GUI_draft_live.py

import sys
import math
import numpy as np

# For smoothing the path
from scipy.signal import savgol_filter

from PyQt5.QtWidgets import (
    QApplication, QMainWindow, QGraphicsView, QGraphicsScene,
    QGraphicsEllipseItem, QGraphicsPixmapItem, QPushButton,
    QHBoxLayout, QVBoxLayout, QWidget, QFileDialog, QGraphicsTextItem,
    QSlider, QLabel, QCheckBox, QGridLayout, QSizePolicy
)
from PyQt5.QtGui import QPixmap, QPen, QBrush, QColor, QFont, QImage
from PyQt5.QtCore import Qt, QRectF, QSize

# live_wire.py must contain something like:
#   from skimage import exposure
#   from skimage.filters import gaussian
#   def preprocess_image(image, sigma=3, clip_limit=0.01): ...
#   def compute_cost_image(path, user_radius, sigma=3, clip_limit=0.01): ...
from live_wire import compute_cost_image, find_path, preprocess_image


# ------------------------------------------------------------------------
# A pan & zoom QGraphicsView
# ------------------------------------------------------------------------
class PanZoomGraphicsView(QGraphicsView):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.setDragMode(QGraphicsView.NoDrag)  # We'll handle panning manually
        self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse)
        self._panning = False
        self._pan_start = None

        # Let it expand in layouts
        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)

    def wheelEvent(self, event):
        """ Zoom in/out with mouse wheel. """
        zoom_in_factor = 1.25
        zoom_out_factor = 1 / zoom_in_factor
        if event.angleDelta().y() > 0:
            self.scale(zoom_in_factor, zoom_in_factor)
        else:
            self.scale(zoom_out_factor, zoom_out_factor)
        event.accept()

    def mousePressEvent(self, event):
        """ If left button: Start panning (unless overridden). """
        if event.button() == Qt.LeftButton:
            self._panning = True
            self._pan_start = event.pos()
            self.setCursor(Qt.ClosedHandCursor)
        super().mousePressEvent(event)

    def mouseMoveEvent(self, event):
        """ If panning, translate the scene. """
        if self._panning and self._pan_start is not None:
            delta = event.pos() - self._pan_start
            self._pan_start = event.pos()
            self.translate(delta.x(), delta.y())
        super().mouseMoveEvent(event)

    def mouseReleaseEvent(self, event):
        """ End panning. """
        if event.button() == Qt.LeftButton:
            self._panning = False
            self.setCursor(Qt.ArrowCursor)
        super().mouseReleaseEvent(event)


# ------------------------------------------------------------------------
# A specialized PanZoomGraphicsView for the circle editor
# ------------------------------------------------------------------------
class CircleEditorGraphicsView(PanZoomGraphicsView):
    def __init__(self, circle_editor_widget, parent=None):
        super().__init__(parent)
        self._circle_editor_widget = circle_editor_widget

    def mousePressEvent(self, event):
        if event.button() == Qt.LeftButton:
            # Check if user clicked on the circle item
            clicked_item = self.itemAt(event.pos())
            if clicked_item is not None:
                # climb up parent chain
                it = clicked_item
                while it is not None and not hasattr(it, "boundingRect"):
                    it = it.parentItem()

                if isinstance(it, DraggableCircleItem):
                    # Let normal item-dragging occur, no pan
                    return QGraphicsView.mousePressEvent(self, event)
        super().mousePressEvent(event)

    def wheelEvent(self, event):
        """
        If the mouse is hovering over the circle, we adjust the circle's radius
        instead of zooming the image.
        """
        pos_in_widget = event.pos()
        item_under = self.itemAt(pos_in_widget)
        if item_under is not None:
            it = item_under
            while it is not None and not hasattr(it, "boundingRect"):
                it = it.parentItem()

            if isinstance(it, DraggableCircleItem):
                delta = event.angleDelta().y()
                step = 1 if delta > 0 else -1
                old_r = it.radius()
                new_r = max(1, old_r + step)
                it.set_radius(new_r)
                self._circle_editor_widget.update_slider_value(new_r)
                event.accept()
                return

        super().wheelEvent(event)


