Move contents labels management to cursor mod

Add a new type/api to manage "contents labels" (labels that sit in
a view and display info about viewed data) since it's mostly used by
the linked charts cursor. Make `LinkedSplits.cursor` the new and only
instance var for the cursor such that charts can look it up from that
common class. Drop the `ChartPlotWidget._ohlc` array, just add
a `'ohlc'` entry to `._arrays`.

piker/ui/_chart.py

@@ -20,7 +20,7 @@ High level Qt chart widgets.
 """
 import time
 from contextlib import AsyncExitStack
-from typing import Tuple, Dict, Any, Optional, Callable
+from typing import Tuple, Dict, Any, Optional
 from types import ModuleType
 from functools import partial
 
@@ -261,7 +261,7 @@ class LinkedSplits(QtGui.QWidget):
         super().__init__()
 
         # self.signals_visible: bool = False
-        self._cursor: Cursor = None  # crosshair graphics
+        self.cursor: Cursor = None  # crosshair graphics
 
         self.godwidget = godwidget
         self.chart: ChartPlotWidget = None  # main (ohlc) chart
@@ -326,7 +326,7 @@ class LinkedSplits(QtGui.QWidget):
         The data input struct array must include OHLC fields.
         """
         # add crosshairs
-        self._cursor = Cursor(
+        self.cursor = Cursor(
             linkedsplits=self,
             digits=symbol.digits(),
         )
@@ -338,7 +338,7 @@ class LinkedSplits(QtGui.QWidget):
             _is_main=True,
         )
         # add crosshair graphic
-        self.chart.addItem(self._cursor)
+        self.chart.addItem(self.cursor)
 
         # axis placement
         if _xaxis_at == 'bottom':
@@ -392,7 +392,7 @@ class LinkedSplits(QtGui.QWidget):
                 'left': PriceAxis(linkedsplits=self, orientation='left'),
             },
             viewBox=cv,
-            cursor=self._cursor,
+            # cursor=self.cursor,
             **cpw_kwargs,
         )
         print(f'xaxis ps: {xaxis.pos()}')
@@ -412,7 +412,7 @@ class LinkedSplits(QtGui.QWidget):
         cpw.setXLink(self.chart)
 
         # add to cross-hair's known plots
-        self._cursor.add_plot(cpw)
+        self.cursor.add_plot(cpw)
 
         # draw curve graphics
         if style == 'bar':
@@ -493,15 +493,19 @@ class ChartPlotWidget(pg.PlotWidget):
         )
         self.name = name
         self._lc = linkedsplits
+        self.linked = linkedsplits
 
         # scene-local placeholder for book graphics
         # sizing to avoid overlap with data contents
         self._max_l1_line_len: float = 0
 
         # self.setViewportMargins(0, 0, 0, 0)
-        self._ohlc = array  # readonly view of ohlc data
+        # self._ohlc = array  # readonly view of ohlc data
 
-        self._arrays = {}  # readonly view of overlays
+        # readonly view of data arrays
+        self._arrays = {
+            'ohlc': array,
+        }
         self._graphics = {}  # registry of underlying graphics
         self._overlays = set()  # registry of overlay curve names
 
@@ -510,9 +514,7 @@ class ChartPlotWidget(pg.PlotWidget):
 
         self._vb = self.plotItem.vb
         self._static_yrange = static_yrange  # for "known y-range style"
-
         self._view_mode: str = 'follow'
-        self._cursor = cursor  # placehold for mouse
 
         # show only right side axes
         self.hideAxis('left')
@@ -539,25 +541,10 @@ class ChartPlotWidget(pg.PlotWidget):
         self._vb.setFocus()
 
     def last_bar_in_view(self) -> int:
-        self._ohlc[-1]['index']
+        self._arrays['ohlc'][-1]['index']
 
