+ )
+}
diff --git a/app/tutor/profile/actions.ts b/app/tutor/profile/actions.ts
new file mode 100644
index 0000000..f8713d2
--- /dev/null
+++ b/app/tutor/profile/actions.ts
@@ -0,0 +1,79 @@
+// E6 T6.1: Server action to save/update the tutor profile
+// Closes #40
+
+'use server'
+
+import { createClient } from '@/lib/supabase/server'
+import { revalidatePath } from 'next/cache'
+
+type SubjectEntry = { subject_id: number; level: 'o_levels' | 'a_levels' }
+type AvailabilityWindow = { day: number; start: string; end: string }
+
+export async function saveTutorProfile(
+ bio: string,
+ timezone: string,
+ subjects: SubjectEntry[],
+ availability: AvailabilityWindow[]
+): Promise<{ error?: string }> {
+ const supabase = await createClient()
+ const {
+ data: { user },
+ } = await supabase.auth.getUser()
+
+ if (!user) return { error: 'Not authenticated' }
+
+ // 1. Upsert tutor_profiles (approved stays false on first insert; admin controls it)
+ const { error: profileError } = await supabase.from('tutor_profiles').upsert({
+ tutor_user_id: user.id,
+ bio,
+ timezone,
+ })
+ if (profileError) return { error: `Failed to save profile: ${profileError.message}` }
+
+ // 2. Update tutor_subjects safely: upsert provided rows, then delete stale ones.
+ // This avoids the partial-failure window of delete-then-insert (where a failed
+ // insert would leave the tutor with no subjects).
+ if (subjects.length > 0) {
+ const { error: upsertError } = await supabase.from('tutor_subjects').upsert(
+ subjects.map((s) => ({ tutor_user_id: user.id, subject_id: s.subject_id, level: s.level })),
+ { onConflict: 'tutor_user_id,subject_id,level' }
+ )
+ if (upsertError) return { error: `Failed to save subjects: ${upsertError.message}` }
+ }
+
+ // Remove stale (subject_id, level) combinations that are no longer in the new list.
+ // Fetch current subjects, compute the diff, and delete only the removed ones.
+ const { data: currentSubjects, error: fetchError } = await supabase
+ .from('tutor_subjects')
+ .select('subject_id, level')
+ .eq('tutor_user_id', user.id)
+ if (fetchError) return { error: `Failed to read subjects: ${fetchError.message}` }
+
+ const newKeys = new Set(subjects.map((s) => `${s.subject_id}:${s.level}`))
+ const toDelete = (currentSubjects ?? []).filter(
+ (row) => !newKeys.has(`${row.subject_id}:${row.level}`)
+ )
+ if (toDelete.length > 0) {
+ // Build a single OR-filter to remove all stale rows in one round-trip instead of N.
+ // Syntax: and(subject_id.eq.X,level.eq.Y) per stale pair, joined by comma = OR.
+ const orFilter = toDelete
+ .map((row) => `and(subject_id.eq.${row.subject_id},level.eq.${row.level})`)
+ .join(',')
+ const { error: delError } = await supabase
+ .from('tutor_subjects')
+ .delete()
+ .eq('tutor_user_id', user.id)
+ .or(orFilter)
+ if (delError) return { error: `Failed to remove old subjects: ${delError.message}` }
+ }
+
+ // 3. Upsert tutor_availability
+ const { error: availError } = await supabase.from('tutor_availability').upsert({
+ tutor_user_id: user.id,
+ windows: availability,
+ })
+ if (availError) return { error: `Failed to save availability: ${availError.message}` }
+
+ revalidatePath('/tutor/profile')
+ return {}
+}
diff --git a/app/tutor/profile/page.tsx b/app/tutor/profile/page.tsx
index e1125f5..fd37ee5 100644
--- a/app/tutor/profile/page.tsx
+++ b/app/tutor/profile/page.tsx
@@ -1 +1,99 @@
-export default function Page() { return