# ------------------------------------------------------------------------
# Draggable circle item (centered at (x, y) with radius)
# ------------------------------------------------------------------------
class DraggableCircleItem(QGraphicsEllipseItem):
    def __init__(self, x, y, radius=20, color=Qt.red, parent=None):
        super().__init__(0, 0, 2*radius, 2*radius, parent)
        self._r = radius

        pen = QPen(color)
        brush = QBrush(color)
        self.setPen(pen)
        self.setBrush(brush)

        # Enable item-based dragging
        self.setFlags(QGraphicsEllipseItem.ItemIsMovable |
                      QGraphicsEllipseItem.ItemIsSelectable |
                      QGraphicsEllipseItem.ItemSendsScenePositionChanges)

        # Position so that (x, y) is the center
        self.setPos(x - radius, y - radius)

    def set_radius(self, r):
        old_center = self.sceneBoundingRect().center()
        self._r = r
        self.setRect(0, 0, 2*r, 2*r)
        new_center = self.sceneBoundingRect().center()
        diff_x = old_center.x() - new_center.x()
        diff_y = old_center.y() - new_center.y()
        self.moveBy(diff_x, diff_y)

    def radius(self):
        return self._r


# ------------------------------------------------------------------------
# Circle editor widget with slider + done
# ------------------------------------------------------------------------
class CircleEditorWidget(QWidget):
    def __init__(self, pixmap, init_radius=20, done_callback=None, parent=None):
        super().__init__(parent)
        self._pixmap = pixmap
        self._done_callback = done_callback
        self._init_radius = init_radius

        layout = QVBoxLayout(self)
        self.setLayout(layout)

        # Specialized CircleEditorGraphicsView
        self._graphics_view = CircleEditorGraphicsView(circle_editor_widget=self)
        self._scene = QGraphicsScene(self)
        self._graphics_view.setScene(self._scene)
        layout.addWidget(self._graphics_view)

        self._image_item = QGraphicsPixmapItem(self._pixmap)
        self._scene.addItem(self._image_item)

        # Put circle in center
        cx = self._pixmap.width() / 2
        cy = self._pixmap.height() / 2
        self._circle_item = DraggableCircleItem(cx, cy, radius=self._init_radius, color=Qt.red)
        self._scene.addItem(self._circle_item)

        # Fit in view
        self._graphics_view.setSceneRect(QRectF(self._pixmap.rect()))
        self._graphics_view.fitInView(self._image_item, Qt.KeepAspectRatio)

        # Bottom controls
        bottom_layout = QHBoxLayout()
        layout.addLayout(bottom_layout)

        # We'll store the label in an attribute so we can update with the slider value
        self._lbl_size = QLabel(f"size ({self._init_radius})")
        bottom_layout.addWidget(self._lbl_size)

        self._slider = QSlider(Qt.Horizontal)
        self._slider.setRange(1, 200)
        self._slider.setValue(self._init_radius)
        bottom_layout.addWidget(self._slider)

        self._btn_done = QPushButton("Done")
        bottom_layout.addWidget(self._btn_done)

        # Connect signals
        self._slider.valueChanged.connect(self._on_slider_changed)
        self._btn_done.clicked.connect(self._on_done_clicked)

    def _on_slider_changed(self, value):
        self._circle_item.set_radius(value)
        self._lbl_size.setText(f"size ({value})")

    def _on_done_clicked(self):
        final_radius = self._circle_item.radius()
        if self._done_callback is not None:
            self._done_callback(final_radius)

    def update_slider_value(self, new_radius):
        self._slider.blockSignals(True)
        self._slider.setValue(new_radius)
        self._slider.blockSignals(False)
        self._lbl_size.setText(f"size ({new_radius})")

    def sizeHint(self):
        return QSize(800, 600)


# ------------------------------------------------------------------------
# Labeled point item
# ------------------------------------------------------------------------
class LabeledPointItem(QGraphicsEllipseItem):
    def __init__(self, x, y, label="", radius=4, color=Qt.red, removable=True, z_value=0, parent=None):
        super().__init__(0, 0, 2*radius, 2*radius, parent)
        self._x = x
        self._y = y
        self._r = radius
        self._removable = removable

        pen = QPen(color)
        brush = QBrush(color)
        self.setPen(pen)
        self.setBrush(brush)
        self.setZValue(z_value)

