package ui

import (
	"strings"
	"testing"

	"github.com/gdamore/tcell/v2"
	"github.com/rivo/tview"
)

func rowText(screen tcell.SimulationScreen, y, x0, x1 int) string {
	var b strings.Builder
	for x := x0; x < x1; x++ {
		ch, _, _, _ := screen.GetContent(x, y)
		b.WriteRune(ch)
	}
	return b.String()
}

func TestFlowWrap(t *testing.T) {
	text := "one two three four five six seven eight nine ten"
	// Narrow (10) for the first two lines, wide (25) afterwards.
	got := flowWrap(text, 10, 25, 2)
	want := []string{"one two", "three four", "five six seven eight nine", "ten"}
	if strings.Join(got, "|") != strings.Join(want, "|") {
		t.Errorf("got %q, want %q", got, want)
	}
	// Without a poster everything is wide.
	if got := flowWrap(text, 10, 25, 0); got[0] != "one two three four five" {
		t.Errorf("no poster: %q", got)
	}
	// Newlines are kept, blank lines too; trailing blank lines are dropped.
	got = flowWrap("head\nfacts\n\nplot words\n", 20, 20, 0)
	if strings.Join(got, "|") != "head|facts||plot words" {
		t.Errorf("newlines: %q", got)
	}
	// Color tags have no width and escaped brackets count as one character.
	got = flowWrap("[red]ab[-] cd ef", 5, 5, 0)
	if strings.Join(got, "|") != "[red]ab[-] cd|ef" {
		t.Errorf("tags: %q", got)
	}
	if got := flowWrap(tview.Escape("[1080p]")+" x", 9, 9, 0); len(got) != 1 {
		t.Errorf("escaped brackets: %q", got)
	}
	// A word wider than the column is not split or lost.
	if got := flowWrap("a verylongwordhere b", 5, 5, 0); strings.Join(got, "|") != "a|verylongwordhere|b" {
		t.Errorf("long word: %q", got)
	}
}

func TestDetailPaneFlowsAroundPoster(t *testing.T) {
	a := newTestApp(t)
	screen := tcell.NewSimulationScreen("")
	if err := screen.Init(); err != nil {
		t.Fatal(err)
	}
	defer screen.Fini()
	screen.SetSize(60, 40)

	plot := strings.Repeat("plot ", 220) // long enough to run past the poster
	d := newDetailPane(a)
	d.SetRect(0, 0, 60, 40)
	d.Show(detailText{head: "[::b]The Matrix (1999)[::-]\nStatus: released\n", plot: plot}, coverRef{})

	// Without a poster the text uses the full width from the top.
	d.Draw(screen)
	if got := rowText(screen, 1, 1, 30); !strings.HasPrefix(got, "The Matrix (1999)") {
		t.Errorf("first line = %q", got)
	}
	if got := strings.TrimSpace(rowText(screen, 5, 1, 59)); len(got) < 50 {
		t.Errorf("without a poster the text should use the full width: %q", got)
	}

	// With a poster (23×17 cells at the top right) the text runs beside it.
	d.hasCover = true
	d.cover.setImage(stripes(40, 60))
	d.Draw(screen)
	if d.coverW != 23 || d.coverH != 17 {
		t.Fatalf("poster size %dx%d, want 23x17", d.coverW, d.coverH)
	}
	if got := rowText(screen, 1, 1, 30); !strings.HasPrefix(got, "The Matrix (1999)") {
		t.Errorf("head moved: %q", got)
	}
	if got := rowText(screen, 4, 1, 30); !strings.HasPrefix(got, "plot plot") {
		t.Errorf("the plot starts beside the poster, right after the head: %q", got)
	}
	// Beside the poster the text stays left of it with a gap of two columns
	// (58-23-2 = 33 columns), and the row right under the poster is kept clear too.
	for y := 1; y <= d.coverH+coverGapRows; y++ {
		if got := strings.TrimRight(rowText(screen, y, 1, 36), " "); len([]rune(got)) > 33 {
			t.Errorf("row %d runs into the poster's margin: %q", y, got)
		}
	}
	// Further down it uses the full width.
	if got := strings.TrimSpace(rowText(screen, d.coverH+3, 1, 59)); len(got) < 50 {
		t.Errorf("below the poster the text should use the full width: %q", got)
	}
	// The poster sits against the right edge of the pane.
	if ch, _, st, _ := screen.GetContent(58, 1); ch == ' ' && st == tcell.StyleDefault {
		t.Error("nothing drawn at the poster's right edge")
	}

	// A pane too short for the poster falls back to plain text.
	d.SetRect(0, 0, 60, 10)
	d.Draw(screen)
	if d.coverW != 0 {
		t.Error("a short pane must drop the poster")
	}
}