using MeterVault.App;
using MeterVault.App.Analysis;
using MeterVault.App.Energy;
using MeterVault.Core.Analysis;
using MeterVault.Core.Analysis.Coverage;
using MeterVault.Core.Analysis.Totals;
using MeterVault.Core.Domain;
using MeterVault.Infrastructure.Analysis;
using MeterVault.Infrastructure.Dashboard;
using static MeterVault.Integration.Tests.Analysis.AnalysisUiTestData;

namespace MeterVault.Integration.Tests.Analysis;

/// <summary>
/// The energy type page and the meter lists without a database (brief §7.3): the tab and view keys, which metrics a type
/// charts, how a meter counts in words (a breakdown names its parent, a calculated view its sources), meter rows that say
/// "No data" instead of a made-up zero, the largest changes over matched coverage, the flow table's words, and the
/// connection rules — no meter into itself, no duplicate, no loop, no silent change to a calculation.
/// </summary>
public sealed class EnergyPageTests
{
    // ------------------------------------------------------------------------------------------------ keys

    [Theory]
    [InlineData("http://x/energy/3", "overview", "total")]
    [InlineData("http://x/energy/3?tab=history", "history", "total")]
    [InlineData("http://x/energy/3?tab=HISTORY&view=Meters", "history", "meters")]
    [InlineData("http://x/energy/3?tab=flow&period=ytd", "flow", "total")]
    [InlineData("http://x/energy/3?tab=meters&view=bogus", "meters", "total")]
    [InlineData("http://x/energy/3?tab=sankey", "overview", "total")]
    [InlineData("/energy/3?view=meters#top", "overview", "meters")]
    public void Tab_and_view_keys_resolve_with_fallbacks(string uri, string tab, string view)
    {
        var (resolvedTab, resolvedView) = EnergyPageKeys.Parse(uri);

        Assert.Equal(tab, resolvedTab);
        Assert.Equal(view, resolvedView);
        Assert.Equal(AnalysisLinks.EnergyTabs.ToList().IndexOf(tab), AnalysisLinks.EnergyTabIndex(resolvedTab));
    }

    [Fact]
    public void The_tab_and_view_are_not_part_of_the_analysis_state()
    {
        // A tab or view switch must not reload the analysis (D-46): the parsed query is the same with or without them.
        var defaults = AnalysisDefaults.History.ForScope(QueryScope.ForEnergyType(3));
        var plain = AnalysisQuery.Parse("/energy/3?period=ytd", defaults);
        var tabbed = AnalysisQuery.Parse("/energy/3?tab=history&view=meters&period=ytd", defaults);

        Assert.Equal(plain, tabbed);
        Assert.Equal("/energy/3?tab=history&period=ytd", AnalysisLinks.EnergyType(3, AnalysisLinks.EnergyTabHistory, plain));
    }

    // ------------------------------------------------------------------------------------------------ metrics

    [Fact]
    public void A_type_charts_the_metrics_of_its_measures_and_meters_and_its_cost()
    {
        var buckets = Buckets(D(2025, 1, 1), D(2025, 3, 31));
        var use = Measure(TotalsMeasure.Use, QuantityKind.Consumption, buckets);
        var generation = Measure(TotalsMeasure.Generation, QuantityKind.Generation, buckets);
        var net = Series(9, "Balance", [Available(1), Available(-2), Available(3)], kind: QuantityKind.Net);
        var result = Result(buckets, [net], [generation, use]);

        var metrics = EnergyMetrics.Available(result, cost: null);

        Assert.Equal([AnalysisMetric.Consumption, AnalysisMetric.Generation, AnalysisMetric.Net], metrics);
        Assert.Equal(AnalysisMetric.Consumption, EnergyMetrics.Effective(null, metrics));
        Assert.Equal(AnalysisMetric.Generation, EnergyMetrics.Effective(AnalysisMetric.Generation, metrics));
        Assert.Equal(AnalysisMetric.Consumption, EnergyMetrics.Effective(AnalysisMetric.Balance, metrics));
        Assert.Equal([use], EnergyMetrics.MeasuresOf(result, AnalysisMetric.Consumption));
        Assert.Equal([net], EnergyMetrics.MetersOf(result, AnalysisMetric.Net));
        Assert.Empty(EnergyMetrics.MeasuresOf(result, AnalysisMetric.Net));
    }

