package engine

import (
	"runtime"
	"testing"
)

func TestSearchDescriptionEmptyAndSlugRequirements(t *testing.T) {
	t.Parallel()

	if diagnostics := validateSearch(Search{}, ""); len(diagnostics) != 0 {
		t.Fatalf("zero search diagnostics = %#v", diagnostics)
	}
	if diagnostics := validateSearch(Searches(), ""); len(diagnostics) != 0 {
		t.Fatalf("empty concatenation diagnostics = %#v", diagnostics)
	}
	if diagnostics := validateSearch(Paths(), ""); len(diagnostics) != 0 {
		t.Fatalf("empty path list diagnostics = %#v", diagnostics)
	}
	if diagnostics := validateSearch(Paths("relative/config.yml"), ""); len(diagnostics) != 0 {
		t.Fatalf("literal path unexpectedly requires a slug: %#v", diagnostics)
	}
	generic := SearchDirectory("configs", DirectorySearchOptions{Filenames: []FilenameGroup{GenericFilenames()}})
	if diagnostics := validateSearch(generic, ""); len(diagnostics) != 0 {
		t.Fatalf("generic-only directory unexpectedly requires a slug: %#v", diagnostics)
	}
	if diagnostics := validateSearch(SearchDirectory("configs"), ""); len(diagnostics) == 0 || diagnostics[0].Code != CodeOptionsInvalid {
		t.Fatalf("default named directory accepted an empty slug: %#v", diagnostics)
	}
	if diagnostics := validateSearch(UnixSystemDirectories(), "myapp"); len(diagnostics) != 0 {
		t.Fatalf("valid preset slug diagnostics = %#v", diagnostics)
	}
}

func TestSearchDescriptionSnapshotsInputs(t *testing.T) {
	t.Parallel()

	paths := []string{"first.yml", "second.yml"}
	pathSearch := Paths(paths...)
	paths[0] = "changed.yml"

	customNames := []string{"one.yml", "two.yml"}
	group := CustomFilenames(customNames...)
	customNames[0] = "changed.yml"
	groups := []FilenameGroup{group}
	options := DirectorySearchOptions{Filenames: groups}
	directorySearch := SearchDirectory("configs", options)
	groups[0] = GenericFilenames()
	options.Filenames[0] = NamedFilenames()

	searches := []Search{pathSearch, directorySearch}
	combined := Searches(searches...)
	searches[0] = Search{}

	if got := combined.entries[0].path; got != "first.yml" {
		t.Fatalf("snapshotted path = %q", got)
	}
	gotNames := combined.entries[2].filenames[0].names
	if len(gotNames) != 2 || gotNames[0] != "one.yml" || gotNames[1] != "two.yml" {
		t.Fatalf("snapshotted custom names = %#v", gotNames)
	}
	if diagnostics := validateSearch(combined, ""); len(diagnostics) != 0 {
		t.Fatalf("snapshot description diagnostics = %#v", diagnostics)
	}
}

func TestDirectoryFilenameDefaultsAndExplicitEmpty(t *testing.T) {
	t.Parallel()

	omitted := SearchDirectory("configs")
	if len(omitted.entries) != 1 || len(omitted.entries[0].filenames) != 2 || omitted.entries[0].filenames[0].kind != filenameGroupNamed || omitted.entries[0].filenames[1].kind != filenameGroupGeneric {
		t.Fatalf("omitted groups = %#v", omitted.entries)
	}
	explicitNil := SearchDirectory("configs", DirectorySearchOptions{})
	if len(explicitNil.entries[0].filenames) != 2 {
		t.Fatalf("nil filename selection did not use defaults: %#v", explicitNil.entries[0].filenames)
	}
	explicitEmpty := SearchDirectory("configs", DirectorySearchOptions{Filenames: []FilenameGroup{}})
	if explicitEmpty.entries[0].filenames == nil || len(explicitEmpty.entries[0].filenames) != 0 {
		t.Fatalf("explicit empty selection lost its distinction: %#v", explicitEmpty.entries[0].filenames)
	}
	if len(validateSearch(explicitEmpty, "")) != 0 {
		t.Fatal("explicit empty filename selection should need no slug")
	}
}

func TestSearchDescriptionArityAndErrorConcatenation(t *testing.T) {
	t.Parallel()

	tooMany := SearchDirectory("configs", DirectorySearchOptions{}, DirectorySearchOptions{})
	if diagnostics := validateSearch(tooMany, "app"); len(diagnostics) == 0 {
		t.Fatal("multiple option values should be invalid")
	}
	invalid := Paths("")
	combined := Searches(Paths("good.yml"), invalid)
	if diagnostics := validateSearch(combined, ""); len(diagnostics) == 0 {
		t.Fatal("concatenation lost a constructor error")
	}
	if diagnostics := validateSearch(Paths("good.yml", ""), ""); len(diagnostics) == 0 {
		t.Fatal("later invalid path was hidden by an earlier component")
	}
}

func TestSearchDescriptionPreservesFilenameGroupOrder(t *testing.T) {
	t.Parallel()

	groups := []FilenameGroup{GenericFilenames(), NamedFilenames(), CustomFilenames("override.yml")}
	search := SearchDirectory("configs", DirectorySearchOptions{Filenames: groups})
	got := search.entries[0].filenames
	if len(got) != 3 || got[0].kind != filenameGroupGeneric || got[1].kind != filenameGroupNamed || got[2].names[0] != "override.yml" {
		t.Fatalf("filename group order = %#v", got)
	}
	if got := SearchDirectory("configs", DirectorySearchOptions{Filenames: []FilenameGroup{CustomFilenames()}}).entries[0].filenames[0].names; len(got) != 0 {
		t.Fatalf("empty custom group = %#v", got)
	}
}

func TestFilenameComponentValidation(t *testing.T) {
	t.Parallel()

	for _, value := range []string{"", ".", "..", "nested/name", "bad\x00name"} {
		if validFilenameComponent(value) {
			t.Errorf("validFilenameComponent(%q) = true", value)
		}
	}
	if runtime.GOOS == "windows" {
		for _, value := range []string{"CON", "nul.txt", "name.", "bad:name"} {
			if validFilenameComponent(value) {
				t.Errorf("Windows component %q unexpectedly accepted", value)
			}
		}
	} else {
		for _, value := range []string{"name with spaces", "naïve"} {
			if !validFilenameComponent(value) {
				t.Errorf("host-valid component %q rejected", value)
			}
		}
	}
	if diagnostics := validateSearch(SearchDirectory("configs", DirectorySearchOptions{Filenames: []FilenameGroup{CustomFilenames("bad/name")}}), ""); len(diagnostics) == 0 {
		t.Fatal("invalid custom filename was not retained for validation")
	}
	for _, value := range []string{"CON", "nul.txt", "COM¹.log", "LPT³.txt", "name.", "bad:name", "bad\x01name"} {
		if validWindowsFilenameComponent(value) {
			t.Errorf("Windows component %q unexpectedly accepted", value)
		}
	}
	for _, value := range []string{"name with spaces", "naïve"} {
		if !validWindowsFilenameComponent(value) {
			t.Errorf("valid Windows component %q rejected", value)
		}
	}
}