Analysis: read a rarely-read meter as coarse, not absent; newest rows first

Three things a reported Heizoel page got wrong at once. Its tank is dipped
a few times a year and its burner read every few months, which is exactly
the shape the coverage rules had not been walked through.

"No data" for data that exists. A tank books nothing until the next
dipstick closes the interval, so the stretch after the last dipstick is
covered by no run at all, and a bucket no run covers was reported missing.
The burner, whose run reaches into the window, said "only coarser data" --
the honest answer -- so one card claimed there was nothing while the
coverage panel beside it listed years of data. A bucket that no run covers,
no gap overlaps and no opening balance explains now reports the meter's
resolution when its preceding coverage is within one interval of its own
class: it is not silent, it is read rarely. A meter that does book its own
buckets and stops -- a dead hourly source, a sheet asked about a later
month -- still reads missing.

Auto answering twelve months with one bar. Coarse only means "longer than
a month", so a dipstick taken each autumn straddles a New Year as surely
as a month start: coarsening the chart to years bought nothing and cost
every point. The planning resolution now caps coarse at month when a run
crosses a local year edge, and a series that cannot resolve the natural
size no longer coarsens the whole chart -- it is drawn at that size with
its buckets marked, which the chart and table already explain.

A page contradicting itself. The comparison line above the ranking was fed
the leading measure's matched coverage but worded as if it spoke for the
page, directly above a burner row that did compare. It now names the figure
it is about.

Alongside: the "largest changes" ranking no longer drops a meter whose
change is not comparable. It ranks what can be ranked, then lists the rest
with their values and the reason -- the tank had been vanishing from its
own energy type. And every dated table now reads newest first, as lists
are read; charts stay chronological left to right, and the CSV export
stays ascending for spreadsheets.

A-41 to A-43 in the note record the three rules.

src/App/Components/Pages/Admin/Tariffs.razor

@@ -233,7 +233,8 @@ else
     private async Task LoadAsync()
     {
         await using var db = await DbFactory.CreateDbContextAsync();
-        _tariffs = await db.Tariffs.AsNoTracking().OrderBy(t => t.Component).ThenBy(t => t.ValidFrom).ToListAsync();
+        // By component, then the newest validity first (A-42): a price history is read from the price that applies now.
+        _tariffs = await db.Tariffs.AsNoTracking().OrderBy(t => t.Component).ThenByDescending(t => t.ValidFrom).ToListAsync();
         _effectiveEnds = TariffValidity.EffectiveEnds(
             _tariffs.Select(t => new TariffSpan(t.Id, t.ScopeType, t.ScopeId, t.Component, t.ValidFrom, t.ValidTo)));
         _energyTypes = await db.EnergyTypes.AsNoTracking().OrderBy(t => t.DisplayName).ToListAsync();

src/App/Components/Pages/Dashboard.razor

@@ -120,7 +120,7 @@
             @* The ranges compared; the matched stretch only when less than the whole periods is compared (D-07). *@
             <ComparisonSummary Period="view.Period" Resolution="view.Data.Comparison"
                                Matched="@(view.Data.CostChange.IsPartial || view.Data.CostChange.Basis == CostChangeBasis.NotComparable ? view.Data.CostChange.Matched : null)"
-                               Class="mt-3" />
+                               Subject="@S.AnalysisTable_Cost" Class="mt-3" />
 
             <MudGrid Spacing="3" Class="mt-1">
                 <MudItem xs="12">

src/App/Components/Pages/Energy/EnergyHistoryTab.razor

@@ -40,7 +40,8 @@
     }
     else
     {
-        <ComparisonSummary Period="Analysis.Period" Resolution="ComparisonResolution()" Matched="_view.Main?.Comparison?.Matched" Class="mb-3" />
+        <ComparisonSummary Period="Analysis.Period" Resolution="ComparisonResolution()" Matched="_view.Main?.Comparison?.Matched"
+                           Subject="@MainName()" Class="mb-3" />
         <AnalysisChart Buckets="_buckets" Series="_view.Chart" ComparisonPairs="_pairs" Title="@_title" OnBucketClick="_onBucketClick"
                        Resolution="_view.Coarsest" OnUseBucket="UseBucket" />
 
