1 files changed, 100 insertions, 0 deletions
diff --git a/src/lib/moderation/useLabelInfo.ts b/src/lib/moderation/useLabelInfo.ts
new file mode 100644
index 000000000..b1cffe1e7
--- /dev/null
+++ b/src/lib/moderation/useLabelInfo.ts
@@ -0,0 +1,100 @@
+import {
+  ComAtprotoLabelDefs,
+  AppBskyLabelerDefs,
+  LABELS,
+  interpretLabelValueDefinition,
+  InterpretedLabelValueDefinition,
+} from '@atproto/api'
+import {useLingui} from '@lingui/react'
+import * as bcp47Match from 'bcp-47-match'
+
+import {
+  GlobalLabelStrings,
+  useGlobalLabelStrings,
+} from '#/lib/moderation/useGlobalLabelStrings'
+import {useLabelDefinitions} from '#/state/preferences'
+
+export interface LabelInfo {
+  label: ComAtprotoLabelDefs.Label
+  def: InterpretedLabelValueDefinition
+  strings: ComAtprotoLabelDefs.LabelValueDefinitionStrings
+  labeler: AppBskyLabelerDefs.LabelerViewDetailed | undefined
+}
+
+export function useLabelInfo(label: ComAtprotoLabelDefs.Label): LabelInfo {
+  const {i18n} = useLingui()
+  const {labelDefs, labelers} = useLabelDefinitions()
+  const globalLabelStrings = useGlobalLabelStrings()
+  const def = getDefinition(labelDefs, label)
+  return {
+    label,
+    def,
+    strings: getLabelStrings(i18n.locale, globalLabelStrings, def),
+    labeler: labelers.find(labeler => label.src === labeler.creator.did),
+  }
+}
+
+export function getDefinition(
+  labelDefs: Record<string, InterpretedLabelValueDefinition[]>,
+  label: ComAtprotoLabelDefs.Label,
+): InterpretedLabelValueDefinition {
+  // check local definitions
+  const customDef =
+    !label.val.startsWith('!') &&
+    labelDefs[label.src]?.find(
+      def => def.identifier === label.val && def.definedBy === label.src,
+    )
+  if (customDef) {
+    return customDef
+  }
+
+  // check global definitions
+  const globalDef = LABELS[label.val as keyof typeof LABELS]
+  if (globalDef) {
+    return globalDef
+  }
+
+  // fallback to a noop definition
+  return interpretLabelValueDefinition(
+    {
+      identifier: label.val,
+      severity: 'none',
+      blurs: 'none',
+      defaultSetting: 'ignore',
+      locales: [],
+    },
+    label.src,
+  )
+}
+
+export function getLabelStrings(
+  locale: string,
+  globalLabelStrings: GlobalLabelStrings,
+  def: InterpretedLabelValueDefinition,
+): ComAtprotoLabelDefs.LabelValueDefinitionStrings {
+  if (!def.definedBy) {
+    // global definition, look up strings
+    if (def.identifier in globalLabelStrings) {
+      return globalLabelStrings[
+        def.identifier
+      ] as ComAtprotoLabelDefs.LabelValueDefinitionStrings
+    }
+  } else {
+    // try to find locale match in the definition's strings
+    const localeMatch = def.locales.find(
+      strings => bcp47Match.basicFilter(locale, strings.lang).length > 0,
+    )
+    if (localeMatch) {
+      return localeMatch
+    }
+    // fall back to the zero item if no match
+    if (def.locales[0]) {
+      return def.locales[0]
+    }
+  }
+  return {
+    lang: locale,
+    name: def.identifier,
+    description: `Labeled "${def.identifier}"`,
+  }
+}