refactor: streamline exercise selection process in training pages

- Simplified the exercise selection logic in TrainingUnitSectionsEditor, TrainingFrameworkProgramEditPage, and TrainingPlanningPage by removing the multi-select option.
- Updated the ExercisePickerModal to always enable multi-select, enhancing user experience when selecting exercises.
- Refactored the handling of selected exercises to improve clarity and maintainability of the code.

frontend/src/components/TrainingUnitSectionsEditor.jsx

@@ -809,19 +809,10 @@ export default function TrainingUnitSectionsEditor({
                 <button
                   type="button"
                   className="btn btn-secondary framework-ctrl framework-ctrl--xs"
-                  onClick={() => addItem(sIdx, 'exercise')}
+                  onClick={() => onRequestExercisePick?.({ sectionIndex: sIdx })}
                 >
                   + Übung
                 </button>
-                <button
-                  type="button"
-                  className="btn btn-secondary framework-ctrl framework-ctrl--xs"
-                  onClick={() =>
-                    onRequestExercisePick?.({ sectionIndex: sIdx, multi: true })
-                  }
-                >
-                  + mehrere Übungen…
-                </button>
                 <button
                   type="button"
                   className="btn btn-secondary framework-ctrl framework-ctrl--xs"

frontend/src/pages/TrainingFrameworkProgramEditPage.jsx

@@ -627,12 +627,11 @@ export default function TrainingFrameworkProgramEditPage() {
                 ),
               }))
             }}
-            onRequestExercisePick={({ sectionIndex, itemIndex, multi }) =>
+            onRequestExercisePick={({ sectionIndex, itemIndex }) =>
               setSectionPickerCtx({
                 slotIdx: si,
                 sectionIndex,
                 itemIndex: typeof itemIndex === 'number' ? itemIndex : undefined,
-                multi: !!multi,
               })
             }
             onPeekExercise={(id, variantId) =>
@@ -1108,75 +1107,45 @@ export default function TrainingFrameworkProgramEditPage() {
 
       <ExercisePickerModal
         open={sectionPickerCtx != null}
-        multiSelect={!!sectionPickerCtx?.multi}
+        multiSelect
         onClose={() => setSectionPickerCtx(null)}
-        onSelectExercises={
-          sectionPickerCtx?.multi
-            ? async (picked) => {
-                if (!sectionPickerCtx || !picked?.length) return
-                const { slotIdx, sectionIndex: sIdx } = sectionPickerCtx
-                const rows = []
-                for (const ex of picked) {
-                  const row = await hydrateExercisePlanningRow(ex)
-                  if (row) rows.push(row)
-                }
-                if (!rows.length) return
-                setForm((prev) => ({
-                  ...prev,
-                  slots: prev.slots.map((sl, ii) =>
-                    ii !== slotIdx
-                      ? sl
-                      : {
-                          ...sl,
-                          sections: (
-                            sl.sections && sl.sections.length ? sl.sections : [defaultSection('Ablauf')]
-                          ).map((sec, si) =>
-                            si !== sIdx ? sec : { ...sec, items: [...(sec.items || []), ...rows] }
-                          ),
-                        }
-                  ),
-                }))
-                setSectionPickerCtx(null)
-              }
-            : undefined
-        }
-        onSelectExercise={async (exercise) => {
-          if (!sectionPickerCtx) return
-          if (sectionPickerCtx.multi) return
-          if (typeof sectionPickerCtx.itemIndex !== 'number') return
+        onSelectExercises={async (picked) => {
+          if (!sectionPickerCtx || !picked?.length) return
+          const rows = []
+          for (const ex of picked) {
+            const row = await hydrateExercisePlanningRow(ex)
+            if (row) rows.push(row)
+          }
+          if (!rows.length) return
           const { slotIdx, sectionIndex: sIdx, itemIndex: iIdx } = sectionPickerCtx
-          const row = await hydrateExercisePlanningRow(exercise)
-          if (!row) return
           setForm((prev) => ({
             ...prev,
-            slots: prev.slots.map((sl, ii) =>
-              ii !== slotIdx
-                ? sl
-                : {
-                    ...sl,
-                    sections: (sl.sections && sl.sections.length ? sl.sections : [defaultSection('Ablauf')]).map(
-                      (sec, si) =>
-                        si !== sIdx
-                          ? sec
-                          : {
-                              ...sec,
-                              items: (sec.items || []).map((r2, ji) =>
-                                ji !== iIdx
-                                  ? r2
-                                  : r2.item_type !== 'exercise'
-                                    ? r2
-                                    : {
-                                        ...r2,
-                                        exercise_id: row.exercise_id,
-                                        exercise_variant_id: row.exercise_variant_id,
-                                        exercise_title: row.exercise_title,
-                                        variants: row.variants,
-                                      }
-                              ),
-                            }
-                    ),
+            slots: prev.slots.map((sl, ii) => {
+              if (ii !== slotIdx) return sl
+              const baseSecs = sl.sections && sl.sections.length ? sl.sections : [defaultSection('Ablauf')]
+              return {
+                ...sl,
+                sections: baseSecs.map((sec, si) => {
+                  if (si !== sIdx) return sec
+                  const items = [...(sec.items || [])]
+                  if (typeof iIdx === 'number') {
+                    const cur = items[iIdx]
+                    if (!cur || cur.item_type !== 'exercise') return sec
+                    const [first, ...tail] = rows
+                    items[iIdx] = {
+                      ...cur,
+                      exercise_id: first.exercise_id,
+                      exercise_variant_id: first.exercise_variant_id,
+                      exercise_title: first.exercise_title,
+                      variants: first.variants,
+                    }
+                    if (tail.length) items.splice(iIdx + 1, 0, ...tail)
+                    return { ...sec, items }
                   }
-            ),
+                  return { ...sec, items: [...items, ...rows] }
+                }),
+              }
+            }),
           }))
           setSectionPickerCtx(null)
         }}

