Unify recommendations across shifts AND jobs

Recommendations only scored open shifts, but almost all roles — doctors especially — exist as
استخدام (jobs), not dated shifts, and the only shifts are a handful of nurse shifts. So a visitor
who prefers «پزشک» got nurse-shift recommendations (scored by city/freshness) because there were
no doctor shifts to surface.

Now the engine scores BOTH shifts and job openings: role/city/facility/pay/freshness apply to
each, behavioral affinities are derived from shift AND job interest events, and the merged top-N
is returned. Recommendation can now carry a Shift or a JobOpening; the card renders either
(job → /Jobs/Details with employment type + salary; shift → unchanged with hour-bar). Cold start
interleaves the freshest of both.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/JobsMedical.Web/Pages/Shared/_RecommendationCard.cshtml

@@ -1,6 +1,28 @@
 @model JobsMedical.Web.Services.Recommendation
 @{
-    var s = Model.Shift;
+    var isJob = Model.IsJob;
+    var role = isJob ? Model.Job!.Role?.Name : Model.Shift!.Role?.Name;
+    var fac = isJob ? Model.Job!.Facility : Model.Shift!.Facility;
+    var gender = isJob ? Model.Job!.GenderRequirement : Model.Shift!.GenderRequirement;
+    var url = isJob ? $"/Jobs/Details/{Model.Job!.Id}" : $"/Shifts/Details/{Model.Shift!.Id}";
+    string empLabel(JobsMedical.Web.Models.EmploymentType t) => t switch
+    {
+        JobsMedical.Web.Models.EmploymentType.PartTime => "پاره‌وقت",
+        JobsMedical.Web.Models.EmploymentType.Contract => "قراردادی",
+        JobsMedical.Web.Models.EmploymentType.Plan => "طرح",
+        _ => "تمام‌وقت",
+    };
+}
+<a class="card card-pad shift-card" href="@url">
+    <div class="row" style="justify-content: space-between;">
+        <span class="facility">@(role ?? (isJob ? "استخدام" : "شیفت"))</span>
+        @if (isJob)
+        {
+            <span class="badge badge-job">استخدام</span>
+        }
+        else
+        {
+            var s = Model.Shift!;
             var (badgeClass, typeLabel) = s.ShiftType switch
             {
                 ShiftType.Day => ("badge-day", "صبح"),
@@ -8,25 +30,31 @@
                 ShiftType.Night => ("badge-night", "شب"),
                 _ => ("badge-oncall", "آنکال"),
             };
-}
-<a class="card card-pad shift-card" asp-page="/Shifts/Details" asp-route-id="@s.Id">
-    <div class="row" style="justify-content: space-between;">
-        <span class="facility">@(s.Role?.Name ?? "شیفت")</span>
             <span class="badge @badgeClass">@typeLabel</span>
+        }
     </div>
     <div class="row">
-        @if (s.GenderRequirement != Gender.Any)
+        @if (gender != Gender.Any)
         {
-            <span class="badge badge-gender">@JalaliDate.GenderLabel(s.GenderRequirement)</span>
+            <span class="badge badge-gender">@JalaliDate.GenderLabel(gender)</span>
         }
-        @if (JobsMedical.Web.Services.SeoJsonLd.HasRealEmployer(s.Facility))
+        @if (JobsMedical.Web.Services.SeoJsonLd.HasRealEmployer(fac))
         {
-            <span>🏥 @s.Facility?.Name</span>
+            <span>🏥 @fac?.Name</span>
         }
-        <span>📍 @s.Facility?.City?.Name</span>
+        <span>📍 @fac?.City?.Name</span>
     </div>
+
+    @if (isJob)
+    {
+        <div class="row">💼 @empLabel(Model.Job!.EmploymentType)</div>
+    }
+    else
+    {
+        var s = Model.Shift!;
         <div class="row">📅 @JalaliDate.WeekDayName(s.Date)، @JalaliDate.ToLongDate(s.Date) — 🕐 @JalaliDate.Time(s.StartTime)</div>
         <partial name="_HourBar" model="s" />
+    }
 
     @* The "why" — what makes a pattern engine trustworthy: every pick is explained. *@
     <div class="rec-reasons">
@@ -37,7 +65,17 @@
     </div>
 
     <div class="foot">
-        <span class="pay">@JalaliDate.PayLabel(s.PayType, s.PayAmount, s.SharePercent)</span>
+        <span class="pay">
+            @if (isJob)
+            {
+                @(Model.Job!.SalaryMin is long m ? JalaliDate.ToPersianDigits(m.ToString("#,0")) + " تومان" : "توافقی")
+            }
+            else
+            {
+                var s = Model.Shift!;
+                @JalaliDate.PayLabel(s.PayType, s.PayAmount, s.SharePercent)
+            }
+        </span>
         <span class="btn btn-outline" style="padding: 6px 14px;">جزئیات</span>
     </div>
 </a>

src/JobsMedical.Web/Services/RecommendationService.cs

@@ -4,14 +4,19 @@ using Microsoft.EntityFrameworkCore;
 
 namespace JobsMedical.Web.Services;
 
