feat(nav): begin implementing reworking of universal filter sampling …

…with controller (#373)

xfs/nav/sampling-adapters.go

@@ -52,7 +52,7 @@ func createSamplingAdapters() samplingAdaptersCollection {
 			contents.Files = fn(contents.Files, int(noOf.Files))
 		},
 		filterWithIt: func(contents *DirectoryContents, iterator *directoryEntryWhileIt) {
-			panic("🔥 FilterWithIt func for SubscribeFiles NOT-IMPLEMENTED")
+			contents.Files = iterator.sampleOf(contents.Files)
 		},
 		isFull: func(filtered []fs.DirEntry, noOf *SampleNoOf) bool {
 			return len(filtered) == int(noOf.Files)

xfs/nav/sampling-iteration.go

@@ -15,6 +15,10 @@ type WhileDirectoryPredicate func(iterator collections.IteratorCtrl[fs.DirEntry]
 // EachDirectoryItemPredicate callback to invoke for each child item
 type EachDirectoryItemPredicate func(childItem *TraverseItem) bool
 
+type filteredInfo struct {
+	counts SampleNoOf
+}
+
 // directoryEntryWhileIt
 type directoryEntryWhileIt struct {
 	forward   bool
@@ -121,6 +125,8 @@ func (i *directoryEntryWhileIt) sample() []fs.DirEntry {
 	parent := i.tp.current
 
 	for entry := i.iterator.Start(); i.while(i.iterator, &result); entry = i.iterator.Next() {
+		var fi filteredInfo
+
 		info, err := entry.Info()
 		path := filepath.Join(parent.Path, entry.Name())
 		child := &TraverseItem{
@@ -145,6 +151,12 @@ func (i *directoryEntryWhileIt) sample() []fs.DirEntry {
 		if i.each(child) {
 			result = append(result, entry)
 
+			if info.IsDir() {
+				fi.counts.Folders++
+			} else {
+				fi.counts.Files++
+			}
+
 			child.markFiltered()
 		}
 	}

xfs/nav/traverse-sample_test.go

@@ -173,6 +173,29 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 		}),
 
+		// >>> universal filter
+		XEntry(nil, &sampleTE{
+			naviTE: naviTE{
+				message:      "universal: first by filter, first single files",
+				should:       "invoke for at most single file per directory",
+				subscription: nav.SubscribeAny,
+				prohibited:   []string{"cover.night-drive"},
+			},
+			filter: &filterTE{
+				name:    "items with .flac suffix",
+				pattern: "*.flac",
+				scope:   nav.ScopeLeafEn,
+			},
+			sampleType: nav.SampleTypeFilterEn,
+			noOf: nav.SampleNoOf{
+				Files: 1,
+			},
+			expectedNoOf: directoryQuantities{
+				files: 4,
+			},
+		}),
+		// <<<
+
 		Entry(nil, &sampleTE{
 			naviTE: naviTE{
 				message:      "filtered folders: first by filter, with 2 folders that start with A",
@@ -218,7 +241,7 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 		}),
 
-		XEntry(nil, &sampleTE{
+		Entry(nil, &sampleTE{
 			naviTE: naviTE{
 				message:      "folders with files: first by slice, with 2 folders",
 				should:       "invoke for at most 2 folders per directory",
@@ -234,7 +257,7 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 		}),
 
-		XEntry(nil, &sampleTE{
+		Entry(nil, &sampleTE{
 			naviTE: naviTE{
 				message:      "folders with files: last by slice, with last single folder",
 				should:       "invoke for only last folder per directory",
@@ -243,7 +266,6 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 			sampleType: nav.SampleTypeSliceEn,
 			reverse:    true,
-			// getSamplerFn: nav.GetLastUsingSliceSampler,
 			noOf: nav.SampleNoOf{
 				Folders: 1,
 			},
@@ -285,7 +307,7 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 		}),
 
-		XEntry(nil, &sampleTE{ // ✨✨✨
+		Entry(nil, &sampleTE{ // ✨✨✨
 			naviTE: naviTE{
 				message:      "filtered files: first by filter, 2 files",
 				should:       "invoke for at most 2 files per directory",
@@ -299,7 +321,6 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 				scope:   nav.ScopeLeafEn,
 			},
 			sampleType: nav.SampleTypeFilterEn,
-			// getSamplerFn: nav.GetFirstUsingFilterSampler,
 			noOf: nav.SampleNoOf{
 				Files: 2,
 			},
@@ -308,7 +329,7 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 		}),
 
-		XEntry(nil, &sampleTE{
+		Entry(nil, &sampleTE{
 			naviTE: naviTE{
 				message:      "filtered files: last by filter, last 2 files",
 				should:       "invoke for at most 2 files per directory",
@@ -323,7 +344,6 @@ var _ = Describe("Traverse With Sample", Ordered, func() {
 			},
 			sampleType: nav.SampleTypeFilterEn,
 			reverse:    true,
-			// getSamplerFn: nav.GetLastUsingFilterSampler,
 			noOf: nav.SampleNoOf{
 				Files: 2,
 			},