package ui

import (
	"strings"
	"testing"
)

// spotifyRowDump is the shape of a real Spotify search-results screen, trimmed
// to the rows that matter. The first row is a search *suggestion* (one line of
// text); the rest are result rows (title + subtitle).
const spotifyRowDump = `<?xml version='1.0' encoding='UTF-8' standalone='yes' ?>
<hierarchy rotation="0">
  <node index="0" class="androidx.recyclerview.widget.RecyclerView" resource-id="com.spotify.music:id/search_content_recyclerview" clickable="false" enabled="true" bounds="[0,251][1080,2400]">
    <node index="0" class="android.view.ViewGroup" resource-id="com.spotify.music:id/row_root" clickable="true" enabled="true" bounds="[0,251][1080,425]">
      <node index="0" class="android.widget.ImageView" resource-id="com.spotify.music:id/icon_view" clickable="false" enabled="true" bounds="[42,296][126,380]"/>
      <node index="1" class="android.widget.TextView" resource-id="com.spotify.music:id/query" text="rolling stones honky tonk women single" clickable="false" enabled="true" bounds="[158,272][954,404]"/>
      <node index="2" class="android.widget.ImageView" resource-id="com.spotify.music:id/tap_ahead_button" content-desc="Add suggestion “rolling stones honky tonk women single”" clickable="true" enabled="true" bounds="[954,296][1080,380]"/>
    </node>
    <node index="1" class="android.view.ViewGroup" resource-id="com.spotify.music:id/row_root" clickable="true" enabled="true" bounds="[0,794][1080,962]">
      <node index="0" class="android.widget.ImageView" resource-id="com.spotify.music:id/artwork" clickable="false" enabled="true" bounds="[42,815][168,941]"/>
      <node index="1" class="android.view.ViewGroup" resource-id="com.spotify.music:id/play_indicator" clickable="false" enabled="true" bounds="[200,832][232,864]">
        <node index="0" class="android.view.View" content-desc="Paused" clickable="false" enabled="true" bounds="[200,832][232,864]"/>
      </node>
      <node index="2" class="android.widget.TextView" resource-id="com.spotify.music:id/title" text="Honky Tonk Women" clickable="false" enabled="true" bounds="[243,815][828,881]"/>
      <node index="3" class="android.widget.TextView" resource-id="com.spotify.music:id/subtitle" text="Song • The Rolling Stones" clickable="false" enabled="true" bounds="[200,886][828,941]"/>
      <node index="4" class="android.view.ViewGroup" resource-id="com.spotify.music:id/action_bar" clickable="false" enabled="true" bounds="[828,815][1080,941]">
        <node index="0" class="android.widget.ImageButton" resource-id="com.spotify.music:id/context_menu_button" content-desc="More options for song Honky Tonk Women" clickable="true" enabled="true" bounds="[828,815][954,941]"/>
        <node index="1" class="android.widget.Button" resource-id="com.spotify.music:id/add_button" content-desc="Add Honky Tonk Women to My Library" clickable="true" enabled="true" bounds="[954,815][1080,941]"/>
      </node>
    </node>
    <node index="2" class="android.view.ViewGroup" resource-id="com.spotify.music:id/row_root" clickable="true" enabled="true" bounds="[0,962][1080,1130]">
      <node index="0" class="android.widget.TextView" resource-id="com.spotify.music:id/title" text="Honky Tonk Women - Mono Version" clickable="false" enabled="true" bounds="[200,983][828,1049]"/>
      <node index="1" class="android.widget.TextView" resource-id="com.spotify.music:id/subtitle" text="Song • The Rolling Stones" clickable="false" enabled="true" bounds="[200,1054][828,1109]"/>
    </node>
    <node index="3" class="android.view.ViewGroup" resource-id="com.spotify.music:id/row_root" clickable="true" enabled="true" bounds="[0,1130][1080,1359]">
      <node index="0" class="android.widget.TextView" resource-id="com.spotify.music:id/title" text="Honky Tonk Woman (The Rolling Stones) Covers" clickable="false" enabled="true" bounds="[200,1151][954,1283]"/>
      <node index="1" class="android.widget.TextView" resource-id="com.spotify.music:id/subtitle" text="Playlist" clickable="false" enabled="true" bounds="[200,1283][954,1338]"/>
    </node>
    <node index="4" class="android.view.ViewGroup" resource-id="com.spotify.music:id/row_root" clickable="true" enabled="true" bounds="[0,2367][1080,2400]">
      <node index="0" class="android.widget.TextView" resource-id="com.spotify.music:id/title" text="Honky Tonk Women - Live" clickable="false" enabled="true" bounds="[200,2388][828,2400]"/>
      <node index="1" class="android.widget.TextView" resource-id="com.spotify.music:id/subtitle" text="Song • The Rolling Stones" clickable="false" enabled="true" bounds="[200,2388][828,2400]"/>
    </node>
  </node>
</hierarchy>`