@@ -188,6 +189,12 @@
     private MeterVault.Core.Analysis.Coverage.AvailableRange? Availability() =>
         _view?.Main?.Availability ?? _quantities?.Availability.Quantity;
 
+    /// <summary>
+    /// The name of the series the comparison line speaks of, when the view charts several whose matched coverage
+    /// may differ (A-41); null when it charts one and the line cannot be misread.
+    /// </summary>
+    private string? MainName() => _view is { Table.Count: > 1 } view ? view.Table[0].Name : null;
+
     private ComparisonResolution? ComparisonResolution() =>
         _view?.Metric == AnalysisMetric.Cost ? Analysis.CostComparison?.Resolution : _quantities?.Comparison?.Resolution;
 

src/App/Components/Pages/Energy/EnergyOverviewTab.razor

@@ -1,5 +1,6 @@
 @using MeterVault.App.Energy
 @using MeterVault.Core.Analysis
+@using MeterVault.Core.Analysis.Coverage
 @using MeterVault.Core.Analysis.Totals
 @using MeterVault.Infrastructure.Analysis
 @inject NavigationManager Nav
@@ -59,7 +60,8 @@ else
         }
     </MudGrid>
 
-    <ComparisonSummary Period="Analysis.Period" Resolution="_quantities.Comparison?.Resolution" Matched="_main?.Comparison?.Matched" Class="mt-3 mb-4" />
+    <ComparisonSummary Period="Analysis.Period" Resolution="_quantities.Comparison?.Resolution" Matched="_main?.Comparison?.Matched"
+                       Subject="@_comparisonSubject" Class="mt-3 mb-4" />
 
