Add init weapon scraper

BlueLaminate/BlueLaminate.Cli/WeaponSyncService.cs

@@ -0,0 +1,77 @@
+using BlueLaminate.EFCore.Data;
+using BlueLaminate.EFCore.Entities;
+using BlueLaminate.Scraper.Weapons;
+using Microsoft.EntityFrameworkCore;
+
+namespace BlueLaminate.Cli;
+
+/// <param name="Skipped">True when the monthly throttle suppressed the run.</param>
+/// <param name="LastRanAt">When the previous successful run happened, if any.</param>
+public sealed record WeaponSyncResult(
+    bool Skipped,
+    DateTimeOffset? LastRanAt,
+    int Scraped,
+    int Inserted,
+    int Updated);
+
+/// <summary>
+/// Fetches the CS2 weapon catalogue and upserts it into the database. The
+/// catalogue changes rarely, so a run is throttled to at most once a month
+/// unless explicitly forced.
+/// </summary>
+public sealed class WeaponSyncService
+{
+    public const string Source = "weapons";
+
+    private readonly SkinTrackerDbContext _db;
+    private readonly WeaponWikiScraper _scraper;
+
+    public WeaponSyncService(SkinTrackerDbContext db, WeaponWikiScraper scraper)
+    {
+        _db = db;
+        _scraper = scraper;
+    }
+
+    public async Task<WeaponSyncResult> SyncAsync(bool force = false, CancellationToken ct = default)
+    {
+        var now = DateTimeOffset.UtcNow;
+
+        var lastRanAt = await _db.ScrapeRuns
+            .Where(r => r.Source == Source)
+            .OrderByDescending(r => r.RanAt)
+            .Select(r => (DateTimeOffset?)r.RanAt)
+            .FirstOrDefaultAsync(ct);
+
+        if (!force && lastRanAt is { } last && last.AddMonths(1) > now)
+            return new WeaponSyncResult(Skipped: true, last, Scraped: 0, Inserted: 0, Updated: 0);
+
+        var scraped = await _scraper.ScrapeAsync(ct);
+
+        var existing = await _db.Weapons.ToDictionaryAsync(w => w.Name, ct);
+        var inserted = 0;
+        var updated = 0;
+
+        foreach (var s in scraped)
+        {
+            if (existing.TryGetValue(s.Name, out var weapon))
+            {
+                if (weapon.Type != s.Type || weapon.Team != s.Team)
+                {
+                    weapon.Type = s.Type;
+                    weapon.Team = s.Team;
+                    updated++;
+                }
+            }
+            else
+            {
+                _db.Weapons.Add(new Weapon { Name = s.Name, Type = s.Type, Team = s.Team });
+                inserted++;
+            }
+        }
+
+        _db.ScrapeRuns.Add(new ScrapeRun { Source = Source, RanAt = now, ItemCount = scraped.Count });
+        await _db.SaveChangesAsync(ct);
+
+        return new WeaponSyncResult(Skipped: false, lastRanAt, scraped.Count, inserted, updated);
+    }
+}