId.value, region)