        self._text_item = None
        if label:
            self._text_item = QGraphicsTextItem(self)
            self._text_item.setPlainText(label)
            self._text_item.setDefaultTextColor(QColor("black"))
            font = QFont("Arial", 14)
            font.setBold(True)
            self._text_item.setFont(font)
            self._scale_text_to_fit()

        self.set_pos(x, y)

    def _scale_text_to_fit(self):
        if not self._text_item:
            return
        self._text_item.setScale(1.0)
        circle_diam = 2 * self._r
        raw_rect = self._text_item.boundingRect()
        text_w = raw_rect.width()
        text_h = raw_rect.height()
        if text_w > circle_diam or text_h > circle_diam:
            scale_factor = min(circle_diam / text_w, circle_diam / text_h)
            self._text_item.setScale(scale_factor)
        self._center_label()

    def _center_label(self):
        if not self._text_item:
            return
        ellipse_w = 2 * self._r
        ellipse_h = 2 * self._r
        raw_rect = self._text_item.boundingRect()
        scale_factor = self._text_item.scale()
        scaled_w = raw_rect.width() * scale_factor
        scaled_h = raw_rect.height() * scale_factor
        tx = (ellipse_w - scaled_w) * 0.5
        ty = (ellipse_h - scaled_h) * 0.5
        self._text_item.setPos(tx, ty)

    def set_pos(self, x, y):
        """Positions the circle so its center is at (x, y)."""
        self._x = x
        self._y = y
        self.setPos(x - self._r, y - self._r)

    def get_pos(self):
        return (self._x, self._y)

    def distance_to(self, x_other, y_other):
        return math.sqrt((self._x - x_other)**2 + (self._y - y_other)**2)

    def is_removable(self):
        return self._removable


# ------------------------------------------------------------------------
# The original ImageGraphicsView with pan & zoom
# ------------------------------------------------------------------------
class ImageGraphicsView(PanZoomGraphicsView):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.scene = QGraphicsScene(self)
        self.setScene(self.scene)

        # Image display
        self.image_item = QGraphicsPixmapItem()
        self.scene.addItem(self.image_item)

        self.anchor_points = []    # List[(x, y)]
        self.point_items = []      # LabeledPointItem
        self.full_path_points = [] # QGraphicsEllipseItems for path
        self._full_path_xy = []    # entire path coords (smoothed)

        self.dot_radius = 4
        self.path_radius = 1
        self.radius_cost_image = 2
        self._img_w = 0
        self._img_h = 0

        self._mouse_pressed = False
        self._press_view_pos = None
        self._drag_threshold = 5
        self._was_dragging = False
        self._dragging_idx = None
        self._drag_offset = (0, 0)
        self._drag_counter = 0

        # Cost images
        self.cost_image_original = None
        self.cost_image = None

        # Rainbow toggle => start with OFF
        self._rainbow_enabled = False

        # Smoothing parameters
        self._savgol_window_length = 7
        self._savgol_polyorder = 1

    def set_rainbow_enabled(self, enabled: bool):
        self._rainbow_enabled = enabled
        self._rebuild_full_path()

    def toggle_rainbow(self):
        self._rainbow_enabled = not self._rainbow_enabled
        self._rebuild_full_path()

    def set_savgol_window_length(self, wlen: int):
        if wlen < 3:
            wlen = 3
        if wlen % 2 == 0:
            wlen += 1
        self._savgol_window_length = wlen

        p = round(wlen / 7.0)
        p = max(1, p)
        if p >= wlen:
            p = wlen - 1
        self._savgol_polyorder = p

        self._rebuild_full_path()

    # --------------------------------------------------------------------
    # LOADING
    # --------------------------------------------------------------------
    def load_image(self, path):
        pixmap = QPixmap(path)
        if not pixmap.isNull():
            self.image_item.setPixmap(pixmap)
            self.setSceneRect(QRectF(pixmap.rect()))

            self._img_w = pixmap.width()
            self._img_h = pixmap.height()

            self._clear_all_points()
            self.resetTransform()
            self.fitInView(self.image_item, Qt.KeepAspectRatio)

            # By default, add S/E
            s_x, s_y = 0.15 * self._img_w, 0.5 * self._img_h
            e_x, e_y = 0.85 * self._img_w, 0.5 * self._img_h
            self._insert_anchor_point(-1, s_x, s_y, label="S", removable=False, z_val=100, radius=6)
            self._insert_anchor_point(-1, e_x, e_y, label="E", removable=False, z_val=100, radius=6)

