🚧 Add no-negative identity filter

[Sone.git] / src / main / kotlin / net / pterodactylus / sone / freenet / wot / NoNegativeIdentityFilter.kt

diff --git a/src/main/kotlin/net/pterodactylus/sone/freenet/wot/NoNegativeIdentityFilter.kt b/src/main/kotlin/net/pterodactylus/sone/freenet/wot/NoNegativeIdentityFilter.kt
new file mode 100644 (file)
index 0000000..44468f2
--- /dev/null
+++ b/src/main/kotlin/net/pterodactylus/sone/freenet/wot/NoNegativeIdentityFilter.kt
@@ -0,0 +1,37 @@
+package net.pterodactylus.sone.freenet.wot
+
+/**
+ * Filter for identities that retains only those remote identities that do
+ * not have a single negative trust value (explicit or implicit) from any own
+ * identity.
+ */
+class NoNegativeIdentityFilter {
+
+       fun filter(identities: Map<OwnIdentity, Set<Identity>>) =
+               identities.run {
+                       val identitiesWithTrust = values.flatten()
+                               .groupBy { it.id }
+                               .mapValues { (_, identities) ->
+                                       identities.reduce { accIdentity, identity ->
+                                               identity.trust.forEach { (ownIdentity: OwnIdentity?, trust: Trust?) ->
+                                                       accIdentity.setTrust(ownIdentity, trust)
+                                               }
+                                               accIdentity
+                                       }
+                               }
+
+                       mapValues { (_, trustedIdentities) ->
+                               trustedIdentities.filter { trustedIdentity ->
+                                       identitiesWithTrust[trustedIdentity.id]!!.trust.all { it.value.hasZeroOrPositiveTrust() }
+                               }
+                       }
+               }
+
+}
+
+private fun Trust.hasZeroOrPositiveTrust() =
+               if (explicit == null) {
+                       implicit == null || implicit >= 0
+               } else {
+                       explicit >= 0
+               }