Implement Progression Comparison Logic and Refactor Fetching Methods

- Introduced `buildProgressionComparePayload` to create a structured comparison response from baseline and proposed evaluation results, enhancing clarity in slot differences.
- Refactored `fetchMatchCompare` to `fetchFullMatch` for improved clarity and functionality in fetching progression paths.
- Updated `runMatchCompareFlow` to streamline the evaluation process, integrating baseline and match results for a comprehensive comparison.
- Enhanced utility functions for managing slot differences and gap fill offers, improving overall data handling in the progression graph editor.
- Adjusted frontend components to reflect these changes, ensuring a more intuitive user experience in managing progression paths.

frontend/src/components/ProgressionGraphEditor.jsx

@@ -28,6 +28,7 @@ import {
   applyEvaluateResponseToDraft,
   applyGapOfferToDraft,
   applySelectedCompareSteps,
+  buildProgressionComparePayload,
   compareSlotDiffs,
   collectGapOffersFromApiResponse,
   dedupeGapOffersBySlot,
@@ -489,26 +490,26 @@ export default function ProgressionGraphEditor({ graphId, embedded = false, onSa
     }
   }
 
-  const fetchMatchCompare = async (synced) => {
-    const res = await api.suggestProgressionPath({
+  const fetchFullMatch = async (synced) =>
+    api.suggestProgressionPath({
       ...buildMatchRequestBase(synced),
-      evaluate_steps: slotsToEvaluateSteps(synced),
-      compare_with_assignments: true,
+      preserve_slot_assignments: false,
       include_llm_intent: false,
       include_llm_path_qa: false,
     })
-    if (!res?.comparison_mode) {
-      throw new Error('Kein Vergleich in der Antwort')
-    }
-    return res
-  }
 
   const runMatchCompareFlow = async (synced, { source = 'match' } = {}) => {
-    const res = await fetchMatchCompare(synced)
-    setGapFillOffers(mergeGapOffersForDraft(synced, res))
-    presentMatchCompare(res, { source })
-    setPathQa(res?.baseline_path_qa || null)
-    return res
+    setMatchNotice('Schritt 1/2: Aktuellen Pfad bewerten…')
+    const baselineRes = await fetchPathEvaluate(synced)
+    setPathQa(baselineRes?.path_qa || null)
+
+    setMatchNotice('Schritt 2/2: Match für alle Slots (Bibliothek + Lücken)…')
+    const matchRes = await fetchFullMatch(synced)
+
+    const compareRes = buildProgressionComparePayload(baselineRes, matchRes)
+    setGapFillOffers(mergeGapOffersForDraft(synced, baselineRes, matchRes))
+    presentMatchCompare(compareRes, { source })
+    return compareRes
   }
 
   const presentMatchCompare = (res, { source = 'manual' } = {}) => {

frontend/src/utils/progressionGraphDraft.js

@@ -928,6 +928,115 @@ export function draftHasLibrarySlotAssignments(draft) {
   return slotsToSlotAssignments(draft).length >= 1
 }
 