    # --------------------------------------------------------------------
    # ANCHOR POINTS
    # --------------------------------------------------------------------
    def _insert_anchor_point(self, idx, x, y, label="", removable=True, z_val=0, radius=4):
        x_clamped = self._clamp(x, radius, self._img_w - radius)
        y_clamped = self._clamp(y, radius, self._img_h - radius)

        if idx < 0:
            # Insert before E if there's at least 2 anchors
            if len(self.anchor_points) >= 2:
                idx = len(self.anchor_points) - 1
            else:
                idx = len(self.anchor_points)

        self.anchor_points.insert(idx, (x_clamped, y_clamped))
        color = Qt.green if label in ("S", "E") else Qt.red
        item = LabeledPointItem(x_clamped, y_clamped,
                                label=label, radius=radius, color=color,
                                removable=removable, z_value=z_val)
        self.point_items.insert(idx, item)
        self.scene.addItem(item)

    def _add_guide_point(self, x, y):
        # Ensure we clamp properly
        x_clamped = self._clamp(x, self.dot_radius, self._img_w - self.dot_radius)
        y_clamped = self._clamp(y, self.dot_radius, self._img_h - self.dot_radius)

        self._revert_cost_to_original()

        if not self._full_path_xy:
            self._insert_anchor_point(-1, x_clamped, y_clamped,
                                      label="", removable=True, z_val=1, radius=self.dot_radius)
        else:
            self._insert_anchor_between_subpath(x_clamped, y_clamped)

        self._apply_all_guide_points_to_cost()
        self._rebuild_full_path()

    def _insert_anchor_between_subpath(self, x_new, y_new):
        # If somehow we have no path yet
        if not self._full_path_xy:
            self._insert_anchor_point(-1, x_new, y_new)
            return

        # Find nearest point in the current full path
        best_idx = None
        best_d2 = float('inf')
        for i, (px, py) in enumerate(self._full_path_xy):
            dx = px - x_new
            dy = py - y_new
            d2 = dx*dx + dy*dy
            if d2 < best_d2:
                best_d2 = d2
                best_idx = i

        if best_idx is None:
            self._insert_anchor_point(-1, x_new, y_new)
            return

        def approx_equal(xa, ya, xb, yb, tol=1e-3):
            return (abs(xa - xb) < tol) and (abs(ya - yb) < tol)

        def is_anchor(coord):
            cx, cy = coord
            for (ax, ay) in self.anchor_points:
                if approx_equal(ax, ay, cx, cy):
                    return True
            return False

        # Walk left
        left_anchor_pt = None
        iL = best_idx
        while iL >= 0:
            px, py = self._full_path_xy[iL]
            if is_anchor((px, py)):
                left_anchor_pt = (px, py)
                break
            iL -= 1

        # Walk right
        right_anchor_pt = None
        iR = best_idx
        while iR < len(self._full_path_xy):
            px, py = self._full_path_xy[iR]
            if is_anchor((px, py)):
                right_anchor_pt = (px, py)
                break
            iR += 1

        # If we can't find distinct anchors on left & right,
        # just insert before E.
        if not left_anchor_pt or not right_anchor_pt:
            self._insert_anchor_point(-1, x_new, y_new)
            return
        if left_anchor_pt == right_anchor_pt:
            self._insert_anchor_point(-1, x_new, y_new)
            return

        # Convert anchor coords -> anchor_points indices
        left_idx = None
        right_idx = None
        for i, (ax, ay) in enumerate(self.anchor_points):
            if approx_equal(ax, ay, left_anchor_pt[0], left_anchor_pt[1]):
                left_idx = i
            if approx_equal(ax, ay, right_anchor_pt[0], right_anchor_pt[1]):
                right_idx = i

        if left_idx is None or right_idx is None:
            self._insert_anchor_point(-1, x_new, y_new)
            return

        # Insert between them
        if left_idx < right_idx:
            insert_idx = left_idx + 1
        else:
            insert_idx = right_idx + 1

        self._insert_anchor_point(insert_idx, x_new, y_new, label="", removable=True,
                                  z_val=1, radius=self.dot_radius)

