0.6.8

小黑板数据持久化。
2026-06-22 09:14:25 +08:00 · 2026-03-19 16:27:16 +08:00
parent b3a74aa072
commit cb86ca10e7
27 changed files with 1216 additions and 52 deletions
--- a/LanMountainDesktop/Services/AppDatabaseService.cs
+++ b/LanMountainDesktop/Services/AppDatabaseService.cs
@@ -29,6 +29,16 @@ public sealed class AppDatabaseService
        _databasePath = Path.Combine(dataDirectory, "app.db");
    }

+    public AppDatabaseService(string databasePath)
+    {
+        if (string.IsNullOrWhiteSpace(databasePath))
+        {
+            throw new ArgumentException("Database path cannot be null or whitespace.", nameof(databasePath));
+        }
+
+        _databasePath = databasePath;
+    }
+
    public SqliteConnection OpenConnection()
    {
        var directory = Path.GetDirectoryName(_databasePath);
--- a/LanMountainDesktop/Services/ComponentSettingsService.cs
+++ b/LanMountainDesktop/Services/ComponentSettingsService.cs
@@ -106,6 +106,8 @@ public sealed class ComponentSettingsService : IComponentInstanceSettingsStore

    public void DeleteForComponent(string componentId, string? placementId)
    {
+        _ = new WhiteboardNotePersistenceService().DeleteNote(componentId, placementId);
+
        if (_settingsService is not null)
        {
            _settingsService.SaveSnapshot(
--- a/LanMountainDesktop/Services/DesktopComponentEditorRegistryFactory.cs
+++ b/LanMountainDesktop/Services/DesktopComponentEditorRegistryFactory.cs
@@ -75,6 +75,12 @@ public static class DesktopComponentEditorRegistryFactory
            [BuiltInComponentIds.DesktopRemovableStorage] = new(
                BuiltInComponentIds.DesktopRemovableStorage,
                context => new RemovableStorageComponentEditor(context)),
+            [BuiltInComponentIds.DesktopWhiteboard] = new(
+                BuiltInComponentIds.DesktopWhiteboard,
+                context => new WhiteboardComponentEditor(context)),
+            [BuiltInComponentIds.DesktopBlackboardLandscape] = new(
+                BuiltInComponentIds.DesktopBlackboardLandscape,
+                context => new WhiteboardComponentEditor(context)),
            [BuiltInComponentIds.DesktopOfficeRecentDocuments] = new(
                BuiltInComponentIds.DesktopOfficeRecentDocuments,
                context => new OfficeRecentDocumentsComponentEditor(context)),
--- a/LanMountainDesktop/Services/IWhiteboardNotePersistenceService.cs
+++ b/LanMountainDesktop/Services/IWhiteboardNotePersistenceService.cs
@@ -0,0 +1,19 @@
+using System;
+using LanMountainDesktop.Models;
+
+namespace LanMountainDesktop.Services;
+
+public interface IWhiteboardNotePersistenceService
+{
+    WhiteboardNoteSnapshot LoadNote(string componentId, string? placementId, int retentionDays);
+
+    void SaveNote(string componentId, string? placementId, WhiteboardNoteSnapshot snapshot, int retentionDays);
+
+    bool DeleteNote(string componentId, string? placementId);
+
+    bool TryDeleteExpiredNote(string componentId, string? placementId, int retentionDays);
+
+    bool IsExpired(WhiteboardNoteSnapshot snapshot, int retentionDays, DateTimeOffset? now = null);
+
+    DateTimeOffset? GetExpirationUtc(WhiteboardNoteSnapshot snapshot, int retentionDays);
+}
--- a/LanMountainDesktop/Services/WhiteboardNotePersistenceService.cs
+++ b/LanMountainDesktop/Services/WhiteboardNotePersistenceService.cs
@@ -0,0 +1,338 @@
+using System;
+using System.Text.Json;
+using LanMountainDesktop.Models;
+using Microsoft.Data.Sqlite;
+
+namespace LanMountainDesktop.Services;
+
+public sealed class WhiteboardNotePersistenceService : IWhiteboardNotePersistenceService
+{
+    private const int DefaultCleanupBatchSize = 256;
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        PropertyNameCaseInsensitive = true
+    };
+
+    private readonly object _schemaSyncRoot = new();
+    private readonly AppDatabaseService _databaseService;