+function normalizeCompareSlotTitle(title) {
+  return (title || '').trim().toLowerCase()
+}
+
+function stepsByMajorIndex(steps) {
+  const out = new Map()
+  for (const step of steps || []) {
+    if (step?.roadmap_major_step_index == null || !Number.isFinite(Number(step.roadmap_major_step_index))) {
+      continue
+    }
+    out.set(Number(step.roadmap_major_step_index), step)
+  }
+  return out
+}
+
+function buildProgressionSlotDiffs(baselineSteps, proposedSteps) {
+  const baseBy = stepsByMajorIndex(baselineSteps)
+  const propBy = stepsByMajorIndex(proposedSteps)
+  const indices = new Set([...baseBy.keys(), ...propBy.keys()])
+  const diffs = []
+  for (const midx of [...indices].sort((a, b) => a - b)) {
+    const base = baseBy.get(midx) || {}
+    const prop = propBy.get(midx) || {}
+    const baseId = base.exercise_id
+    const propId = prop.exercise_id
+    if (baseId != null && propId != null && Number(baseId) === Number(propId)) continue
+    const baseTitle = (base.title || '').trim() || null
+    const propTitle = (prop.title || '').trim() || null
+    diffs.push({
+      roadmap_major_step_index: midx,
+      baseline_exercise_id: baseId != null ? Number(baseId) : null,
+      baseline_title: baseTitle,
+      proposed_exercise_id: propId != null ? Number(propId) : null,
+      proposed_title: propTitle,
+      baseline_slot_status: base.slot_status,
+      proposed_slot_status: prop.slot_status,
+      changed: baseId !== propId || baseTitle !== propTitle,
+    })
+  }
+  return diffs
+}
+
+function annotateCompareSlotDiffs(diffs) {
+  return (diffs || []).map((raw) => {
+    const bt = normalizeCompareSlotTitle(raw.baseline_title)
+    const pt = normalizeCompareSlotTitle(raw.proposed_title)
+    return {
+      ...raw,
+      trivial_id_swap: Boolean(bt && pt && bt === pt),
+    }
+  })
+}
+
+function actionableCompareSlotDiffs(diffs) {
+  return (diffs || []).filter((d) => !d.trivial_id_swap)
+}
+
+function mergeGapFillOffersFromSteps(steps, offers) {
+  const merged = (offers || []).map((o) => ({ ...o }))
+  const seen = new Set(merged.map((o) => o.offer_id).filter(Boolean))
+  for (const step of steps || []) {
+    const go = step?.gap_offer
+    if (!go || typeof go !== 'object') continue
+    if (go.offer_id && seen.has(go.offer_id)) continue
+    if (go.offer_id) seen.add(go.offer_id)
+    merged.push({ ...go })
+  }
+  return merged
+}
+
+/**
+ * Vergleich aus zwei kaskadierten Antworten (Evaluate → Match) — spiegelt Backend-Compare.
+ */
+export function buildProgressionComparePayload(baselineRes, proposedRes) {
+  const baselineSteps = Array.isArray(baselineRes?.steps) ? baselineRes.steps : []
+  const proposedSteps = Array.isArray(proposedRes?.steps) ? proposedRes.steps : []
+  const baselineQa = baselineRes?.path_qa || null
+  const pipelineQa = proposedRes?.path_qa || null
+  const slotDiffs = annotateCompareSlotDiffs(
+    buildProgressionSlotDiffs(baselineSteps, proposedSteps),
+  )
+  const actionableDiffs = actionableCompareSlotDiffs(slotDiffs)
+  const gapFillOffers = mergeGapFillOffersFromSteps(
+    proposedSteps,
+    proposedRes?.gap_fill_offers || [],
+  )
+  const proposedQa =
+    actionableDiffs.length === 0 && baselineQa ? baselineQa : pipelineQa
+
+  return {
+    ...proposedRes,
+    comparison_mode: true,
+    baseline_steps: baselineSteps,
+    baseline_path_qa: baselineQa,
+    proposed_steps: proposedSteps,
+    proposed_steps_pipeline: proposedSteps,
+    proposed_path_qa: proposedQa,
+    proposed_path_qa_pipeline: pipelineQa,
+    gap_fill_offers: gapFillOffers,
+    slot_diffs: slotDiffs,
+    slot_diffs_actionable: actionableDiffs,
+    slot_diff_count: actionableDiffs.length,
+    slot_diff_count_including_trivial: slotDiffs.length,
+    slot_diffs_source: 'steps',
+    path_qa: proposedQa,
+    steps: proposedSteps,
+  }
+}
+
 /** Alle Slot-Diffs inkl. reiner ID-Tausche (gleicher Titel). */
 export function compareSlotDiffs(comparison, { actionableOnly = false } = {}) {
   if (actionableOnly && Array.isArray(comparison?.slot_diffs_actionable)) {