    # --------------------------------------------------------------------
    # COST IMAGE
    # --------------------------------------------------------------------
    def _revert_cost_to_original(self):
        if self.cost_image_original is not None:
            self.cost_image = self.cost_image_original.copy()

    def _apply_all_guide_points_to_cost(self):
        if self.cost_image is None:
            return
        for i, (ax, ay) in enumerate(self.anchor_points):
            if self.point_items[i].is_removable():
                self._lower_cost_in_circle(ax, ay, self.radius_cost_image)

    def _lower_cost_in_circle(self, x_f, y_f, radius):
        if self.cost_image is None:
            return
        h, w = self.cost_image.shape
        row_c = int(round(y_f))
        col_c = int(round(x_f))
        if not (0 <= row_c < h and 0 <= col_c < w):
            return
        global_min = self.cost_image.min()
        r_s = max(0, row_c - radius)
        r_e = min(h, row_c + radius + 1)
        c_s = max(0, col_c - radius)
        c_e = min(w, col_c + radius + 1)
        for rr in range(r_s, r_e):
            for cc in range(c_s, c_e):
                dist = math.sqrt((rr - row_c)**2 + (cc - col_c)**2)
                if dist <= radius:
                    self.cost_image[rr, cc] = global_min

    # --------------------------------------------------------------------
    # PATH BUILDING
    # --------------------------------------------------------------------
    def _rebuild_full_path(self):
        for item in self.full_path_points:
            self.scene.removeItem(item)
        self.full_path_points.clear()
        self._full_path_xy.clear()

        if len(self.anchor_points) < 2 or self.cost_image is None:
            return

        big_xy = []
        for i in range(len(self.anchor_points) - 1):
            xA, yA = self.anchor_points[i]
            xB, yB = self.anchor_points[i + 1]
            sub_xy = self._compute_subpath_xy(xA, yA, xB, yB)
            if i == 0:
                big_xy.extend(sub_xy)
            else:
                if len(sub_xy) > 1:
                    big_xy.extend(sub_xy[1:])

        if len(big_xy) >= self._savgol_window_length:
            arr_xy = np.array(big_xy)
            smoothed = savgol_filter(
                arr_xy,
                window_length=self._savgol_window_length,
                polyorder=self._savgol_polyorder,
                axis=0
            )
            big_xy = smoothed.tolist()

        self._full_path_xy = big_xy[:]

        n_points = len(big_xy)
        for i, (px, py) in enumerate(big_xy):
            fraction = i / (n_points - 1) if n_points > 1 else 0
            color = Qt.red
            if self._rainbow_enabled:
                color = self._rainbow_color(fraction)

            path_item = LabeledPointItem(px, py, label="",
                                         radius=self.path_radius,
                                         color=color,
                                         removable=False,
                                         z_value=0)
            self.full_path_points.append(path_item)
            self.scene.addItem(path_item)

        # Keep anchor labels on top
        for p_item in self.point_items:
            if p_item._text_item:
                p_item.setZValue(100)

    def _compute_subpath_xy(self, xA, yA, xB, yB):
        if self.cost_image is None:
            return []
        h, w = self.cost_image.shape
        rA, cA = int(round(yA)), int(round(xA))
        rB, cB = int(round(yB)), int(round(xB))
        rA = max(0, min(rA, h - 1))
        cA = max(0, min(cA, w - 1))
        rB = max(0, min(rB, h - 1))
        cB = max(0, min(cB, w - 1))
        try:
            path_rc = find_path(self.cost_image, [(rA, cA), (rB, cB)])
        except ValueError as e:
            print("Error in find_path:", e)
            return []
        # Convert from (row, col) to (x, y)
        return [(c, r) for (r, c) in path_rc]

    def _rainbow_color(self, fraction):
        hue = int(300 * fraction)
        saturation = 255
        value = 255
        return QColor.fromHsv(hue, saturation, value)