     <MudGrid Spacing="3">
         <MudItem xs="12" md="8">
@@ -69,7 +71,7 @@ else
                     <MudLink Href="@HistoryHref(_main is null ? null : AnalysisMetrics.MetricOf(_main.Kind))" Typo="Typo.body2">@S.EnergyView_OpenHistory</MudLink>
                 </div>
                 <AnalysisChart Buckets="_quantities.Plan.Buckets" Series="_trend" ComparisonPairs="_quantities.Comparison?.Buckets"
-                               Title="@_trendTitle" Height="240" />
+                               Title="@_trendTitle" Height="240" Resolution="_main?.Resolution" />
             </MudPaper>
         </MudItem>
         <MudItem xs="12" md="4">
@@ -102,6 +104,12 @@ else
                             {
                                 <div class="mv-cell-secondary">@detail</div>
                             }
+                            @* Its own dates whenever they are not the scope's: a measure counted by a tank dipped
+                               once a year must not be read against the range of the burner beside it (A-41). *@
+                            @if (OwnRange(series) is { } own)
+                            {
+                                <div class="mv-cell-secondary">@Loc.F(S.Empty_AvailableRange, Format.Date(own.FirstDay), Format.Date(own.LastDay))</div>
+                            }
                         </dd>
                     }
                 </dl>
@@ -109,18 +117,23 @@ else
         </MudItem>
         <MudItem xs="12">
             <MudPaper Outlined="true" Elevation="0" Class="pa-4">
+                @* A-43: the ranked changes, then every other meter that has data in either period — with its values and
+                   the status that says why there is no change. A meter with data is never silently left out. *@
                 <MudText Typo="Typo.h6">@S.EnergyView_LargestChanges</MudText>
                 @if (_quantities.Comparison is not { IsApplicable: true })
                 {
                     <MudText Typo="Typo.body2" Class="mv-muted mt-1">@S.EnergyView_NoComparison</MudText>
                 }
-                else if (_changes.Count == 0)
+                else if (_changes.IsEmpty)
                 {
                     <MudText Typo="Typo.body2" Class="mv-muted mt-1">@S.EnergyView_NoComparableMeters</MudText>
                 }
                 else
                 {
-                    <MudText Typo="Typo.caption" Class="mv-muted d-block mb-2">@S.EnergyView_LargestChangesNote</MudText>
+                    @if (_changes.Ranked.Count > 0)
+                    {
+                        <MudText Typo="Typo.caption" Class="mv-muted d-block mb-2">@S.EnergyView_LargestChangesNote</MudText>
+                    }
                     <div class="mv-table-scroll" role="region" aria-label="@S.EnergyView_LargestChanges" tabindex="0">
                         <MudSimpleTable Dense="true" Hover="true" Class="mv-analysis-table">
                             <thead>
@@ -132,17 +145,11 @@ else
                                 </tr>
                             </thead>
                             <tbody>
-                                @foreach (var change in _changes)
+                                @foreach (var change in _changes.Ranked)
                                 {
                                     var series = change.Series;
                                     <tr>
-                                        <th scope="row" class="mv-row-label">
-                                            <MudLink Href="@MeterLinks.Analysis(series.MeterId!.Value, Query)">@series.Name</MudLink>
-                                            @if (Analysis.TotalsOf(series.MeterId!.Value) is { IsCounted: false } entry)
-                                            {
-                                                <div class="mv-cell-secondary">@entry.Class.Display()</div>
-                                            }
-                                        </th>
+                                        <th scope="row" class="mv-row-label">@MeterCell(series)</th>
                                         <td class="mv-num">
                                             @Format.Quantity(change.Current, series.Unit)
                                             <div class="mv-cell-secondary">@Format.DateRange(change.Matched.Current!.FirstDay, change.Matched.Current.LastDay)</div>
@@ -158,8 +165,46 @@ else
                                     </tr>
                                 }
                             </tbody>
+                            @if (_changes.Rest.Count > 0)
+                            {
+                                <tbody>
+                                    @if (_changes.Ranked.Count > 0)
+                                    {
+                                        <tr class="mv-row-group">
+                                            <th scope="colgroup" colspan="4">
+                                                @S.EnergyView_ChangesRest
+                                                <div class="mv-cell-secondary">@S.EnergyView_ChangesRestNote</div>
+                                            </th>
+                                        </tr>
+                                    }
+                                    @foreach (var row in _changes.Rest)
+                                    {
+                                        var series = row.Series;
+                                        <tr>
+                                            <th scope="row" class="mv-row-label">@MeterCell(series)</th>
+                                            @FigureCell(row.Current, series)
+                                            @FigureCell(row.Comparison, series)
+                                            <td>
+                                                <ChangeChip Change="row.Change" Polarity="ChangePolarities.For(series.Kind)"
+                                                            FormatMagnitude="@(v => Format.Quantity(v, series.Unit))" />
+                                                @if (row.SharesNoDays)
+                                                {
+                                                    <div class="mv-cell-secondary">@S.Comparison_NotComparable</div>
+                                                }
+                                            </td>
+                                        </tr>
+                                    }
+                                </tbody>
+                            }
                         </MudSimpleTable>
                     </div>
+                    @if (_changes.Hidden > 0)
+                    {
+                        <MudText Typo="Typo.body2" Class="mv-muted mt-2">
+                            @Loc.F(S.EnergyView_MoreMeters, _changes.Shown, _changes.Shown + _changes.Hidden)
+                            <MudLink Href="@AnalysisLinks.EnergyType(Analysis.EnergyTypeId, AnalysisLinks.EnergyTabMeters, Query)" Typo="Typo.body2">@S.Nav_Meters</MudLink>
+                        </MudText>
+                    }
                 }
             </MudPaper>
         </MudItem>
@@ -192,9 +237,10 @@ else
     private List<AnalysisSeries> _measures = [];
     private AnalysisSeries? _main;
     private IReadOnlyList<AnalysisChartSeries> _trend = [];
-    private IReadOnlyList<MeterChange> _changes = [];
+    private MeterChangeList _changes = MeterChangeList.None;
     private string _trendTitle = string.Empty;
     private string? _comparisonCaption;
+    private string? _comparisonSubject;
     private string? _costBasis;
     private List<string> _costLines = [];
     private Change? _costChange;
@@ -224,6 +270,8 @@ else
         _noData = _measures.Count > 0 && _measures.All(s => s.Total.Status == BucketStatus.Missing && !s.IsPending);
         _comparisonCaption = _quantities.Comparison is { IsApplicable: true } ? Query.Comparison.Display() : null;
 