+    private bool _schemaInitialized;
+
+    public WhiteboardNotePersistenceService(AppDatabaseService? databaseService = null)
+    {
+        _databaseService = databaseService ?? AppDatabaseServiceFactory.CreateDefault();
+    }
+
+    public WhiteboardNoteSnapshot LoadNote(string componentId, string? placementId, int retentionDays)
+    {
+        if (!TryNormalizeKeys(componentId, placementId, out var normalizedComponentId, out var normalizedPlacementId))
+        {
+            return new WhiteboardNoteSnapshot();
+        }
+
+        try
+        {
+            using var connection = OpenConnection();
+            DeleteExpiredInternal(
+                connection,
+                normalizedComponentId,
+                normalizedPlacementId,
+                WhiteboardNoteRetentionPolicy.NormalizeDays(retentionDays),
+                DateTimeOffset.UtcNow);
+
+            using var command = connection.CreateCommand();
+            command.CommandText = """
+                SELECT note_json, saved_at_utc_ms
+                FROM whiteboard_notes
+                WHERE component_id = $componentId
+                  AND placement_id = $placementId
+                LIMIT 1;
+                """;
+            command.Parameters.AddWithValue("$componentId", normalizedComponentId);
+            command.Parameters.AddWithValue("$placementId", normalizedPlacementId);
+
+            using var reader = command.ExecuteReader();
+            if (!reader.Read() || reader.IsDBNull(0))
+            {
+                return new WhiteboardNoteSnapshot();
+            }
+
+            var json = reader.GetString(0);
+            if (string.IsNullOrWhiteSpace(json))
+            {
+                return new WhiteboardNoteSnapshot();
+            }
+
+            var snapshot = JsonSerializer.Deserialize<WhiteboardNoteSnapshot>(json, JsonOptions) ?? new WhiteboardNoteSnapshot();
+            if (!reader.IsDBNull(1))
+            {
+                snapshot.SavedUtc = DateTimeOffset.FromUnixTimeMilliseconds(reader.GetInt64(1));
+            }
+
+            if (IsExpired(snapshot, retentionDays))
+            {
+                DeleteNote(normalizedComponentId, normalizedPlacementId);
+                return new WhiteboardNoteSnapshot();
+            }
+
+            return snapshot.Clone();
+        }
+        catch
+        {
+            return new WhiteboardNoteSnapshot();
+        }
+    }
+
+    public void SaveNote(string componentId, string? placementId, WhiteboardNoteSnapshot snapshot, int retentionDays)
+    {
+        if (!TryNormalizeKeys(componentId, placementId, out var normalizedComponentId, out var normalizedPlacementId))
+        {
+            return;
+        }
+
+        try
+        {
+            var nowUtc = DateTimeOffset.UtcNow;
+            var persistedSnapshot = snapshot?.Clone() ?? new WhiteboardNoteSnapshot();
+            persistedSnapshot.SavedUtc = nowUtc;
+            var expiresUtc = GetExpirationUtc(persistedSnapshot, retentionDays) ?? nowUtc.AddDays(WhiteboardNoteRetentionPolicy.DefaultDays);
+            var json = JsonSerializer.Serialize(persistedSnapshot, JsonOptions);
+
+            using var connection = OpenConnection();
+            using var command = connection.CreateCommand();
+            command.CommandText = """
+                INSERT INTO whiteboard_notes(
+                    component_id,
+                    placement_id,
+                    note_json,
+                    saved_at_utc_ms,
+                    expires_at_utc_ms,
+                    updated_at_utc_ms)
+                VALUES(
+                    $componentId,
+                    $placementId,
+                    $noteJson,
+                    $savedAtUtcMs,
+                    $expiresAtUtcMs,
+                    $updatedAtUtcMs)
+                ON CONFLICT(component_id, placement_id) DO UPDATE SET