-    def update_contents_labels(
+    def is_valid_index(self, index: int) -> bool:
-        self,
+        return index >= 0 and index < self._arrays['ohlc'][-1]['index']
-        index: int,
-        # array_name: str,
-    ) -> None:
-        if index >= 0 and index < self._ohlc[-1]['index']:
-            for name, (label, update) in self._labels.items():
-
-                if name is self.name:
-                    array = self._ohlc
-                else:
-                    array = self._arrays[name]
-
-                try:
-                    update(index, array)
-                except IndexError:
-                    log.exception(f"Failed to update label: {name}")
 
     def _set_xlimits(
         self,
@@ -581,11 +568,11 @@ class ChartPlotWidget(pg.PlotWidget):
         """Return a range tuple for the bars present in view.
         """
         l, r = self.view_range()
-        a = self._ohlc
+        a = self._arrays['ohlc']
         lbar = max(l, a[0]['index'])
         rbar = min(r, a[-1]['index'])
         # lbar = max(l, 0)
-        # rbar = min(r, len(self._ohlc))
+        # rbar = min(r, len(self._arrays['ohlc']))
         return l, lbar, rbar, r
 
     def default_view(
@@ -595,7 +582,7 @@ class ChartPlotWidget(pg.PlotWidget):
         """Set the view box to the "default" startup view of the scene.
 
         """
-        xlast = self._ohlc[index]['index']
+        xlast = self._arrays['ohlc'][index]['index']
         begin = xlast - _bars_to_left_in_follow_mode
         end = xlast + _bars_from_right_in_follow_mode
 
@@ -650,12 +637,12 @@ class ChartPlotWidget(pg.PlotWidget):
 
         self._graphics[name] = graphics
 
-        self.add_contents_label(
+        self.linked.cursor.contents_labels.add_label(
-            name,
+            self,
+            'ohlc',
             anchor_at=('top', 'left'),
             update_func=ContentsLabel.update_from_ohlc,
         )
-        self.update_contents_labels(len(data) - 1)
 
         self._add_sticky(name)
 
@@ -727,32 +714,18 @@ class ChartPlotWidget(pg.PlotWidget):
             # (we need something that avoids clutter on x-axis).
             self._add_sticky(name, bg_color='default_light')
 
-        if add_label:
+        if self.linked.cursor:
-            self.add_contents_label(name, anchor_at=anchor_at)
+            self.linked.cursor.add_curve_cursor(self, curve)
-            self.update_contents_labels(len(data) - 1)
 
-        if self._cursor:
+            if add_label:
-            self._cursor.add_curve_cursor(self, curve)
+                self.linked.cursor.contents_labels.add_label(
+                    self,
+                    name,
+                    anchor_at=anchor_at
+                )
 
         return curve
 
-    def add_contents_label(
-        self,
-        name: str,
-        anchor_at: Tuple[str, str] = ('top', 'left'),
-        update_func: Callable = ContentsLabel.update_from_value,
-    ) -> ContentsLabel:
-
-        label = ContentsLabel(chart=self, anchor_at=anchor_at)
-        self._labels[name] = (
-            # calls class method on instance
-            label,
-            partial(update_func, label, name)
-        )
-        label.show()
-
-        return label
-
     def _add_sticky(
         self,
         name: str,
@@ -787,7 +760,7 @@ class ChartPlotWidget(pg.PlotWidget):
         """Update the named internal graphics from ``array``.
 
         """
-        self._ohlc = array
+        self._arrays['ohlc'] = array
         graphics = self._graphics[name]
         graphics.update_from_array(array, **kwargs)
         return graphics
@@ -803,7 +776,7 @@ class ChartPlotWidget(pg.PlotWidget):
         """
 
         if name not in self._overlays:
-            self._ohlc = array
+            self._arrays['ohlc'] = array
         else:
             self._arrays[name] = array
 
@@ -857,10 +830,10 @@ class ChartPlotWidget(pg.PlotWidget):
             # TODO: logic to check if end of bars in view
             # extra = view_len - _min_points_to_show
 
-            # begin = self._ohlc[0]['index'] - extra
+            # begin = self._arrays['ohlc'][0]['index'] - extra
 