+        _comparisonSubject = _measures.Count > 1 && _main is { } named ? EnergyHistoryView.MeasureName(named, _measures) : null;
+
         if (_main is { } main)
         {
             var name = EnergyHistoryView.MeasureName(main, _measures);
@@ -242,10 +290,16 @@ else
             _trend = [];
         }
 
-        _changes = MeterChanges.Largest(_quantities.Series, MaxChanges);
+        _changes = MeterChanges.Of(_quantities.Series, MaxChanges);
         BuildCost();
     }
 
+    /// <summary>A measure's own availability when it differs from the scope's (A-41); null when they are the same.</summary>
+    private AvailableRange? OwnRange(AnalysisSeries series) =>
+        series.Availability is { } own && (_quantities?.Availability.Quantity is not { } scope || own.FirstDay != scope.FirstDay || own.LastDay != scope.LastDay)
+            ? own
+            : null;
+
     private void BuildCost()
     {
         _costBasis = null;
@@ -292,6 +346,32 @@ else
     private Change? ChangeOf(AnalysisSeries series) =>
         _quantities?.Comparison is { IsApplicable: true } ? series.Comparison?.Change ?? Change.Unavailable : null;
 
+    /// <summary>The meter's name, linked to its own analysis over the same period, and — when it is not counted in the totals — why.</summary>
+    private RenderFragment MeterCell(AnalysisSeries series) => __builder =>
+    {
+        <MudLink Href="@MeterLinks.Analysis(series.MeterId!.Value, Query)">@series.Name</MudLink>
+        @if (Analysis.TotalsOf(series.MeterId!.Value) is { IsCounted: false } entry)
+        {
+            <div class="mv-cell-secondary">@entry.Class.Display()</div>
+        }
+    };
+
+    /// <summary>
+    /// A total of a meter that is not ranked: its number, or the status in words instead of a fabricated 0 (§4.3). A
+    /// value that is not plain keeps its status beside it — that is the reason there is no change.
+    /// </summary>
+    private RenderFragment FigureCell(BucketValue value, AnalysisSeries series) => __builder =>
+    {
+        var status = FigureText.Of(value, Analysis.Names.MeterOrNull);
+        <td class="@(status.IsKnown ? "mv-num" : "mv-num mv-unknown")">
+            @(status.IsKnown ? Format.Quantity(value.Value, series.Unit) : Format.Unknown)
+            @if (!status.IsComplete)
+            {
+                <div class="mv-cell-secondary">@status.Summary</div>
+            }
+        </td>
+    };
+
     private string? MembersCaption(AnalysisSeries series) =>
         series.MemberIds.Count == 0 ? null : Loc.F(S.EnergyView_CountedMeters, string.Join(", ", series.MemberIds.Select(Analysis.MeterName)));
 

src/App/Components/Pages/MeterPage/MeterCoverageNote.razor

@@ -102,21 +102,14 @@
     @if (!View.Markers.IsEmpty)
     {
         <MudText Typo="Typo.subtitle1" Class="mt-4 mb-1">@S.MeterDetail_InThisPeriod</MudText>
+        @* One dated list, newest first (A-42): events and price changes interleave, so the dates never jump back up. *@
         <ul class="mv-markers">
-            @foreach (var e in View.Markers.Events)
+            @foreach (var marker in Markers)
             {
                 <li>
-                    <MudIcon Icon="@MeterEventText.Icon(e.Type)" Size="Size.Small" aria-hidden="true" />
-                    <span class="mv-markers__date">@Format.Date(PeriodResolver.LocalDate(e.Time, View.Period.Zone))</span>
-                    <span>@e.Type.Display()@EventDetail(e)</span>
-                </li>
-            }
-            @foreach (var t in View.Markers.TariffChanges)
-            {
-                <li>
-                    <MudIcon Icon="@Icons.Material.Filled.Sell" Size="Size.Small" aria-hidden="true" />
-                    <span class="mv-markers__date">@Format.Date(t.ValidFrom)</span>
-                    <span>@Loc.F(S.MeterDetail_TariffChange, t.Component.Display(), Format.Number(t.Value, 4), t.Unit, ScopeText(t))</span>
+                    <MudIcon Icon="@marker.Icon" Size="Size.Small" aria-hidden="true" />
+                    <span class="mv-markers__date">@Format.Date(marker.Day)</span>
+                    <span>@marker.Text</span>
                 </li>
             }
         </ul>
@@ -157,6 +150,9 @@
 
     private AnalysisSeries? Series => View.Series;
 
