feat: add progression readiness api

internal/progression/service_test.go

@@ -0,0 +1,97 @@
+package progression
+
+import (
+	"testing"
+
+	"tutor/internal/learnermemory"
+	"tutor/internal/workflows"
+)
+
+func TestReadinessMapUsesEvidenceBackedMemory(t *testing.T) {
+	service := seededService(t, workflows.ReadinessImproving)
+
+	readiness, err := service.ReadinessMap("user-1")
+	if err != nil {
+		t.Fatalf("ReadinessMap error: %v", err)
+	}
+	if readiness.ReadinessPercentage != 50 {
+		t.Fatalf("readiness = %d, want 50", readiness.ReadinessPercentage)
+	}
+	if len(readiness.Concepts) != 1 {
+		t.Fatalf("concepts = %d, want 1", len(readiness.Concepts))
+	}
+	if readiness.Concepts[0].LadderLevel != workflows.LadderTradeoffs {
+		t.Fatalf("ladder = %q", readiness.Concepts[0].LadderLevel)
+	}
+	if len(readiness.Rewards) != 1 {
+		t.Fatalf("rewards = %d, want 1", len(readiness.Rewards))
+	}
+}
+
+func TestNextChallengeTargetsWeakestConcept(t *testing.T) {
+	memory := learnermemory.NewService(learnermemory.NewMemoryStore())
+	if _, err := memory.EnsureProfile(learnermemory.ProfileInput{
+		UserID:     "user-1",
+		TargetRole: "backend developer",
+		Stack:      []string{"go"},
+	}); err != nil {
+		t.Fatalf("EnsureProfile error: %v", err)
+	}
+	evidence := []workflows.EvidenceRef{{Kind: workflows.EvidenceAnswer, ID: "a-1", Confidence: 1}}
+	if err := memory.ApplyCandidate(workflows.MemoryUpdateCandidate{
+		UserID: "user-1",
+		Updates: []workflows.MemoryUpdate{
+			{
+				Kind:          workflows.MemoryConceptMastery,
+				Concept:       workflows.ConceptRef{ID: "cache", Label: "Cache invalidation", Track: "backend-developer"},
+				ProposedState: workflows.ReadinessInterviewReady,
+				Evidence:      evidence,
+			},
+			{
+				Kind:          workflows.MemoryConceptMastery,
+				Concept:       workflows.ConceptRef{ID: "indexes", Label: "Database indexes", Track: "backend-developer"},
+				ProposedState: workflows.ReadinessFragile,
+				Evidence:      evidence,
+			},
+		},
+	}); err != nil {
+		t.Fatalf("ApplyCandidate error: %v", err)
+	}
+
+	challenge, err := NewService(memory).NextChallenge("user-1")
+	if err != nil {
+		t.Fatalf("NextChallenge error: %v", err)
+	}
+	if challenge.Concept.ID != "indexes" {
+		t.Fatalf("challenge concept = %q", challenge.Concept.ID)
+	}
+	if challenge.DifficultyAction != workflows.DifficultyRecover {
+		t.Fatalf("difficulty = %q", challenge.DifficultyAction)
+	}
+}
+
+func seededService(t *testing.T, state workflows.ReadinessState) *Service {
+	t.Helper()
+	memory := learnermemory.NewService(learnermemory.NewMemoryStore())
+	if _, err := memory.EnsureProfile(learnermemory.ProfileInput{
+		UserID:     "user-1",
+		TargetRole: "backend developer",
+		Stack:      []string{"go"},
+	}); err != nil {
+		t.Fatalf("EnsureProfile error: %v", err)
+	}
+	if err := memory.ApplyCandidate(workflows.MemoryUpdateCandidate{
+		UserID: "user-1",
+		Updates: []workflows.MemoryUpdate{
+			{
+				Kind:          workflows.MemoryConceptMastery,
+				Concept:       workflows.ConceptRef{ID: "idempotency", Label: "HTTP idempotency", Track: "backend-developer"},
+				ProposedState: state,
+				Evidence:      []workflows.EvidenceRef{{Kind: workflows.EvidenceAnswer, ID: "a-1", Confidence: 1}},
+			},
+		},
+	}); err != nil {
+		t.Fatalf("ApplyCandidate error: %v", err)
+	}
+	return NewService(memory)
+}