-            # # end = len(self._ohlc) - 1 + extra
+            # # end = len(self._arrays['ohlc']) - 1 + extra
-            # end = self._ohlc[-1]['index'] - 1 + extra
+            # end = self._arrays['ohlc'][-1]['index'] - 1 + extra
 
             # XXX: test code for only rendering lines for the bars in view.
             # This turns out to be very very poor perf when scaling out to
@@ -879,9 +852,9 @@ class ChartPlotWidget(pg.PlotWidget):
             # self._set_xlimits(begin, end)
 
             # TODO: this should be some kind of numpy view api
-            # bars = self._ohlc[lbar:rbar]
+            # bars = self._arrays['ohlc'][lbar:rbar]
 
-            a = self._ohlc
+            a = self._arrays['ohlc']
             ifirst = a[0]['index']
             bars = a[lbar - ifirst:rbar - ifirst + 1]
 
@@ -952,84 +925,6 @@ class ChartPlotWidget(pg.PlotWidget):
         self.scene().leaveEvent(ev)
 
 
-async def test_bed(
-    ohlcv,
-    chart,
-    lc,
-):
-    from ._graphics._lines import order_line
-
-    sleep = 6
-
-    # from PyQt5.QtCore import QPointF
-    vb = chart._vb
-    # scene = vb.scene()
-
-    # raxis = chart.getAxis('right')
-    # vb_right = vb.boundingRect().right()
-
-    last, i_end = ohlcv.array[-1][['close', 'index']]
-
-    line = order_line(
-        chart,
-        level=last,
-        level_digits=2
-    )
-    # eps = line.getEndpoints()
-
-    # llabel = line._labels[1][1]
-
-    line.update_labels({'level': last})
-    return
-
-    # rl = eps[1]
-    # rlabel.setPos(rl)
-
-    # ti = pg.TextItem(text='Fuck you')
-    # ti.setPos(pg.Point(i_end, last))
-    # ti.setParentItem(line)
-    # ti.setAnchor(pg.Point(1, 1))
-    # vb.addItem(ti)
-    # chart.plotItem.addItem(ti)
-
-    from ._label import Label
-
-    txt = Label(
-        vb,
-        fmt_str='fuck {it}',
-    )
-    txt.format(it='boy')
-    txt.place_on_scene('left')
-    txt.set_view_y(last)
-
-    # txt = QtGui.QGraphicsTextItem()
-    # txt.setPlainText("FUCK YOU")
-    # txt.setFont(_font.font)
-    # txt.setDefaultTextColor(pg.mkColor(hcolor('bracket')))
-    # # txt.setParentItem(vb)
-    # w = txt.boundingRect().width()
-    # scene.addItem(txt)
-
-    # txt.setParentItem(line)
-    # d_coords = vb.mapFromView(QPointF(i_end, last))
-    # txt.setPos(vb_right - w, d_coords.y())
-    # txt.show()
-    # txt.update()
-
-    # rlabel.setPos(vb_right - 2*w, d_coords.y())
-    # rlabel.show()
-
-    i = 0
-    while True:
-        await trio.sleep(sleep)
-        await tractor.breakpoint()
-        txt.format(it=f'dog_{i}')
-        # d_coords = vb.mapFromView(QPointF(i_end, last))
-        # txt.setPos(vb_right - w, d_coords.y())
-        # txt.setPlainText(f"FUCK YOU {i}")
-        i += 1
-
-
 _clear_throttle_rate: int = 60  # Hz
 _book_throttle_rate: int = 16  # Hz
 
@@ -1065,7 +960,7 @@ async def chart_from_quotes(
         # https://arxiv.org/abs/cs/0610046
         # https://github.com/lemire/pythonmaxmin
 
-        array = chart._ohlc
+        array = chart._arrays['ohlc']
         ifirst = array[0]['index']
 
         last_bars_range = chart.bars_range()
@@ -1385,7 +1280,7 @@ async def run_fsp(
             )
 
