Diagnostics as dialogs (no dock) + real car-style gauges

Diagnostics: removed the always-on right-side Diagnostics dock (it ate screen
space on every view). Read Codes now opens a modal dialog listing codes
grouped stored/pending/permanent with descriptions (no-start codes bold red);
Clear Codes keeps its confirmation, and on re-read pops a dialog only if codes
returned. Dropped the View > Show Diagnostics Panel toggle.

Gauges: replaced the plain progress-arc with a proper automotive dial -- round
face + bezel, major/minor tick marks, a numeric scale (rounded labels), a red
needle + center hub, a colored rim arc for the value, and an amber peak tick.
Digital readout + name/unit below.

Validated headless: no Diagnostics dock; Read Codes opens the Trouble Codes
dialog; gauge view renders. obdcore + diagnostics tests still pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016yT89n4zR4qbrySoSiEyZs

gui/main.py

@@ -46,7 +46,6 @@ class MainWindow(QtWidgets.QMainWindow):
         self._build_menubar()
         self._build_connection_bar()
         self._build_pid_browser()
-        self._build_diag_dock()
         self._build_center()
         self._build_statusbar()
         self._refresh_title()
@@ -93,9 +92,6 @@ class MainWindow(QtWidgets.QMainWindow):
         self.show_pids = self._act(viewm, "Show PID Panel", self._toggle_pid_dock,
                                    checkable=True)
         self.show_pids.setChecked(True)
-        self.show_diag = self._act(viewm, "Show Diagnostics Panel", self._toggle_diag_dock,
-                                   checkable=True)
-        self.show_diag.setChecked(True)
         self.norm_act = self._act(viewm, "Normalize Graph (% of range)",
                                   self._sync_norm_from_menu, checkable=True)
         viewm.addSeparator()
@@ -213,53 +209,24 @@ class MainWindow(QtWidgets.QMainWindow):
         self.tree.resizeColumnToContents(0)
         self.tree.blockSignals(False)
 
-    # ---------- diagnostics dock (DTCs) ----------
+    # ---------- diagnostics (DTCs) -- menu-driven dialogs, no docked panel ----------
-    def _build_diag_dock(self):
-        self.diag_dock = QtWidgets.QDockWidget("Diagnostics", self)
-        wrap = QtWidgets.QWidget()
-        lay = QtWidgets.QVBoxLayout(wrap)
-        lay.setContentsMargins(4, 4, 4, 4)
-        bar = QtWidgets.QHBoxLayout()
-        self.diag_read_btn = QtWidgets.QPushButton("Read Codes")
-        self.diag_read_btn.clicked.connect(self._read_codes)
-        self.diag_clear_btn = QtWidgets.QPushButton("Clear Codes…")
-        self.diag_clear_btn.clicked.connect(self._clear_codes)
-        bar.addWidget(self.diag_read_btn)
-        bar.addWidget(self.diag_clear_btn)
-        bar.addStretch(1)
-        lay.addLayout(bar)
-        self.diag_tree = QtWidgets.QTreeWidget()
-        self.diag_tree.setColumnCount(3)
-        self.diag_tree.setHeaderLabels(["Code", "Description", "System"])
-        self.diag_tree.setRootIsDecorated(True)
-        self.diag_tree.header().setStretchLastSection(False)
-        self.diag_tree.header().setSectionResizeMode(
-            1, QtWidgets.QHeaderView.Stretch)
-        lay.addWidget(self.diag_tree)
-        self.diag_hint = QtWidgets.QLabel(
-            "Connect, then Read Codes.  Bold red = no-start / drive-disabling.")
-        self.diag_hint.setWordWrap(True)
-        lay.addWidget(self.diag_hint)
-        self.diag_dock.setWidget(wrap)
-        self.diag_dock.visibilityChanged.connect(
-            lambda vis: self.show_diag.setChecked(vis))
-        self.addDockWidget(QtCore.Qt.RightDockWidgetArea, self.diag_dock)
-
     _DIAG_GROUPS = [("stored", "Stored (mode 03)"),
                     ("pending", "Pending (mode 07)"),
                     ("permanent", "Permanent (mode 0A)")]
 