const spotifyRowID = "com.spotify.music:id/row_root"

func spotifyRows(t *testing.T) *Hierarchy {
	t.Helper()
	h, err := parseHierarchy([]byte(spotifyRowDump))
	if err != nil {
		t.Fatalf("parseHierarchy: %v", err)
	}
	return h
}

func TestBestRowPicksTheTopResultOfARealScreen(t *testing.T) {
	h := spotifyRows(t)
	row, err := h.BestRow("Rolling Stones Honky Tonk", spotifyRowID, 1080, 2400)
	if err != nil {
		t.Fatalf("BestRow: %v", err)
	}
	if row.Title != "Honky Tonk Women" {
		t.Fatalf("chose row %q, want the canonical top hit; rows: %v", row.Title, row.Texts)
	}
	// The tap must land on the row, on the title, not on a row button.
	if row.Centre.X < 200 || row.Centre.X > 828 {
		t.Fatalf("tap x=%d is outside the title", row.Centre.X)
	}
	if row.Centre.Y < 794 || row.Centre.Y > 962 {
		t.Fatalf("tap y=%d is outside the row", row.Centre.Y)
	}
}

func TestBestRowIgnoresSearchSuggestions(t *testing.T) {
	h := spotifyRows(t)
	// The suggestion row carries every query word, but it is a single line of
	// text, so it is not a result row.
	query := "rolling stones honky tonk women single"
	row, err := h.BestRow(query, spotifyRowID, 1080, 2400)
	if err != nil {
		t.Fatalf("BestRow: %v", err)
	}
	if row.Title == "rolling stones honky tonk women single" {
		t.Fatal("chose the search suggestion; a suggestion has no subtitle and is not a result")
	}
}

func TestBestRowIgnoresRowsClippedByTheScreenEdge(t *testing.T) {
	// The last row is cut off at the bottom of the list: only 33 pixels tall,
	// with its centre underneath the navigation area. It matches the query
	// better than any other row, and it must still lose, because tapping it
	// would press something the user cannot see.
	h := spotifyRows(t)
	row, err := h.BestRow("Honky Tonk Women Live", spotifyRowID, 1080, 2400)
	if err != nil {
		t.Fatalf("BestRow: %v", err)
	}
	if row.Title == "Honky Tonk Women - Live" {
		t.Fatal("chose a row clipped by the bottom of the list")
	}
}

func TestBestRowRefusesAnUnknownQuery(t *testing.T) {
	h := spotifyRows(t)
	if _, err := h.BestRow("Chopin Nocturne", spotifyRowID, 1080, 2400); err == nil {
		t.Fatal("expected an error when no row matches the query")
	}
}

func TestBestRowWorksWithoutARowID(t *testing.T) {
	h := spotifyRows(t)
	row, err := h.BestRow("The Rolling Stones Honky Tonk Women", "", 1080, 2400)
	if err != nil {
		t.Fatalf("BestRow without a row id: %v", err)
	}
	if row.Title != "Honky Tonk Women" {
		t.Fatalf("chose %q", row.Title)
	}
}