             # display contents labels asap
-            chart.update_contents_labels(
+            chart.linked.cursor.contents_labels.update_labels(
                 len(shm.array) - 1,
                 # fsp_func_name
             )

piker/ui/_graphics/_cursor.py

@@ -18,8 +18,8 @@
 Mouse interaction graphics
 
 """
-import math
+from functools import partial
-from typing import Optional, Tuple, Set, Dict
+from typing import Optional, Callable
 
 import inspect
 import numpy as np
@@ -30,7 +30,6 @@ from PyQt5.QtCore import QPointF, QRectF
 from .._style import (
     _xaxis_at,
     hcolor,
-    _font,
     _font_small,
 )
 from .._axes import YAxisLabel, XAxisLabel
@@ -98,7 +97,7 @@ class LineDot(pg.CurvePoint):
 
         (x, y) = self.curve().getData()
         index = self.property('index')
-        # first = self._plot._ohlc[0]['index']
+        # first = self._plot._arrays['ohlc'][0]['index']
         # first = x[0]
         # i = index - first
         i = index - x[0]
@@ -133,11 +132,15 @@ class ContentsLabel(pg.LabelItem):
     }
 
     def __init__(
+
         self,
-        chart: 'ChartPlotWidget',  # noqa
+        # chart: 'ChartPlotWidget',  # noqa
+        view: pg.ViewBox,
+
         anchor_at: str = ('top', 'right'),
         justify_text: str = 'left',
         font_size: Optional[int] = None,
+
     ) -> None:
 
         font_size = font_size or _font_small.px_size
@@ -148,9 +151,10 @@ class ContentsLabel(pg.LabelItem):
         )
 
         # anchor to viewbox
-        self.setParentItem(chart._vb)
+        self.setParentItem(view)
-        chart.scene().addItem(self)
+
-        self.chart = chart
+        self.vb = view
+        view.scene().addItem(self)
 
         v, h = anchor_at
         index = (self._corner_anchors[h], self._corner_anchors[v])
@@ -163,10 +167,12 @@ class ContentsLabel(pg.LabelItem):
         self.anchor(itemPos=index, parentPos=index, offset=margins)
 
     def update_from_ohlc(
+
         self,
         name: str,
         index: int,
         array: np.ndarray,
+
     ) -> None:
         # this being "html" is the dumbest shit :eyeroll:
         first = array[0]['index']
@@ -188,25 +194,111 @@ class ContentsLabel(pg.LabelItem):
         )
 
     def update_from_value(
+
         self,
         name: str,
         index: int,
         array: np.ndarray,
+
     ) -> None:
+
         first = array[0]['index']
         if index < array[-1]['index'] and index > first:
             data = array[index - first][name]
             self.setText(f"{name}: {data:.2f}")
 
 
+class ContentsLabels:
+    '''Collection of labels that span a ``LinkedSplits`` set of chart plots
+    and can be updated from the underlying data from an x-index value sent
+    as input from a cursor or other query mechanism.
+
+    '''
+    def __init__(
+        self,
+        linkedsplits: 'LinkedSplits',  # type: ignore # noqa
+
+    ) -> None:
+
+        self.linkedsplits = linkedsplits
+        self._labels: list[(
+            'CharPlotWidget',  # type: ignore # noqa
+            str,
+            ContentsLabel,
+            Callable
+        )] = []
+
+    def update_labels(
+        self,
+        index: int,
+        # array_name: str,
+
+    ) -> None:
+        # for name, (label, update) in self._labels.items():
+        for chart, name, label, update in self._labels:
+
+            if not (index >= 0 and index < chart._arrays['ohlc'][-1]['index']):
+                # out of range
+                continue
+
+            array = chart._arrays[name]
+
+            # call provided update func with data point
+            try:
+                label.show()
+                update(index, array)
+
+            except IndexError:
+                log.exception(f"Failed to update label: {name}")
+
+    def hide(self) -> None:
+        for chart, name, label, update in self._labels:
+            label.hide()
+
+    def add_label(
+
+        self,
+        chart: 'ChartPlotWidget',  # type: ignore # noqa
+        name: str,
+        anchor_at: tuple[str, str] = ('top', 'left'),
+        update_func: Callable = ContentsLabel.update_from_value,
+
+    ) -> ContentsLabel:
+
+        label = ContentsLabel(
+            view=chart._vb,
+            anchor_at=anchor_at,
+        )
+        self._labels.append(
+            (chart, name, label, partial(update_func, label, name))
+        )
+        # label.hide()
+
+        return label
+
+
 class Cursor(pg.GraphicsObject):
 