frontend/src/pages/TrainingPlanningPage.jsx

@@ -709,11 +709,10 @@ function TrainingPlanningPage() {
                       sections: updater(prev.sections),
                     }))
                   }
-                  onRequestExercisePick={({ sectionIndex, itemIndex, multi }) => {
+                  onRequestExercisePick={({ sectionIndex, itemIndex }) => {
                     setExercisePickerTarget({
                       sIdx: sectionIndex,
                       iIdx: typeof itemIndex === 'number' ? itemIndex : undefined,
-                      multi: !!multi,
                     })
                     setExercisePickerOpen(true)
                   }}
@@ -824,61 +823,41 @@ function TrainingPlanningPage() {
         )}
       <ExercisePickerModal
         open={exercisePickerOpen}
-        multiSelect={!!exercisePickerTarget?.multi}
+        multiSelect
         onClose={() => {
           setExercisePickerOpen(false)
           setExercisePickerTarget(null)
         }}
-        onSelectExercises={
-          exercisePickerTarget?.multi
-            ? async (picked) => {
-                if (!exercisePickerTarget || !picked?.length) return
-                const { sIdx } = exercisePickerTarget
-                const rows = []
-                for (const ex of picked) {
-                  const row = await hydrateExercisePlanningRow(ex)
-                  if (row) rows.push(row)
-                }
-                if (!rows.length) return
-                setFormData((prev) => ({
-                  ...prev,
-                  sections: prev.sections.map((s, si) =>
-                    si !== sIdx ? s : { ...s, items: [...(s.items || []), ...rows] }
-                  ),
-                }))
-                setExercisePickerOpen(false)
-                setExercisePickerTarget(null)
-              }
-            : undefined
-        }
-        onSelectExercise={async (ex) => {
-          if (!exercisePickerTarget || exercisePickerTarget.multi) return
-          const row = await hydrateExercisePlanningRow(ex)
-          if (!row) return
+        onSelectExercises={async (picked) => {
+          if (!exercisePickerTarget || !picked?.length) return
+          const rows = []
+          for (const ex of picked) {
+            const row = await hydrateExercisePlanningRow(ex)
+            if (row) rows.push(row)
+          }
+          if (!rows.length) return
           const { sIdx, iIdx } = exercisePickerTarget
-          if (typeof iIdx !== 'number') return
           setFormData((prev) => ({
             ...prev,
-            sections: prev.sections.map((s, si) =>
-              si !== sIdx
-                ? s
-                : {
-                    ...s,
-                    items: s.items.map((r2, ii) =>
-                      ii !== iIdx
-                        ? r2
-                        : r2.item_type !== 'exercise'
-                          ? r2
-                          : {
-                              ...r2,
-                              exercise_id: row.exercise_id,
-                              exercise_variant_id: row.exercise_variant_id,
-                              exercise_title: row.exercise_title,
-                              variants: row.variants,
-                            }
-                    ),
-                  }
-            ),
+            sections: prev.sections.map((s, si) => {
+              if (si !== sIdx) return s
+              const items = [...(s.items || [])]
+              if (typeof iIdx === 'number') {
+                const cur = items[iIdx]
+                if (!cur || cur.item_type !== 'exercise') return s
+                const [first, ...tail] = rows
+                items[iIdx] = {
+                  ...cur,
+                  exercise_id: first.exercise_id,
+                  exercise_variant_id: first.exercise_variant_id,
+                  exercise_title: first.exercise_title,
+                  variants: first.variants,
+                }
+                if (tail.length) items.splice(iIdx + 1, 0, ...tail)
+                return { ...s, items }
+              }
+              return { ...s, items: [...items, ...rows] }
+            }),
           }))
           setExercisePickerOpen(false)
           setExercisePickerTarget(null)