    # --------------------------------------------------------------------
    # MOUSE EVENTS
    # --------------------------------------------------------------------
    def mousePressEvent(self, event):
        if event.button() == Qt.LeftButton:
            self._mouse_pressed = True
            self._was_dragging = False
            self._press_view_pos = event.pos()

            idx = self._find_item_near(event.pos(), threshold=10)
            if idx is not None:
                self._dragging_idx = idx
                self._drag_counter = 0
                scene_pos = self.mapToScene(event.pos())
                px, py = self.point_items[idx].get_pos()
                self._drag_offset = (scene_pos.x() - px, scene_pos.y() - py)
                self.setCursor(Qt.ClosedHandCursor)
                return

        elif event.button() == Qt.RightButton:
            self._remove_point_by_click(event.pos())

        super().mousePressEvent(event)

    def mouseMoveEvent(self, event):
        if self._dragging_idx is not None:
            scene_pos = self.mapToScene(event.pos())
            x_new = scene_pos.x() - self._drag_offset[0]
            y_new = scene_pos.y() - self._drag_offset[1]

            r = self.point_items[self._dragging_idx]._r
            x_clamped = self._clamp(x_new, r, self._img_w - r)
            y_clamped = self._clamp(y_new, r, self._img_h - r)
            self.point_items[self._dragging_idx].set_pos(x_clamped, y_clamped)

            self._drag_counter += 1
            # Update path every 4 moves
            if self._drag_counter >= 4:
                self._drag_counter = 0
                self._revert_cost_to_original()
                self._apply_all_guide_points_to_cost()
                self.anchor_points[self._dragging_idx] = (x_clamped, y_clamped)
                self._rebuild_full_path()
        else:
            if self._mouse_pressed and (event.buttons() & Qt.LeftButton):
                dist = (event.pos() - self._press_view_pos).manhattanLength()
                if dist > self._drag_threshold:
                    self._was_dragging = True

        super().mouseMoveEvent(event)

    def mouseReleaseEvent(self, event):
        super().mouseReleaseEvent(event)
        if event.button() == Qt.LeftButton and self._mouse_pressed:
            self._mouse_pressed = False
            self.setCursor(Qt.ArrowCursor)

            if self._dragging_idx is not None:
                idx = self._dragging_idx
                self._dragging_idx = None
                self._drag_offset = (0, 0)
                newX, newY = self.point_items[idx].get_pos()
                self.anchor_points[idx] = (newX, newY)
                self._revert_cost_to_original()
                self._apply_all_guide_points_to_cost()
                self._rebuild_full_path()
            else:
                # No drag => add point
                if not self._was_dragging:
                    scene_pos = self.mapToScene(event.pos())
                    x, y = scene_pos.x(), scene_pos.y()
                    self._add_guide_point(x, y)

            self._was_dragging = False

    def _remove_point_by_click(self, view_pos):
        idx = self._find_item_near(view_pos, threshold=10)
        if idx is None:
            return
        if not self.point_items[idx].is_removable():
            return

        self.scene.removeItem(self.point_items[idx])
        self.point_items.pop(idx)
        self.anchor_points.pop(idx)

        self._revert_cost_to_original()
        self._apply_all_guide_points_to_cost()
        self._rebuild_full_path()

    def _find_item_near(self, view_pos, threshold=10):
        scene_pos = self.mapToScene(view_pos)
        x_click, y_click = scene_pos.x(), scene_pos.y()

        closest_idx = None
        min_dist = float('inf')
        for i, itm in enumerate(self.point_items):
            d = itm.distance_to(x_click, y_click)
            if d < min_dist:
                min_dist = d
                closest_idx = i
        if closest_idx is not None and min_dist <= threshold:
            return closest_idx
        return None

    # --------------------------------------------------------------------
    # UTILS
    # --------------------------------------------------------------------
    def _clamp(self, val, mn, mx):
        return max(mn, min(val, mx))

    def _clear_all_points(self):
        for it in self.point_items:
            self.scene.removeItem(it)
        self.point_items.clear()
        self.anchor_points.clear()

        for p in self.full_path_points:
            self.scene.removeItem(p)
        self.full_path_points.clear()
        self._full_path_xy.clear()

    def clear_guide_points(self):
        i = 0
        while i < len(self.anchor_points):
            if self.point_items[i].is_removable():
                self.scene.removeItem(self.point_items[i])
                del self.point_items[i]
                del self.anchor_points[i]
            else:
                i += 1

        for it in self.full_path_points:
            self.scene.removeItem(it)
        self.full_path_points.clear()
        self._full_path_xy.clear()

        self._revert_cost_to_original()
        self._apply_all_guide_points_to_cost()
        self._rebuild_full_path()

    def get_full_path_xy(self):
        return self._full_path_xy


# ------------------------------------------------------------------------
# Advanced Settings Widget
# ------------------------------------------------------------------------
class AdvancedSettingsWidget(QWidget):
    """
    Shows toggle rainbow, circle editor, line smoothing slider, contrast slider,
    plus two image previews (contrasted-blurred and cost).
    The images should maintain aspect ratio upon resize.
    
