feat(console): add app controller, main menu and statistics screen

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

console/screens/estadisticas.py

@@ -0,0 +1,167 @@
+"""
+Statistics dashboard screen for the AUTOPARTES console application.
+
+Displays database table counts and coverage metrics retrieved via
+:meth:`Database.get_stats`.
+"""
+
+from console.core.screens import Screen
+from console.core.keybindings import Key
+from console.config import APP_NAME, VERSION
+from console.utils.formatting import format_number
+
+
+# Human-readable labels for each database table counter.
+_TABLE_LABELS = [
+    ("brands",               "Marcas"),
+    ("models",               "Modelos"),
+    ("engines",              "Motores"),
+    ("years",                "Anos"),
+    ("part_categories",      "Categorias"),
+    ("part_groups",          "Grupos de Partes"),
+    ("parts",                "Partes OEM"),
+    ("aftermarket_parts",    "Partes Aftermarket"),
+    ("manufacturers",        "Fabricantes"),
+    ("part_cross_references","Cross-References"),
+]
+
+# Footer key labels
+_FOOTER = [
+    ("F5", "Refrescar"),
+    ("F10", "Menu"),
+    ("ESC", "Atras"),
+]
+
+
+class EstadisticasScreen(Screen):
+    """Read-only statistics dashboard showing database counters."""
+
+    def __init__(self):
+        super().__init__(name="estadisticas", title="Estadisticas del Sistema")
+        self._stats = None
+
+    # ------------------------------------------------------------------
+    # Helpers
+    # ------------------------------------------------------------------
+
+    def _load_stats(self, db):
+        """Fetch fresh statistics from the database."""
+        try:
+            self._stats = db.get_stats()
+        except Exception:
+            self._stats = None
+
+    def _build_fields(self):
+        """Build the detail fields list from the cached stats dict."""
+        if self._stats is None:
+            return [("Error", "No se pudieron cargar las estadisticas")]
+
+        fields = []
+
+        # -- Section: BASE DE DATOS --
+        for key, label in _TABLE_LABELS:
+            value = self._stats.get(key, 0)
+            fields.append((label, format_number(value)))
+
+        return fields
+
+    def _build_coverage_fields(self):
+        """Build coverage / summary fields."""
+        if self._stats is None:
+            return []
+
+        fields = []
+
+        # Vehicle-part fitments
+        fitments = self._stats.get("vehicle_parts", 0)
+        fields.append(("Fitments", format_number(fitments)))
+
+        # Top brands by fitment count
+        top_brands = self._stats.get("top_brands", [])
+        if top_brands:
+            parts = []
+            for b in top_brands[:5]:
+                parts.append(f"{b['name']}({format_number(b['count'])})")
+            fields.append(("Top marcas", "  ".join(parts)))
+
+        return fields
+
+    # ------------------------------------------------------------------
+    # Screen interface
+    # ------------------------------------------------------------------
+
+    def render(self, context, db, renderer):
+        # Load stats on first render (or after refresh)
+        if self._stats is None:
+            self._load_stats(db)
+
+        # Header
+        renderer.draw_header(
+            f" {APP_NAME} v{VERSION}",
+            " Estadisticas ",
+        )
+
+        h, w = renderer.get_size()
+
+        # -- Section title: BASE DE DATOS --
+        section_title = " BASE DE DATOS "
+        border_char = "\u2500"  # ─
+        pad_len = max(w - 4 - len(section_title), 0)
+        section_line = border_char * 2 + section_title + border_char * pad_len
+        renderer.draw_text(3, 2, section_line[:w - 4], "title")
+
+        # Database counters
+        db_fields = self._build_fields()
+        max_label = max((len(lbl) for lbl, _ in db_fields), default=10)
+        dot_total = max_label + 4
+
+        row = 5
+        for label, value in db_fields:
+            if row >= h - 6:
+                break
+            dots = "." * (dot_total - len(label))
+            label_part = f"  {label}{dots}: "
+            renderer.draw_text(row, 0, label_part, "field_label")
+            renderer.draw_text(row, len(label_part), str(value), "field_value")
+            row += 1
+
+        # -- Section title: COBERTURA --
+        row += 1
+        if row < h - 5:
+            section_title2 = " COBERTURA "
+            pad_len2 = max(w - 4 - len(section_title2), 0)
+            section_line2 = border_char * 2 + section_title2 + border_char * pad_len2
+            renderer.draw_text(row, 2, section_line2[:w - 4], "title")
+            row += 2
+
+            coverage_fields = self._build_coverage_fields()
+            cov_max_label = max(
+                (len(lbl) for lbl, _ in coverage_fields), default=10
+            )
+            cov_dot_total = cov_max_label + 4
+
+            for label, value in coverage_fields:
+                if row >= h - 3:
+                    break
+                dots = "." * (cov_dot_total - len(label))
+                label_part = f"  {label}{dots}: "
+                renderer.draw_text(row, 0, label_part, "field_label")
+                renderer.draw_text(
+                    row, len(label_part), str(value), "field_value"
+                )
+                row += 1
+
+        # Footer
+        renderer.draw_footer(_FOOTER)
+
+    def on_key(self, key, context, db, renderer, nav):
+        # F5: refresh stats
+        if key == Key.F5:
+            self._stats = None  # will reload on next render
+            return None
+
+        # ESC or Backspace: go back
+        if key in (Key.ESCAPE, Key.BACKSPACE):
+            return "back"
+
+        return None