+    /// <summary>The events and tariff changes of the range as one dated list, newest first (A-42).</summary>
+    private IReadOnlyList<MeterMarker> Markers => MeterMarkerList.Of(View.Markers, View.Period.Zone, Detail.EnergyType);
+
     /// <summary>A first reading booked against the baseline with an unknown start (D-14) sits in the range.</summary>
     private bool HasOpeningBalance =>
         Series is { } s && (s.Total.Provenance.HasFlag(Provenance.OpeningBalance) || s.Values.Any(v => v.Provenance.HasFlag(Provenance.OpeningBalance)));
@@ -214,19 +210,4 @@
         return MeterLinks.Detail(block.MeterId, MeterLinks.TabNormalized, null, target);
     }
 
-    private static string EventDetail(EventRow e) => e.Type switch
-    {
-        MeterEventType.Delivery or MeterEventType.TankLevel when e.Amount is { } amount => $": {Format.Number(amount, 1)} {e.Unit}".TrimEnd(),
-        MeterEventType.MeterSwap or MeterEventType.CounterReset when e.PrevValue is not null || e.NewValue is not null =>
-            $": {(e.PrevValue is { } p ? Format.Number(p, 2) : Format.Unknown)} → {(e.NewValue is { } n ? Format.Number(n, 2) : Format.Unknown)}",
-        _ when !string.IsNullOrWhiteSpace(e.Notes) => ": " + e.Notes,
-        _ => string.Empty,
-    };
-
-    private string ScopeText(TariffRow tariff) => tariff.Scope switch
-    {
-        TariffScope.Meter => S.MeterDetail_ScopeThisMeter,
-        TariffScope.EnergyType => Detail.EnergyType,
-        _ => tariff.Scope.Display(),
-    };
 }

src/App/Components/Pages/Overview/OverviewCoverage.razor

@@ -43,8 +43,9 @@
     private int _stale;
 
     /// <summary>
-    /// The period as a whole: complete when every measure is, no data when none has any, being prepared while a rebuild
-    /// runs, partial otherwise. Without any meter, the bill's own availability (manual costs are always available).
+    /// The period as a whole: complete when every measure is, no data when none has any, only coarser data when every
+    /// measure has only that (A-41), being prepared while a rebuild runs, partial otherwise. Without any meter, the
+    /// bill's own availability (manual costs are always available).
     /// </summary>
     private BucketStatus PeriodStatus
     {
@@ -68,6 +69,7 @@
 
             return statuses.All(s => s == BucketStatus.Available) ? BucketStatus.Available
                 : statuses.All(s => s == BucketStatus.Missing) ? BucketStatus.Missing
+                : statuses.All(s => s == BucketStatus.Unresolved) ? BucketStatus.Unresolved
                 : BucketStatus.Partial;
         }
     }

src/App/Components/Pages/Specialized/SolarSiteSection.razor

@@ -105,7 +105,7 @@
         </MudGrid>
 
         <ComparisonSummary Period="Site.Quantities.Period" Resolution="Site.Quantities.Comparison?.Resolution"
-                           Matched="Site.Generation?.Comparison?.Matched" Class="mb-3" />
+                           Matched="Site.Generation?.Comparison?.Matched" Subject="@S.Solar_Generation" Class="mb-3" />
 
         <MudPaper Outlined="true" Elevation="0" Class="pa-4 mb-4">
             <MudText Typo="Typo.h6" Class="mb-2">@S.Solar_GenerationAndSelfConsumption</MudText>