-    def _populate_diag(self, codes):
+    def _codes_tree(self, codes):
-        """codes: {'stored':[...], 'pending':[...], 'permanent':[...]}"""
+        """Build a populated QTreeWidget of codes for a dialog (not docked)."""
-        self.diag_tree.clear()
+        tree = QtWidgets.QTreeWidget()
+        tree.setColumnCount(3)
+        tree.setHeaderLabels(["Code", "Description", "System"])
+        tree.header().setSectionResizeMode(1, QtWidgets.QHeaderView.Stretch)
         total = 0
         for bucket, label in self._DIAG_GROUPS:
             lst = codes.get(bucket, [])
             total += len(lst)
             top = QtWidgets.QTreeWidgetItem([f"{label}  ({len(lst)})", "", ""])
             f = top.font(0); f.setBold(True); top.setFont(0, f)
-            top.setFirstColumnSpanned(False)
+            tree.addTopLevelItem(top)
-            self.diag_tree.addTopLevelItem(top)
             if not lst:
                 none = QtWidgets.QTreeWidgetItem(["—", "(no codes)", ""])
                 none.setForeground(1, QtGui.QBrush(QtGui.QColor("#888")))
@@ -267,18 +234,33 @@ class MainWindow(QtWidgets.QMainWindow):
             for code in lst:
                 d = self.ctl.dtcdb.get(code)
                 it = QtWidgets.QTreeWidgetItem([code, d.desc, d.system])
-                it.setData(0, QtCore.Qt.UserRole, code)
                 if getattr(d, "no_start", False):
                     red = QtGui.QBrush(QtGui.QColor("#e6194B"))
                     bf = it.font(0); bf.setBold(True)
                     for c in range(3):
-                        it.setFont(c, bf)
+                        it.setFont(c, bf); it.setForeground(c, red)
-                        it.setForeground(c, red)
                     it.setToolTip(0, "No-start / drive-disabling fault")
                 top.addChild(it)
             top.setExpanded(True)
-        self.diag_tree.resizeColumnToContents(0)
+        tree.resizeColumnToContents(0)
-        self.diag_tree.resizeColumnToContents(2)
+        tree.resizeColumnToContents(2)
+        return tree, total
+
+    def _show_codes_dialog(self, codes, title, header=""):
+        dlg = QtWidgets.QDialog(self)
+        dlg.setWindowTitle(title)
+        dlg.resize(560, 360)
+        lay = QtWidgets.QVBoxLayout(dlg)
+        tree, total = self._codes_tree(codes)
+        if header:
+            lbl = QtWidgets.QLabel(header); lbl.setWordWrap(True); lay.addWidget(lbl)
+        lay.addWidget(tree)
+        foot = QtWidgets.QLabel("Bold red = no-start / drive-disabling fault.")
+        foot.setStyleSheet("color:#888;"); lay.addWidget(foot)
+        bb = QtWidgets.QDialogButtonBox(QtWidgets.QDialogButtonBox.Close)
+        bb.rejected.connect(dlg.reject); bb.accepted.connect(dlg.accept)
+        lay.addWidget(bb)
+        dlg.exec()
         return total
 
     def _read_codes(self):
@@ -289,17 +271,10 @@ class MainWindow(QtWidgets.QMainWindow):
         try:
             codes = self.ctl.read_dtcs()
         except Exception as e:
-            QtWidgets.QMessageBox.critical(self, "Read failed", str(e))
+            QtWidgets.QMessageBox.critical(self, "Read failed", str(e)); return
-            return
+        total = self._show_codes_dialog(codes, "Trouble Codes")
-        total = self._populate_diag(codes)
+        self.status.showMessage(f"Read codes: {total} found." if total
-        self.diag_dock.setVisible(True)
+                                else "Read codes: none stored.")
-        self.show_diag.setChecked(True)
-        self.status.showMessage(
-            f"Read codes: {total} found "
-            f"(stored {len(codes.get('stored', []))}, "
-            f"pending {len(codes.get('pending', []))}, "
-            f"permanent {len(codes.get('permanent', []))})."
-            if total else "Read codes: none stored.")
 