    // ------------------------------------------------------------------------------------------------ memberships

    [Fact]
    public void A_breakdown_names_its_parent_and_a_calculated_view_its_sources() => In("en", () =>
    {
        var names = new Dictionary<int, string> { [1] = "Haus", [4] = "Solar 1", [5] = "Solar 2" };
        string Name(int id) => names[id];

        var breakdown = MeterMembership.Of(Entry(3, MeterTotalsClass.Breakdown, MeterTotalsReason.ContainedByLink, parents: [1]), null, Name)!;
        Assert.Equal("Breakdown of a counted meter", breakdown.Label);
        Assert.Equal("Part of Haus: shown, but never added on top.", breakdown.Detail);
        Assert.False(breakdown.IsCounted);

        var sum = Series(9, "Summe Solar", [Available(1)], kind: QuantityKind.Generation) with
        {
            Virtual = new VirtualSeriesInfo(VirtualMeterStatus.Valid, "m4 + m5", MeterVault.Core.Analysis.Virtual.VirtualCostRule.None, [4, 5], [4, 5], [], null, null),
        };
        var view = MeterMembership.Of(Entry(9, MeterTotalsClass.AnalysisOnly, MeterTotalsReason.VirtualView), sum, Name)!;
        Assert.Equal("Analysis only", view.Label);
        Assert.Contains("Solar 1, Solar 2", view.Detail, StringComparison.Ordinal);

        var grid = MeterMembership.Of(Entry(2, MeterTotalsClass.GridImport, MeterTotalsReason.GridImportRole, measure: TotalsMeasure.GridImport), null, Name)!;
        Assert.True(grid.IsCounted);
        Assert.Contains("never added", grid.Detail, StringComparison.Ordinal);

        Assert.Null(MeterMembership.Of(null, null, Name));
    });

    [Fact]
    public void Membership_wording_is_german_in_german() => In("de", () =>
    {
        var membership = MeterMembership.Of(Entry(3, MeterTotalsClass.Breakdown, MeterTotalsReason.ContainedByLink, parents: [1]), null, _ => "Zähler Haus")!;

        Assert.Equal("Aufschlüsselung eines gezählten Zählers", membership.Label);
        Assert.Equal("Teil von Zähler Haus: wird gezeigt, aber nie zusätzlich addiert.", membership.Detail);
    });

    // ------------------------------------------------------------------------------------------------ meter rows

    [Fact]
    public void A_meter_without_data_reads_no_data_and_a_measured_zero_reads_zero() => In("en", () =>
    {
        var buckets = Buckets(D(2025, 1, 1), D(2025, 2, 28));
        var silent = Series(1, "Silent", [Missing(), Missing()], BucketValue.Missing());
        var idle = Series(2, "Idle", [Available(0), Available(0)], Available(0));
        var result = Result(buckets, [silent, idle], []) with
        {
            Classification =
            [
                new MeterClassification(1, "Silent", Entry(1, MeterTotalsClass.Use, MeterTotalsReason.ConsumptionRoot, measure: TotalsMeasure.Use)),
                new MeterClassification(2, "Idle", Entry(2, MeterTotalsClass.Breakdown, MeterTotalsReason.ContainedByLink, parents: [1])),
            ],
        };

        var rows = MeterListRows.Build([Facts(2, "Idle"), Facts(1, "Silent"), Facts(3, "Added later")], result);

        Assert.Equal(["Added later", "Idle", "Silent"], rows.Select(r => r.Meter.Name));
        var silentRow = rows.Single(r => r.Meter.Id == 1);
        Assert.Equal("No data", silentRow.ValueText);
        Assert.False(silentRow.HasValue);
        Assert.Equal("No data covers this period", silentRow.QualityDetail);

        var idleRow = rows.Single(r => r.Meter.Id == 2);
        Assert.Equal("0 kWh", idleRow.ValueText);
        Assert.True(idleRow.HasValue);
        Assert.Equal("Part of Silent: shown, but never added on top.", idleRow.Membership!.Detail);