    Now displays the images stacked vertically with labels above them.
    """
    def __init__(self, main_window, parent=None):
        super().__init__(parent)
        self._main_window = main_window

        self._last_cb_pix = None   # store QPixmap for contrasted-blurred
        self._last_cost_pix = None # store QPixmap for cost

        main_layout = QVBoxLayout()
        self.setLayout(main_layout)

        # A small grid for controls
        controls_layout = QGridLayout()

        # 1) Rainbow toggle
        self.btn_toggle_rainbow = QPushButton("Toggle Rainbow")
        self.btn_toggle_rainbow.clicked.connect(self._on_toggle_rainbow)
        controls_layout.addWidget(self.btn_toggle_rainbow, 0, 0)

        # 2) Circle editor
        self.btn_circle_editor = QPushButton("Open Circle Editor")
        self.btn_circle_editor.clicked.connect(self._main_window.open_circle_editor)
        controls_layout.addWidget(self.btn_circle_editor, 0, 1)

        # 3) Line smoothing slider + label
        self._lab_smoothing = QLabel("Line smoothing (7)")
        controls_layout.addWidget(self._lab_smoothing, 1, 0)
        self.line_smoothing_slider = QSlider(Qt.Horizontal)
        self.line_smoothing_slider.setRange(3, 51)
        self.line_smoothing_slider.setValue(7)
        self.line_smoothing_slider.valueChanged.connect(self._on_line_smoothing_slider)
        controls_layout.addWidget(self.line_smoothing_slider, 1, 1)

        # 4) Contrast slider + label
        self._lab_contrast = QLabel("Contrast (0.01)")
        controls_layout.addWidget(self._lab_contrast, 2, 0)
        self.contrast_slider = QSlider(Qt.Horizontal)
        self.contrast_slider.setRange(0, 100)
        self.contrast_slider.setValue(1)  # i.e. 0.01
        self.contrast_slider.valueChanged.connect(self._on_contrast_slider)
        controls_layout.addWidget(self.contrast_slider, 2, 1)

        main_layout.addLayout(controls_layout)

        # We'll set a minimum width so that the main window expands
        # rather than overlapping the image
        self.setMinimumWidth(350)

        # Now a vertical layout for the two images, each with a label above it
        images_layout = QVBoxLayout()

        # 1) Contrasted-blurred label + image
        self.label_cb_title = QLabel("Contrasted Blurred Image")
        self.label_cb_title.setAlignment(Qt.AlignCenter)
        images_layout.addWidget(self.label_cb_title)

        self.label_contrasted_blurred = QLabel()
        self.label_contrasted_blurred.setAlignment(Qt.AlignCenter)
        self.label_contrasted_blurred.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
        images_layout.addWidget(self.label_contrasted_blurred)

        # 2) Cost image label + image
        self.label_cost_title = QLabel("Current COST IMAGE")
        self.label_cost_title.setAlignment(Qt.AlignCenter)
        images_layout.addWidget(self.label_cost_title)

        self.label_cost_image = QLabel()
        self.label_cost_image.setAlignment(Qt.AlignCenter)
        self.label_cost_image.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
        images_layout.addWidget(self.label_cost_image)

        main_layout.addLayout(images_layout)

    def showEvent(self, event):
        """ When shown, ask parent to resize to accommodate. """
        super().showEvent(event)
        if self.parentWidget():
            self.parentWidget().adjustSize()

    def resizeEvent(self, event):
        """
        Keep the images at correct aspect ratio by re-scaling
        our stored pixmaps to the new label sizes.
        """
        super().resizeEvent(event)
        self._update_labels()

    def _update_labels(self):
        if self._last_cb_pix is not None:
            scaled_cb = self._last_cb_pix.scaled(
                self.label_contrasted_blurred.size(),
                Qt.KeepAspectRatio,
                Qt.SmoothTransformation
            )
            self.label_contrasted_blurred.setPixmap(scaled_cb)

        if self._last_cost_pix is not None:
            scaled_cost = self._last_cost_pix.scaled(
                self.label_cost_image.size(),
                Qt.KeepAspectRatio,
                Qt.SmoothTransformation
            )
            self.label_cost_image.setPixmap(scaled_cost)