     def _clear_codes(self):
         if not self.ctl.connected:
@@ -310,8 +285,8 @@ class MainWindow(QtWidgets.QMainWindow):
             self, "Clear codes?",
             "This erases stored + pending codes AND freeze-frame data, and "
             "resets emissions monitors.\n\n"
-            "Write the codes down first — and read them on a no-start before "
+            "Read the codes first — on a no-start especially.  If the fault is "
-            "clearing.  If the fault is still present the code comes right back.\n"
+            "still present the code comes right back.\n"
             "Permanent codes (mode 0A) will NOT clear until the fault is fixed "
             "and the vehicle self-clears them over several drive cycles.\n\n"
             "Clear codes now?",
@@ -323,32 +298,30 @@ class MainWindow(QtWidgets.QMainWindow):
         try:
             ok = self.ctl.clear_dtcs()
         except Exception as e:
-            QtWidgets.QMessageBox.critical(self, "Clear failed", str(e))
+            QtWidgets.QMessageBox.critical(self, "Clear failed", str(e)); return
-            return
         if not ok:
             QtWidgets.QMessageBox.warning(
                 self, "No acknowledgement",
                 "The ECU did not acknowledge the clear.\n"
-                "Make sure the key is in RUN and the vehicle is connected, then "
+                "Make sure the key is in RUN and connected, then try again.")
-                "try again.")
             self.status.showMessage("Clear not acknowledged by ECU.")
             return
-        # Re-read immediately so anything that came straight back is shown.
         try:
             codes = self.ctl.read_dtcs()
         except Exception:
             codes = {}
-        returned = self._populate_diag(codes)
+        returned = sum(len(codes.get(b, [])) for b, _ in self._DIAG_GROUPS)
         if returned:
-            self.status.showMessage(
+            self._show_codes_dialog(
-                f"Cleared — but {returned} code(s) returned immediately "
+                codes, "Cleared — codes returned",
-                "(active fault present).")
+                "These codes came back immediately after clearing — an active "
+                "fault is still present:")
+            self.status.showMessage(f"Cleared — {returned} code(s) returned (active fault).")
         else:
+            QtWidgets.QMessageBox.information(self, "Codes cleared",
+                                              "Cleared. No codes on re-read.")
             self.status.showMessage("Cleared. No codes on re-read.")
 
-    def _toggle_diag_dock(self):
-        self.diag_dock.setVisible(self.show_diag.isChecked())
-
     # ---------- center (graph + table stack) ----------
     def _build_center(self):
         self.stack = QtWidgets.QStackedWidget()

gui/widgets.py

@@ -156,7 +156,7 @@ class ArcGauge(QtWidgets.QWidget):
         self.accent = QtGui.QColor(accent)
         self.value = None
         self.peak = None
-        self.setMinimumSize(150, 130)
+        self.setMinimumSize(172, 176)
 
     def set_value(self, v, peak=None):
         self.value = v
@@ -166,45 +166,93 @@ class ArcGauge(QtWidgets.QWidget):
     def _frac(self, v):
         return max(0.0, min(1.0, (v - self.vmin) / (self.vmax - self.vmin)))
 
+    # gauge geometry: a 270-degree dial, gap at the bottom (like a tach)
+    _START = 225.0       # value=min angle (math degrees, 0=3 o'clock, CCW+)
+    _SWEEP = 270.0       # clockwise as value rises
+
+    def _ang(self, frac):
+        return self._START - self._SWEEP * max(0.0, min(1.0, frac))
+
     def paintEvent(self, _ev):
         p = QtGui.QPainter(self)
         p.setRenderHint(QtGui.QPainter.Antialiasing)
         w, h = self.width(), self.height()
-        p.fillRect(self.rect(), QtGui.QColor("#141414"))   # own dark bg (theme-proof)
+        p.fillRect(self.rect(), QtGui.QColor("#141414"))
-        m = 14
-        side = min(w, h - 18)
-        rect = QtCore.QRectF((w - side) / 2 + m / 2, m / 2, side - m, side - m)
-        start, span = 225 * 16, -270 * 16            # 270deg sweep, top-open down
 
-        def arc_pen(color, width):
+        side = min(w, h - 14)
-            pen = QtGui.QPen(QtGui.QColor(color), width)
+        R = side / 2 - 6
-            pen.setCapStyle(QtCore.Qt.RoundCap)
+        cx, cy = w / 2.0, R + 8
-            return pen
 
-        p.setPen(arc_pen("#333", 9))
+        def pt(ang_deg, r):
-        p.drawArc(rect, start, span)
+            a = math.radians(ang_deg)
+            return QtCore.QPointF(cx + r * math.cos(a), cy - r * math.sin(a))
 