     def __init__(
+
         self,
         linkedsplits: 'LinkedSplits',  # noqa
         digits: int = 0
+
     ) -> None:
+
         super().__init__()
+
+        self.linked = linkedsplits
+        self.graphics: dict[str, pg.GraphicsObject] = {}
+        self.plots: List['PlotChartWidget'] = []  # type: ignore # noqa
+        self.active_plot = None
+        self.digits: int = digits
+        self._datum_xy: tuple[int, float] = (0, 0)
+
+        self._hovered: set[pg.GraphicsObject] = set()
+        self._trackers: set[pg.GraphicsObject] = set()
+
         # XXX: not sure why these are instance variables?
         # It's not like we can change them on the fly..?
         self.pen = pg.mkPen(
@@ -217,19 +309,10 @@ class Cursor(pg.GraphicsObject):
             color=hcolor('davies'),
             style=QtCore.Qt.DashLine,
         )
-        self.lsc = linkedsplits
-        self.graphics: Dict[str, pg.GraphicsObject] = {}
-        self.plots: List['PlotChartWidget'] = []  # type: ignore # noqa
-        self.active_plot = None
-        self.digits: int = digits
-        self._datum_xy: Tuple[int, float] = (0, 0)
-
-        self._hovered: Set[pg.GraphicsObject] = set()
-        self._trackers: Set[pg.GraphicsObject] = set()
 
         # value used for rounding y-axis discreet tick steps
         # computing once, up front, here cuz why not
-        self._y_incr_mult = 1 / self.lsc._symbol.tick_size
+        self._y_incr_mult = 1 / self.linked._symbol.tick_size
 
         # line width in view coordinates
         self._lw = self.pixelWidth() * self.lines_pen.width()
@@ -239,6 +322,22 @@ class Cursor(pg.GraphicsObject):
 
         self._y_label_update: bool = True
 
+        self.contents_labels = ContentsLabels(self.linked)
+        self._in_query_mode: bool = False
+
+    @property
+    def in_query_mode(self) -> bool:
+        return self._in_query_mode
+
+    @in_query_mode.setter
+    def in_query_mode(self, value: bool) -> None:
+        if self._in_query_mode and not value:
+
+            # edge trigger hide all labels
+            self.contents_labels.hide()
+
+        self._in_query_mode = value
+
     def add_hovered(
         self,
         item: pg.GraphicsObject,
@@ -320,7 +419,7 @@ class Cursor(pg.GraphicsObject):
         # the current sample under the mouse
         cursor = LineDot(
             curve,
-            index=plot._ohlc[-1]['index'],
+            index=plot._arrays['ohlc'][-1]['index'],
             plot=plot
         )
         plot.addItem(cursor)
@@ -344,7 +443,7 @@ class Cursor(pg.GraphicsObject):
 
     def mouseMoved(
         self,
-        evt: 'Tuple[QMouseEvent]',  # noqa
+        evt: 'tuple[QMouseEvent]',  # noqa
     ) -> None:  # noqa
         """Update horizonal and vertical lines when mouse moves inside
         either the main chart or any indicator subplot.
@@ -392,10 +491,16 @@ class Cursor(pg.GraphicsObject):
                 item.on_tracked_source(ix, iy)
 
         if ix != last_ix:
+
+            if self.in_query_mode:
+                # show contents labels on all linked charts and update
+                # with cursor movement
+                self.contents_labels.update_labels(ix)
+
             for plot, opts in self.graphics.items():
 
                 # update the chart's "contents" label
-                plot.update_contents_labels(ix)
+                # plot.update_contents_labels(ix)
 
                 # move the vertical line to the current "center of bar"
                 opts['vl'].setX(ix + line_offset)