package game

import (
	"io"
	"testing"

	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
	"github.com/muesli/termenv"
)

func TestColorAndCharSwitching(t *testing.T) {
	c := NewCanvas()
	m := NewModel(c, "test-id", "tester", newTestRenderer())
	c.Join("test-id", "tester", nil)

	// First keypress just exits the intro screen, per Update()'s own logic.
	mi, _ := m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("3")})
	m = mi.(Model)
	if m.state != stateCanvas {
		t.Fatalf("expected first keypress to exit intro, state=%v", m.state)
	}
	if m.inkColorIdx != 0 {
		t.Fatalf("expected inkColorIdx unchanged by the intro-exit keypress, got %d", m.inkColorIdx)
	}

	// Now actually press "3" for color selection.
	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("3")})
	m = mi.(Model)
	if m.inkColorIdx != 2 {
		t.Fatalf("expected inkColorIdx=2 after pressing '3', got %d", m.inkColorIdx)
	}

	// Paint with the selected color.
	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeySpace})
	m = mi.(Model)

	cells, cursors := c.Snapshot()
	cur := cursors["test-id"]
	painted := cells[cur.Y][cur.X]
	if painted.Char != charPalette[0] {
		t.Fatalf("expected painted char to be default charPalette[0]=%q, got %q", charPalette[0], painted.Char)
	}
	if painted.Color != inkPalette[2] {
		t.Fatalf("expected painted color to be inkPalette[2]=%q (selected via '3'), got %q", inkPalette[2], painted.Color)
	}
}

func TestCharCycling(t *testing.T) {
	c := NewCanvas()
	m := NewModel(c, "test-id", "tester", newTestRenderer())
	c.Join("test-id", "tester", nil)

	mi, _ := m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("x")}) // exit intro
	m = mi.(Model)

	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("]")})
	m = mi.(Model)
	if m.charIdx != 1 {
		t.Fatalf("expected charIdx=1 after ']', got %d", m.charIdx)
	}
}

func TestViewChangesAfterMoveAwayFromPaint(t *testing.T) {
	c := NewCanvas()
	m := NewModel(c, "test-id", "tester", newTestRenderer())
	c.Join("test-id", "tester", nil)

	mi, _ := m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("x")}) // exit intro
	m = mi.(Model)
	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeySpace}) // paint
	m = mi.(Model)

	viewAtPaintPosition := m.View()

	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("l")}) // move right
	m = mi.(Model)

	viewAfterMove := m.View()

	if viewAtPaintPosition == viewAfterMove {
		t.Fatal("expected View() output to differ after moving away from a painted cell, but it's identical")
	}
	t.Logf("view at paint position:\n%s", viewAtPaintPosition)
	t.Logf("view after move:\n%s", viewAfterMove)
}

func TestMoveCursorActuallyMoves(t *testing.T) {
	c := NewCanvas()
	m := NewModel(c, "test-id", "tester", newTestRenderer())
	c.Join("test-id", "tester", nil)

	before := c.CursorsSnapshot()["test-id"]
	t.Logf("before: x=%d y=%d", before.X, before.Y)

	mi, _ := m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("x")}) // exit intro
	m = mi.(Model)
	mi, _ = m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("l")}) // move right
	m = mi.(Model)

	after := c.CursorsSnapshot()["test-id"]
	t.Logf("after: x=%d y=%d", after.X, after.Y)

	if after.X != before.X+1 {
		t.Fatalf("expected cursor X to move from %d to %d, got %d", before.X, before.X+1, after.X)
	}
}

// newTestRenderer forces TrueColor rather than letting lipgloss
// auto-detect from the writer (io.Discard, like any non-*os.File writer,
// would otherwise be treated as non-color-capable) -- matches main.go's
// real per-session renderer setup, so these tests actually exercise the
// same styling path a real SSH session does instead of silently testing
// an unstyled/plain-text code path that would mask exactly this class
// of bug.
func newTestRenderer() *lipgloss.Renderer {
	r := lipgloss.NewRenderer(io.Discard)
	r.SetColorProfile(termenv.TrueColor)
	return r
}