+                    note_json = excluded.note_json,
+                    saved_at_utc_ms = excluded.saved_at_utc_ms,
+                    expires_at_utc_ms = excluded.expires_at_utc_ms,
+                    updated_at_utc_ms = excluded.updated_at_utc_ms;
+                """;
+            command.Parameters.AddWithValue("$componentId", normalizedComponentId);
+            command.Parameters.AddWithValue("$placementId", normalizedPlacementId);
+            command.Parameters.AddWithValue("$noteJson", json);
+            command.Parameters.AddWithValue("$savedAtUtcMs", persistedSnapshot.SavedUtc.ToUnixTimeMilliseconds());
+            command.Parameters.AddWithValue("$expiresAtUtcMs", expiresUtc.ToUnixTimeMilliseconds());
+            command.Parameters.AddWithValue("$updatedAtUtcMs", nowUtc.ToUnixTimeMilliseconds());
+            command.ExecuteNonQuery();
+        }
+        catch
+        {
+            // Keep whiteboard usable even when persistence is unavailable.
+        }
+    }
+
+    public bool DeleteNote(string componentId, string? placementId)
+    {
+        if (!TryNormalizeKeys(componentId, placementId, out var normalizedComponentId, out var normalizedPlacementId))
+        {
+            return false;
+        }
+
+        try
+        {
+            using var connection = OpenConnection();
+            using var command = connection.CreateCommand();
+            command.CommandText = """
+                DELETE FROM whiteboard_notes
+                WHERE component_id = $componentId
+                  AND placement_id = $placementId;
+                """;
+            command.Parameters.AddWithValue("$componentId", normalizedComponentId);
+            command.Parameters.AddWithValue("$placementId", normalizedPlacementId);
+            return command.ExecuteNonQuery() > 0;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    public bool TryDeleteExpiredNote(string componentId, string? placementId, int retentionDays)
+    {
+        if (!TryNormalizeKeys(componentId, placementId, out var normalizedComponentId, out var normalizedPlacementId))
+        {
+            return false;
+        }
+
+        try
+        {
+            using var connection = OpenConnection();
+            return DeleteExpiredInternal(
+                connection,
+                normalizedComponentId,
+                normalizedPlacementId,
+                WhiteboardNoteRetentionPolicy.NormalizeDays(retentionDays),
+                DateTimeOffset.UtcNow);
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
+    public int DeleteExpiredNotesBatch(int batchSize = DefaultCleanupBatchSize, DateTimeOffset? now = null)
+    {
+        try
+        {
+            using var connection = OpenConnection();
+            using var command = connection.CreateCommand();
+            command.CommandText = """
+                DELETE FROM whiteboard_notes
+                WHERE rowid IN (
+                    SELECT rowid
+                    FROM whiteboard_notes
+                    WHERE expires_at_utc_ms <= $nowUtcMs
+                    ORDER BY expires_at_utc_ms ASC
+                    LIMIT $batchSize
+                );
+                """;
+            command.Parameters.AddWithValue("$nowUtcMs", (now ?? DateTimeOffset.UtcNow).ToUnixTimeMilliseconds());
+            command.Parameters.AddWithValue("$batchSize", NormalizeBatchSize(batchSize));
+            return command.ExecuteNonQuery();
+        }
+        catch
+        {
+            return 0;
+        }
+    }
+
+    public bool IsExpired(WhiteboardNoteSnapshot snapshot, int retentionDays, DateTimeOffset? now = null)
+    {
+        if (snapshot is null)
+        {
+            return false;
+        }
+
+        var expirationUtc = GetExpirationUtc(snapshot, retentionDays);
+        if (!expirationUtc.HasValue)
+        {
+            return false;
