package engine

import (
	"fmt"
	"strings"
	"testing"
)

func scanWarnings(t *testing.T, ev *env) []string {
	t.Helper()
	ev.scan()
	p, err := ev.st.Pair(ctx, ev.pair.ID)
	if err != nil {
		t.Fatal(err)
	}
	var out []string
	for _, w := range p.LastScanWarnings {
		if !strings.Contains(w, "ffprobe") {
			out = append(out, w)
		}
	}
	return out
}

// The user's situation: a singles library with far more artists and songs
// than the albums library. Slave-only content must not trigger warnings.
func TestSlaveOnlyContentIsNotALayoutProblem(t *testing.T) {
	ev := setup(t, false)
	for i := 0; i < 40; i++ {
		ev.write(ev.slave, fmt.Sprintf("Singles Artist %02d/Some Single/Song.mp3", i), "s")
	}
	for i := 0; i < 10; i++ {
		rel := fmt.Sprintf("Shared Artist/Album/%02d Track.flac", i)
		ev.write(ev.master, rel, "same")
		ev.write(ev.slave, rel, "same")
	}
	ev.write(ev.master, "Master Only/Album/01 X.flac", "m")
	if w := scanWarnings(t, ev); len(w) != 0 {
		t.Fatalf("slave-only content should not produce warnings, got %q", w)
	}
}

func TestRenamedFoldersAreReported(t *testing.T) {
	ev := setup(t, false)
	ev.write(ev.master, "AC_DC/Back in Black/01 Hells Bells.flac", "a")
	ev.write(ev.slave, "AC-DC/Back in Black/01 Hells Bells.mp3", "b")
	ev.write(ev.master, "The Beatles/Abbey Road/01 Come Together.flac", "a")
	ev.write(ev.slave, "Beatles, The/Abbey Road/01 Come Together.mp3", "b")
	ev.write(ev.master, "Avenged Sevenfold/City of Evil/03 Bat Country.flac", "a")
	ev.write(ev.slave, "Avenged Sevenfold/City Of Evil/03 Bat Country.mp3", "b")
	ev.write(ev.slave, "Beyoncé/Lemonade/Formation.mp3", "b")
	ev.write(ev.master, "Beyonce/Lemonade/Formation.flac", "a")
	w := scanWarnings(t, ev)
	if len(w) != 1 {
		t.Fatalf("want one renamed-folders warning, got %q", w)
	}
	for _, want := range []string{`"AC-DC" (slave) vs "AC_DC" (master)`, `"Avenged Sevenfold/City Of Evil" (slave) vs "Avenged Sevenfold/City of Evil" (master)`, "4 folders", "1 more"} {
		if !strings.Contains(w[0], want) {
			t.Errorf("warning %q should contain %q", w[0], want)
		}
	}
}

// A slave library without album folders is a genuine layout difference.
func TestDifferentLayoutIsReported(t *testing.T) {
	ev := setup(t, false)
	for i := 0; i < 24; i++ {
		ev.write(ev.master, fmt.Sprintf("Band/Album/%02d Song Number %d.flac", i+1, i), "m")
		ev.write(ev.slave, fmt.Sprintf("Band/Song Number %d.mp3", i), "s")
	}
	w := scanWarnings(t, ev)
	if len(w) != 1 || !strings.Contains(w[0], "Of 24 songs found in both libraries, 24 are in a different folder") {
		t.Fatalf("want a different-layout warning, got %q", w)
	}
}

// Singles matched to their album version are intended, not a layout problem.
func TestSinglesMatchedToAlbumsAreNotALayoutProblem(t *testing.T) {
	ev := setup(t, false)
	enableApprox(t, ev)
	for i := 0; i < 24; i++ {
		ev.write(ev.master, fmt.Sprintf("Band/Album/%02d Song Number %d.flac", i+1, i), "m")
		ev.write(ev.slave, fmt.Sprintf("Band/Song Number %d - Single/Song Number %d.mp3", i, i), "s")
	}
	if w := scanWarnings(t, ev); len(w) != 0 {
		t.Fatalf("singles matched to album versions should not warn, got %q", w)
	}
}

func TestFolderKey(t *testing.T) {
	same := [][2]string{{"AC/DC", "AC-DC"}, {"The Beatles", "Beatles, The"}, {"Simon & Garfunkel", "Simon and Garfunkel"},
		{"Beyoncé", "Beyonce"}, {"City Of Evil", "City of Evil"}, {"Sigur Rós", "Sigur Ros"}}
	for _, p := range same {
		if folderKey(p[0]) != folderKey(p[1]) {
			t.Errorf("%q and %q should share a key (%q vs %q)", p[0], p[1], folderKey(p[0]), folderKey(p[1]))
		}
	}
	if folderKey("Theory of a Deadman") == folderKey("ory of a Deadman") {
		t.Error(`"The" must only be stripped as a whole word`)
	}
	if folderKey("Nightmare") == folderKey("Nightmare (Deluxe)") {
		t.Error("different folders must keep different keys")
	}
}