        // A meter the read did not cover has no figure at all, not a zero.
        var later = rows.Single(r => r.Meter.Id == 3);
        Assert.Equal(Format.Unknown, later.ValueText);
        Assert.Null(later.Membership);
    });

    [Fact]
    public void Meter_rows_search_names_serials_types_modes_and_membership() => In("en", () =>
    {
        var row = new MeterListRow(Facts(1, "Zähler Haus") with { SerialNumber = "SN-77", Location = "Keller" }, null,
            new MeterMembership(MeterTotalsClass.Breakdown, "Breakdown of a counted meter", string.Empty), null);

        Assert.True(MeterListRows.Matches(row, null));
        Assert.True(MeterListRows.Matches(row, "  haus "));
        Assert.True(MeterListRows.Matches(row, "sn-7"));
        Assert.True(MeterListRows.Matches(row, "keller"));
        Assert.True(MeterListRows.Matches(row, "strom"));
        Assert.True(MeterListRows.Matches(row, "cumulative"));
        Assert.True(MeterListRows.Matches(row, "breakdown"));
        Assert.False(MeterListRows.Matches(row, "wasser"));
    });

    [Fact]
    public void Quick_entry_is_a_reading_a_tank_level_or_nothing_for_a_calculation()
    {
        Assert.Equal(MeterLinks.QuickEntry(1, MeterMode.CumulativeCounter), MeterListRows.QuickEntry(Facts(1, "A"))!.Value.Href);
        Assert.True(MeterListRows.QuickEntry(Facts(2, "Tank") with { Mode = MeterMode.ConsumableBalance })!.Value.IsTank);
        Assert.Null(MeterListRows.QuickEntry(Facts(3, "Sum") with { Mode = MeterMode.Virtual }));
    }

    // ------------------------------------------------------------------------------------------------ changes

    [Fact]
    public void Largest_changes_use_matched_values_and_skip_what_is_not_comparable()
    {
        var matched = new MatchedCoverageResult(
            new MatchedRange(Now, Now, D(2025, 1, 1), D(2025, 1, 31)),
            new MatchedRange(Now, Now, D(2024, 1, 1), D(2024, 1, 31)),
            [new MatchedPiece(new MatchedRange(Now, Now, D(2025, 1, 1), D(2025, 1, 31)), new MatchedRange(Now, Now, D(2024, 1, 1), D(2024, 1, 31)))]);
        AnalysisSeries With(int id, double current, double previous) =>
            Series(id, $"M{id}", [Available(current)]) with
            {
                Comparison = new SeriesComparison([Available(previous)], Available(previous), matched, current, previous, Change.Between(current, previous)),
            };

        var notComparable = Series(9, "Not comparable", [Available(5)]) with
        {
            Comparison = new SeriesComparison([Missing()], Missing(), MatchedCoverageResult.NotComparable, null, null, Change.Unavailable),
        };

        var changes = MeterChanges.Largest([With(1, 100, 90), With(2, 50, 150), With(3, 10, 10), notComparable], 2);

        Assert.Equal([2, 1], changes.Select(c => c.Series.MeterId!.Value));
        Assert.Equal(-100, changes[0].Change.Absolute!.Value, 6);
        Assert.Equal(50, changes[0].Current, 6);
        Assert.Equal(150, changes[0].Previous, 6);
    }

    // ------------------------------------------------------------------------------------------------ flow words

    [Fact]
    public void The_flow_table_words_every_ribbon_and_every_meter_it_does_not_draw() => In("en", () =>
    {
        var graph = new FlowGraph(1, "Strom", "kWh", 100, [
            new FlowNode("m1", "Haus", 100, 0, null, false, 1),
            new FlowNode("m2", "Auto", 30, 1, null, false, 2),
            new FlowNode("other1", "Haus", 70, 1, null, true, null),
        ], [
            new FlowLink("m1", "m2", 30),
            new FlowLink("m1", "other1", 70),
            new FlowLink("m4", "m9", 10) { IsCalculated = true },
            new FlowLink("m3", "m1", 5) { IsEstimated = true },
            new FlowLink("m3", "m2", 5) { IsEstimated = true, IsCapped = true },
        ]);