    def _on_toggle_rainbow(self):
        self._main_window.toggle_rainbow()

    def _on_line_smoothing_slider(self, value):
        self._lab_smoothing.setText(f"Line smoothing ({value})")
        self._main_window.image_view.set_savgol_window_length(value)

    def _on_contrast_slider(self, value):
        clip_limit = value / 100.0
        self._lab_contrast.setText(f"Contrast ({clip_limit:.2f})")
        self._main_window.update_contrast(clip_limit)

    def update_displays(self, contrasted_img_np, cost_img_np):
        """
        Called by main_window to refresh the two images in the advanced panel.
        We'll store them as QPixmaps, then do the re-scale in _update_labels().
        """
        cb_pix = self._np_array_to_qpixmap(contrasted_img_np)
        cost_pix = self._np_array_to_qpixmap(cost_img_np, normalize=True)

        self._last_cb_pix = cb_pix
        self._last_cost_pix = cost_pix
        self._update_labels()

    def _np_array_to_qpixmap(self, arr, normalize=False):
        if arr is None:
            return None
        arr_ = arr.copy()
        if normalize:
            mn, mx = arr_.min(), arr_.max()
            if abs(mx - mn) < 1e-12:
                arr_[:] = 0
            else:
                arr_ = (arr_ - mn) / (mx - mn)
        arr_ = np.clip(arr_, 0, 1)
        arr_255 = (arr_ * 255).astype(np.uint8)

        h, w = arr_255.shape
        qimage = QImage(arr_255.data, w, h, w, QImage.Format_Grayscale8)
        return QPixmap.fromImage(qimage)


# ------------------------------------------------------------------------
# Main Window
# ------------------------------------------------------------------------
class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Test GUI")

        self._last_loaded_pixmap = None
        self._circle_calibrated_radius = 6
        self._last_loaded_file_path = None

        # For the contrast slider
        self._current_clip_limit = 0.01

        # Outer widget + layout
        self._main_widget = QWidget()
        self._main_layout = QHBoxLayout(self._main_widget)
        self._left_panel = QVBoxLayout()
        self._main_layout.addLayout(self._left_panel)
        self.setCentralWidget(self._main_widget)

        # Image view
        self.image_view = ImageGraphicsView()
        self._left_panel.addWidget(self.image_view)

        # Button row
        btn_layout = QHBoxLayout()
        self.btn_load_image = QPushButton("Load Image")
        self.btn_load_image.clicked.connect(self.load_image)
        btn_layout.addWidget(self.btn_load_image)

        self.btn_export_path = QPushButton("Export Path")
        self.btn_export_path.clicked.connect(self.export_path)
        btn_layout.addWidget(self.btn_export_path)

        self.btn_clear_points = QPushButton("Clear Points")
        self.btn_clear_points.clicked.connect(self.clear_points)
        btn_layout.addWidget(self.btn_clear_points)

        # "Advanced Settings" toggle
        self.btn_advanced = QPushButton("Advanced Settings")
        self.btn_advanced.setCheckable(True)
        self.btn_advanced.clicked.connect(self._toggle_advanced_settings)
        btn_layout.addWidget(self.btn_advanced)

        self._left_panel.addLayout(btn_layout)

        # Advanced settings widget
        self._advanced_widget = AdvancedSettingsWidget(self)
        self._advanced_widget.hide()
        self._main_layout.addWidget(self._advanced_widget)

        self.resize(1000, 600)
        self._old_central_widget = None
        self._editor = None

    def _toggle_advanced_settings(self, checked):
        if checked:
            self._advanced_widget.show()
        else:
            self._advanced_widget.hide()
        self.adjustSize()

    def open_circle_editor(self):
        """ Replace central widget with circle editor. """
        if not self._last_loaded_pixmap:
            print("No image loaded yet! Cannot open circle editor.")
            return

        old_widget = self.takeCentralWidget()
        self._old_central_widget = old_widget

        init_radius = self._circle_calibrated_radius
        editor = CircleEditorWidget(
            pixmap=self._last_loaded_pixmap,
            init_radius=init_radius,
            done_callback=self._on_circle_editor_done
        )
        self._editor = editor
        self.setCentralWidget(editor)

    def _on_circle_editor_done(self, final_radius):