+        # dial face + bezel
+        p.setPen(QtGui.QPen(QtGui.QColor("#2a2a2a"), 3))
+        p.setBrush(QtGui.QColor("#0c0c0c"))
+        p.drawEllipse(QtCore.QPointF(cx, cy), R, R)
+
+        # value progress arc just inside the rim
+        rimrect = QtCore.QRectF(cx - R + 7, cy - R + 7, 2 * (R - 7), 2 * (R - 7))
         if self.value is not None:
-            frac = self._frac(self.value)
+            pen = QtGui.QPen(QtGui.QColor(self.accent), 4)
-            p.setPen(arc_pen(self.accent, 9))
+            pen.setCapStyle(QtCore.Qt.FlatCap)
-            p.drawArc(rect, start, int(span * frac))
+            p.setPen(pen)
-            if self.peak is not None and self.peak != self.value:
+            p.drawArc(rimrect, int(self._START * 16),
-                pf = self._frac(self.peak)
+                      int(-self._SWEEP * self._frac(self.value) * 16))
-                ang = (225 - 270 * pf)
-                p.setPen(QtGui.QPen(QtGui.QColor("#e6c84b"), 2))
-                cx, cy = rect.center().x(), rect.center().y()
-                r1, r2 = side / 2 - m - 9, side / 2 - m + 2
-                a = math.radians(ang)
-                p.drawLine(QtCore.QPointF(cx + r1 * math.cos(a), cy - r1 * math.sin(a)),
-                           QtCore.QPointF(cx + r2 * math.cos(a), cy - r2 * math.sin(a)))
 
-        p.setPen(QtGui.QColor("#eee"))
+        # tick marks + numeric scale
-        f = p.font(); f.setPointSize(15); f.setBold(True); p.setFont(f)
+        majors = 6
+        fnt = p.font(); fnt.setPointSize(7); p.setFont(fnt)
+        for i in range(majors * 5 + 1):
+            frac = i / (majors * 5)
+            a = self._ang(frac)
+            major = (i % 5 == 0)
+            p.setPen(QtGui.QPen(QtGui.QColor("#ddd" if major else "#555"),
+                                2 if major else 1))
+            p.drawLine(pt(a, R - 3), pt(a, R - (13 if major else 7)))
+            if major:
+                val = self.vmin + frac * (self.vmax - self.vmin)
+                span = abs(self.vmax - self.vmin)
+                lbl = f"{val:.0f}" if span >= 50 else f"{val:.1f}" if span >= 5 else f"{val:g}"
+                lp = pt(a, R - 25)
+                p.setPen(QtGui.QColor("#9a9a9a"))
+                p.drawText(QtCore.QRectF(lp.x() - 18, lp.y() - 7, 36, 14),
+                           QtCore.Qt.AlignCenter, lbl)
+
+        # peak marker (thin amber tick)
+        if self.peak is not None and self.value is not None and self.peak != self.value:
+            a = self._ang(self._frac(self.peak))
+            p.setPen(QtGui.QPen(QtGui.QColor("#e6c84b"), 2))
+            p.drawLine(pt(a, R - 3), pt(a, R - 14))
+
+        # needle
+        if self.value is not None:
+            a = self._ang(self._frac(self.value))
+            tip = pt(a, R - 16)
+            b1 = pt(a + 90, 4.5)
+            b2 = pt(a - 90, 4.5)
+            tail = pt(a + 180, 10)
+            path = QtGui.QPainterPath()
+            path.moveTo(b1); path.lineTo(tip); path.lineTo(b2); path.lineTo(tail)
+            path.closeSubpath()
+            p.setPen(QtCore.Qt.NoPen)
+            p.setBrush(QtGui.QColor("#e6194B"))
+            p.drawPath(path)
+        # hub
+        p.setBrush(QtGui.QColor("#999")); p.setPen(QtCore.Qt.NoPen)
+        p.drawEllipse(QtCore.QPointF(cx, cy), 5, 5)
+
+        # digital readout (lower face)
+        p.setPen(QtGui.QColor("#fff"))
+        fnt.setPointSize(13); fnt.setBold(True); p.setFont(fnt)
         val = "--" if self.value is None else f"{self.value:g}"
-        p.drawText(rect, QtCore.Qt.AlignCenter, val)
+        p.drawText(QtCore.QRectF(cx - 55, cy + R * 0.30, 110, 22),
-        f.setPointSize(8); f.setBold(False); p.setFont(f)
+                   QtCore.Qt.AlignCenter, val)
-        p.setPen(QtGui.QColor("#999"))
+        # name + unit
-        p.drawText(QtCore.QRectF(0, h - 16, w, 14), QtCore.Qt.AlignCenter,
+        fnt.setPointSize(8); fnt.setBold(False); p.setFont(fnt)
+        p.setPen(QtGui.QColor("#9a9a9a"))
+        p.drawText(QtCore.QRectF(0, h - 15, w, 14), QtCore.Qt.AlignCenter,
                    f"{self.name}  ({self.unit})" if self.unit else self.name)
         p.end()