func TestRowScorePrefersPrecision(t *testing.T) {
	exact, _ := rowScore(tokenize("honky tonk women"), []string{"Honky Tonk Women", "Song • The Rolling Stones"})
	noisy, _ := rowScore(tokenize("honky tonk women"), []string{"Honky Tonk Women Live Licks Tour 2009 Remastered Deluxe Edition", "Song • The Rolling Stones, Sheryl Crow"})
	if exact <= noisy {
		t.Fatalf("an exact title (%f) must beat a noisy one (%f)", exact, noisy)
	}
}

// TestBestRowPrefersTheTopHitWhenItsRowCarriesStateText is the regression that
// cost the most: the top hit's row carries a "Paused" state indicator once it is
// the loaded track, and counting that description as row text pushed the score
// below an identical duplicate further down the list. tap_row then pressed the
// duplicate at y=1443 and playback never started.
func TestBestRowPrefersTheTopHitWhenItsRowCarriesStateText(t *testing.T) {
	h := spotifyRows(t)
	row, err := h.BestRow("Rolling Stones Honky Tonk", spotifyRowID, 1080, 2400)
	if err != nil {
		t.Fatalf("BestRow: %v", err)
	}
	if row.Title != "Honky Tonk Women" {
		t.Fatalf("chose %q", row.Title)
	}
	if row.Top != 794 {
		t.Fatalf("chose the row at y=%d, want the top hit at y=794", row.Top)
	}
	if row.Centre.Y != (794+962)/2 {
		t.Fatalf("tap point y=%d is not the top row's centre", row.Centre.Y)
	}
}

func TestRowTextsIgnoreStateDescriptions(t *testing.T) {
	h := spotifyRows(t)
	var top *Node
	h.Walk(func(n *Node) {
		if n.ResourceID == spotifyRowID && n.Bounds == "[0,794][1080,962]" {
			top = n
		}
	})
	if top == nil {
		t.Fatal("top row not found in the sample dump")
	}
	for _, line := range rowTexts(top) {
		if line == "Paused" {
			t.Fatal("the row's state description must not count as row text")
		}
	}
}

func TestRowTextsSkipActionButtons(t *testing.T) {
	h := spotifyRows(t)

	// The suggestion row: one line of text plus an "Add suggestion" button.
	var suggestion *Node
	h.Walk(func(n *Node) {
		if n.ResourceID == spotifyRowID && n.Bounds == "[0,251][1080,425]" {
			suggestion = n
		}
	})
	if suggestion == nil {
		t.Fatal("suggestion row not found in the sample dump")
	}
	texts := rowTexts(suggestion)
	if len(texts) != 1 {
		t.Fatalf("a suggestion row's own text = %v, want 1 line", texts)
	}

	// A result row: title + subtitle, without the row's action buttons.
	var result *Node
	h.Walk(func(n *Node) {
		if n.ResourceID == spotifyRowID && n.Bounds == "[0,794][1080,962]" {
			result = n
		}
	})
	texts = rowTexts(result)
	if len(texts) != 2 || texts[0] != "Honky Tonk Women" || texts[1] != "Song • The Rolling Stones" {
		t.Fatalf("a result row's own text = %v", texts)
	}
	for _, bad := range texts {
		if strings.Contains(bad, "More options") || strings.Contains(bad, "Add ") {
			t.Fatalf("row text %q came from an action button", bad)
		}
	}
}

func TestTokenize(t *testing.T) {
	got := tokenize("Honky Tonk Women - Mono Version (Remastered)")
	want := []string{"honky", "tonk", "women", "mono", "version", "remastered"}
	if len(got) != len(want) {
		t.Fatalf("tokenize = %v, want %v", got, want)
	}
	for i := range want {
		if got[i] != want[i] {
			t.Fatalf("tokenize = %v, want %v", got, want)
		}
	}
}