+        }
+
+        return expirationUtc.Value <= (now ?? DateTimeOffset.UtcNow);
+    }
+
+    public DateTimeOffset? GetExpirationUtc(WhiteboardNoteSnapshot snapshot, int retentionDays)
+    {
+        if (snapshot is null || snapshot.SavedUtc == default)
+        {
+            return null;
+        }
+
+        return snapshot.SavedUtc.AddDays(WhiteboardNoteRetentionPolicy.NormalizeDays(retentionDays));
+    }
+
+    private SqliteConnection OpenConnection()
+    {
+        var connection = _databaseService.OpenConnection();
+        EnsureSchema(connection);
+        return connection;
+    }
+
+    private void EnsureSchema(SqliteConnection connection)
+    {
+        if (_schemaInitialized)
+        {
+            return;
+        }
+
+        lock (_schemaSyncRoot)
+        {
+            if (_schemaInitialized)
+            {
+                return;
+            }
+
+            using var command = connection.CreateCommand();
+            command.CommandText = """
+                CREATE TABLE IF NOT EXISTS whiteboard_notes (
+                    component_id TEXT NOT NULL,
+                    placement_id TEXT NOT NULL,
+                    note_json TEXT NOT NULL,
+                    saved_at_utc_ms INTEGER NOT NULL,
+                    expires_at_utc_ms INTEGER NOT NULL,
+                    updated_at_utc_ms INTEGER NOT NULL,
+                    PRIMARY KEY (component_id, placement_id)
+                );
+
+                CREATE INDEX IF NOT EXISTS idx_whiteboard_notes_expires_at
+                    ON whiteboard_notes(expires_at_utc_ms);
+                """;
+            command.ExecuteNonQuery();
+            _schemaInitialized = true;
+        }
+    }
+
+    private static bool DeleteExpiredInternal(
+        SqliteConnection connection,
+        string componentId,
+        string placementId,
+        int retentionDays,
+        DateTimeOffset nowUtc)
+    {
+        using var selectCommand = connection.CreateCommand();
+        selectCommand.CommandText = """
+            SELECT saved_at_utc_ms
+            FROM whiteboard_notes
+            WHERE component_id = $componentId
+              AND placement_id = $placementId
+            LIMIT 1;
+            """;
+        selectCommand.Parameters.AddWithValue("$componentId", componentId);
+        selectCommand.Parameters.AddWithValue("$placementId", placementId);
+
+        var scalar = selectCommand.ExecuteScalar();
+        if (scalar is not long savedAtUtcMs)
+        {
+            return false;
+        }
+
+        var savedUtc = DateTimeOffset.FromUnixTimeMilliseconds(savedAtUtcMs);
+        var expiresUtc = savedUtc.AddDays(WhiteboardNoteRetentionPolicy.NormalizeDays(retentionDays));
+        if (expiresUtc > nowUtc)
+        {
+            return false;
+        }
+
+        using var deleteCommand = connection.CreateCommand();
+        deleteCommand.CommandText = """
+            DELETE FROM whiteboard_notes
+            WHERE component_id = $componentId
+              AND placement_id = $placementId;
+            """;
+        deleteCommand.Parameters.AddWithValue("$componentId", componentId);
+        deleteCommand.Parameters.AddWithValue("$placementId", placementId);
+        return deleteCommand.ExecuteNonQuery() > 0;
+    }
+
+    private static bool TryNormalizeKeys(
+        string componentId,
+        string? placementId,
+        out string normalizedComponentId,
+        out string normalizedPlacementId)
+    {
+        normalizedComponentId = componentId?.Trim() ?? string.Empty;
+        normalizedPlacementId = placementId?.Trim() ?? string.Empty;
+        return !string.IsNullOrWhiteSpace(normalizedComponentId);
+    }
+
+    private static int NormalizeBatchSize(int batchSize)
+    {
+        return batchSize <= 0
+            ? DefaultCleanupBatchSize
+            : Math.Clamp(batchSize, 1, 4096);
+    }
+}