        Assert.Equal("Other (Haus)", FlowText.NodeName(graph, "other1"));
        Assert.Equal("Measured part", FlowText.EdgeKind(graph, graph.Links[0]));
        Assert.Equal("Not measured by a meter below it", FlowText.EdgeKind(graph, graph.Links[1]));
        Assert.Equal("Input of a calculated sum", FlowText.EdgeKind(graph, graph.Links[2]));
        Assert.StartsWith("Estimated share", FlowText.EdgeKind(graph, graph.Links[3]), StringComparison.Ordinal);
        Assert.StartsWith("Estimated, capped", FlowText.EdgeKind(graph, graph.Links[4]), StringComparison.Ordinal);

        var water = new FlowMeter(7, "Water", 7, BucketStatus.Available, ValueIssue.None, QuantityKind.Consumption, "m³", SeriesBasis.Physical, false);
        var difference = new FlowMeter(8, "A − B", -50, BucketStatus.Available, ValueIssue.None, QuantityKind.Net, "kWh", SeriesBasis.Virtual, false);
        var silent = new FlowMeter(9, "Silent", null, BucketStatus.Missing, ValueIssue.NoCoverage, QuantityKind.Consumption, "kWh", SeriesBasis.Physical, false);
        Assert.Equal("Not drawn: measured in m³", FlowText.NotDrawnReason(graph, water));
        Assert.Equal("Not drawn: a calculation that is not a plain sum", FlowText.NotDrawnReason(graph, difference));
        Assert.Null(FlowText.NotDrawnReason(graph, water with { InDiagram = true }));

        // Signed stays signed, and a meter without a number says so instead of "0".
        Assert.Equal("-50 kWh", FlowText.MeterValue(difference));
        Assert.Equal("No data", FlowText.MeterValue(silent));
    });

    // ------------------------------------------------------------------------------------------------ connection rules

    [Fact]
    public void A_connection_is_refused_into_itself_across_types_twice_or_around_a_loop()
    {
        var a = Link(1, "A");
        var b = Link(2, "B");
        var c = Link(3, "C");
        var foreign = Link(4, "Foreign") with { EnergyTypeId = 2 };
        (int, int)[] links = [(1, 2), (2, 3)];

        Assert.Equal(MeterLinkRefusal.SameMeter, MeterLinkRules.CheckAdd(a, a, links, 1, 1).Refusal);
        Assert.Equal(MeterLinkRefusal.UnknownMeter, MeterLinkRules.CheckAdd(a, null, links, 1, 99).Refusal);
        Assert.Equal(MeterLinkRefusal.OtherEnergyType, MeterLinkRules.CheckAdd(a, foreign, links, 1, 4).Refusal);
        Assert.Equal(MeterLinkRefusal.AlreadyLinked, MeterLinkRules.CheckAdd(a, b, links, 1, 2).Refusal);

        // C → A would close A → B → C → A: refused, with the existing path from A to C.
        var loop = MeterLinkRules.CheckAdd(c, a, links, 3, 1);
        Assert.Equal(MeterLinkRefusal.WouldCreateCycle, loop.Refusal);
        Assert.Equal([1, 2, 3], loop.Path);
        Assert.Equal(MeterLinkRefusal.WouldCreateCycle, MeterLinkRules.CheckAdd(b, a, links, 2, 1).Refusal);

        // A shortcut in the same direction is no loop.
        Assert.True(MeterLinkRules.CheckAdd(a, c, links, 1, 3).IsAllowed);
    }

    [Fact]
    public void A_virtual_meter_calculated_from_its_links_keeps_them()
    {
        var source = Link(1, "Solar 1");
        var legacy = Link(9, "Legacy sum") with { Mode = MeterMode.Virtual, CalculatedFromLinks = true };
        var defined = Link(10, "Summe Solar") with { Mode = MeterMode.Virtual, ReferencedMeterIds = [1] };

        Assert.Equal(MeterLinkRefusal.CalculatedFromLinks, MeterLinkRules.CheckAdd(source, legacy, [], 1, 9).Refusal);
        Assert.Equal(MeterLinkRefusal.CalculatedFromLinks, MeterLinkRules.CheckRemove(legacy).Refusal);

