package e2e_test

import (
	"testing"
	"time"

	"pad/internal/editor"
	"pad/internal/test/e2e"
	"pad/internal/ui"
)

func TestEditorClickToMoveCursorWithScroll(t *testing.T) {
	h := e2e.NewHarnessWithDefaults()
	h.Run() // Start the harness!
	defer h.Cleanup()

	// Switch to editor page
	editor.GoToEditor(nil)
	h.SendConfig(780, 1688)
	// Give it a moment to initialize
	time.Sleep(200 * time.Millisecond)

	// Wait for frame
	_, err := h.WaitForFrameCount(1, 5*time.Second)
	if err != nil {
		t.Fatalf("timeout waiting for frame: %v", err)
	}

	// Setup:
	// - 2 lines, each 10 chars + newline.
	// - Line height = 14 * 1.2 = 16.8 (rounded?) Let's check EditorLineHeight()
	// EditorLineHeight is 14 * 1.2 = 16.8.
	lineHeight := 16.8
	editor.TheState.Editor.Buffer = "Line 1\nLine 2\nLine 3"
	
	// Scroll to start of Line 2 (skip Line 1)
	editor.TheState.ScrollOffset = ui.Dp(lineHeight)

	// GlyphLayout:
	// Line 1: y = 0
	// Line 2: y = 16.8
	// Line 3: y = 33.6
	editor.TheState.Editor.GlyphLayout = ui.GlyphLayout{
		ByteOffsets: []int{0, 7, 14}, // Start of each line
		X:           []ui.Dp{10, 10, 10},
		Y:           []ui.Dp{ui.Dp(0), ui.Dp(lineHeight), ui.Dp(lineHeight * 2)},
		Advance:     []ui.Dp{10, 10, 10},
	}

	// Tap at y=10 (within the text area).
	// Because of scroll=16.8, this should correspond to:
	// visualLine = (y + scroll) / lineHeight = (10 + 16.8) / 16.8 = 26.8 / 16.8 = 1.59 -> 1
	// Line 1 is index 0. Line 2 is index 1.
	// So visualLine 1 should be Line 2.
	
	// The problem is that SetCursorFromPoint expects y in DP, but receives it as raw pixels
	// if we're not careful. Let's pass the y value properly.
	// The test harness sends raw pixel coordinates to handler.
	// EditorLayout converts tap point:
	// localY := float64(pt.Y - editorRegion.Y + TheState.ScrollOffset)
	// So the handler receives Y as pt.Y, where pt.Y is relative to the screen.
	// The test harness doesn't seem to account for region offset.
	
	// Let's debug by printing in the test.
	t.Logf("ScrollOffset: %v", editor.TheState.ScrollOffset)
	
	h.SendInput([]ui.InputEvent{
		{
			Handler: func(data any) {
				if pt, ok := data.(ui.Point); ok {
					// Manually simulate the offset correction that EditorLayout does
					// editorRegion.Y is margin(10) + statusBarH(52) = 62.
					// Let's set pt.Y to 10 + 62 = 72.
					localY := float64(pt.Y) - 62.0 + float64(editor.TheState.ScrollOffset)
					editor.SetCursorFromPoint(float64(pt.X), localY)
				}
			},
			Data: ui.Point{X: 10, Y: 72},
		},
	})

	// Assert cursor moved to start of Line 2 (offset 7)
	time.Sleep(100 * time.Millisecond) // Give logic goroutine a moment to process input
	t.Logf("Cursor position: %d", editor.TheState.Editor.CursorPosition)
	if editor.TheState.Editor.CursorPosition != 7 {
		t.Errorf("expected cursor to move to 7 (Line 2), but got %d", editor.TheState.Editor.CursorPosition)
	}
}