        // A stored calculation is the formula's, never the links': those stay free to edit.
        Assert.True(MeterLinkRules.CheckAdd(source, defined, [], 1, 10).IsAllowed);
        Assert.True(MeterLinkRules.CheckRemove(defined).IsAllowed);

        var topology = new MeterLinkTopology(1, [source, defined], [new MeterLinkEntry(5, 1, 10)], new Dictionary<int, MeterLinkMeter>(), [(1, 10)]);
        Assert.True(topology.MirrorsCalculation(topology.Links[0]));
    }

    [Fact]
    public void A_refusal_is_worded_with_the_meters_named() => In("en", () =>
    {
        var names = new Dictionary<int, string> { [1] = "Haus", [2] = "Auto", [3] = "Wallbox" };
        var loop = new MeterLinkCheck(MeterLinkRefusal.WouldCreateCycle, [1, 2, 3]);

        Assert.Equal("This would make a loop: Haus → Auto → Wallbox → Haus.", FlowText.Refusal(loop, id => names[id], 1));
        Assert.Contains("Wallbox is calculated from its connections", FlowText.Refusal(MeterLinkCheck.Refused(MeterLinkRefusal.CalculatedFromLinks), id => names[id], 3), StringComparison.Ordinal);
        Assert.Equal(string.Empty, FlowText.Refusal(MeterLinkCheck.Allowed, id => names[id], 1));
    });

    [Fact]
    public void Describing_a_meter_reads_whether_its_calculation_is_stored()
    {
        var legacy = new Meter { Id = 9, Name = "Legacy", EnergyTypeId = 1, Mode = MeterMode.Virtual, Unit = "kWh", Meta = "{}" };
        var defined = new Meter
        {
            Id = 10,
            Name = "Sum",
            EnergyTypeId = 1,
            Mode = MeterMode.Virtual,
            Unit = "kWh",
            Meta = MeterVault.Core.Analysis.Virtual.VirtualDefinitionJson.Write(
                "{}", new MeterVault.Core.Analysis.Virtual.VirtualDefinition("m4 + m5", QuantityKind.Generation, "kWh", MeterVault.Core.Analysis.Virtual.VirtualCostRule.None)),
        };
        var physical = new Meter { Id = 4, Name = "Solar 1", EnergyTypeId = 1, Mode = MeterMode.GenerationCounter, Unit = "kWh", Meta = "{}" };

        Assert.True(MeterLinkRules.Describe(legacy).CalculatedFromLinks);
        Assert.False(MeterLinkRules.Describe(defined).CalculatedFromLinks);
        Assert.Equal([4, 5], MeterLinkRules.Describe(defined).ReferencedMeterIds);
        Assert.False(MeterLinkRules.Describe(physical).CalculatedFromLinks);
    }

    // ------------------------------------------------------------------------------------------------ helpers

    private static AnalysisSeries Measure(TotalsMeasure measure, QuantityKind kind, IReadOnlyList<AnalysisBucket> buckets) =>
        new(SeriesKey.ForMeasure(1, measure, "kWh"), string.Empty, SeriesBasis.Measure, kind, "kWh",
            [.. buckets.Select(_ => Available(1))], Available(buckets.Count), IsAdditive: true);

    private static AnalysisResult Result(IReadOnlyList<AnalysisBucket> buckets, IReadOnlyList<AnalysisSeries> series, IReadOnlyList<AnalysisSeries> measures)
    {
        var period = Range(buckets[0].FirstDay, buckets[^1].EndDay.AddDays(-1));
        var plan = BucketPlanner.Plan(period, BucketSize.Month);
        return new AnalysisResult(new AnalysisRequest(AnalysisScope.ForEnergyType(1), period), plan, series, measures, ScopeAvailability.None, []);
    }

    private static MeterTotalsEntry Entry(
        int meterId, MeterTotalsClass @class, MeterTotalsReason reason, TotalsMeasure? measure = null, IReadOnlyList<int>? parents = null) =>
        new(meterId, 1, @class, reason, @class, measure, parents ?? [], [], null, null);

    private static MeterFacts Facts(int id, string name) =>
        new(id, name, 1, "Strom", MeterMode.CumulativeCounter, "kWh", IsActive: true, null, null, HasTank: false);

    private static MeterLinkMeter Link(int id, string name) => new(id, name, 1, MeterMode.CumulativeCounter, true, false, []);
}