-public record Recommendation(Shift Shift, double Score, List<string> Reasons);
+/// <summary>A recommended opportunity — either an open <see cref="Shift"/> or an open
+/// <see cref="JobOpening"/>. Exactly one of the two is set.</summary>
+public record Recommendation(double Score, List<string> Reasons, Shift? Shift = null, JobOpening? Job = null)
+{
+    public bool IsJob => Job is not null;
+}
 
 /// <summary>
-/// Stage 1 of the recommendation engine: a transparent, rule-based pattern engine.
-/// It scores open shifts against a visitor's explicit preferences AND their recent behavior
-/// (which roles/facilities/shift-types they keep engaging with), and returns the top matches
-/// each with a human-readable reason. No ML/AI infra required — works from the first visit,
-/// and every result is explainable. Behavioral data logged now feeds the ML stages later.
+/// Stage 1 of the recommendation engine: a transparent, rule-based pattern engine. It scores open
+/// opportunities — BOTH shifts AND job openings — against a visitor's explicit preferences and their
+/// recent behavior, and returns the top matches each with a human-readable reason. Covering jobs (not
+/// just shifts) matters because most roles — especially doctors — exist as استخدام, not dated shifts;
+/// a shift-only feed would only ever recommend the handful of (mostly nurse) shifts.
 /// </summary>
 public class RecommendationService
 {
@@ -24,7 +29,6 @@ public class RecommendationService
         _interest = interest;
     }
 
-    // Tunable weights — the whole point of a pattern engine is that these are legible.
     private const double WRolePref = 40, WRoleBehavior = 15;
     private const double WCityPref = 20;
     private const double WShiftTypePref = 15, WShiftTypeBehavior = 8;
@@ -36,64 +40,69 @@ public class RecommendationService
     public async Task<List<Recommendation>> GetForVisitorAsync(int take = 6)
     {
         var today = DateOnly.FromDateTime(DateTime.UtcNow);
+        var jobCutoff = Scraping.ListingPolicy.JobCutoffUtc;
         var prefs = await _interest.GetPreferencesAsync();
         var events = await _interest.RecentEventsAsync(150);
 
-        var candidates = await _db.Shifts
-            .Include(s => s.Facility).ThenInclude(f => f.City)
-            .Include(s => s.Role)
-            .Where(s => s.Status == ShiftStatus.Open && s.Date >= today)
-            .ToListAsync();
+        var shifts = await _db.Shifts
+            .Include(s => s.Facility).ThenInclude(f => f.City).Include(s => s.Role)
+            .Where(s => s.Status == ShiftStatus.Open && s.Date >= today).ToListAsync();
+        var jobs = await _db.JobOpenings
+            .Include(j => j.Facility).ThenInclude(f => f.City).Include(j => j.Role)
+            .Where(j => j.Status == ShiftStatus.Open && j.CreatedAt >= jobCutoff).ToListAsync();
 
-        // Cold start: no preferences and no behavior → just show the freshest opportunities.
+        // Cold start: freshest of both, interleaved (jobs lead — that's where the volume/roles are).
         if (prefs is null && events.Count == 0)
         {
-            return candidates
-                .OrderBy(s => s.Date).ThenBy(s => s.StartTime)
-                .Take(take)
-                .Select(s => new Recommendation(s, 0, new() { "جدیدترین فرصت‌ها" }))
-                .ToList();
+            var cj = jobs.OrderByDescending(j => j.CreatedAt)
+                .Select(j => new Recommendation(0, new List<string> { "جدیدترین فرصت‌ها" }, Job: j));
+            var cs = shifts.OrderBy(s => s.Date).ThenBy(s => s.StartTime)
+                .Select(s => new Recommendation(0, new List<string> { "جدیدترین فرصت‌ها" }, Shift: s));
+            return Interleave(cj, cs).Take(take).ToList();
         }
 
-        // Derive behavioral affinities from the event log (shift events only — jobs are separate).
-        var shiftEvents = events.Where(e => e.ShiftId is not null).ToList();
-        var eventShiftIds = shiftEvents.Select(e => e.ShiftId!.Value).Distinct().ToList();
-        var eventShifts = candidates.Where(s => eventShiftIds.Contains(s.Id))
-            .Concat(await _db.Shifts.Include(s => s.Role)
-                .Where(s => eventShiftIds.Contains(s.Id)).ToListAsync())
-            .DistinctBy(s => s.Id)
-            .ToDictionary(s => s.Id);
+        // Behavioral affinities — derived from BOTH shift and job events (role/facility span both;
+        // shift-type is shift-only). Look up each engaged item's role/facility/type once.
+        var positive = new[] { InterestEventType.View, InterestEventType.Click, InterestEventType.Save, InterestEventType.Apply };
+        var negative = new[] { InterestEventType.Dismiss, InterestEventType.HideFacility };
 
-        var positive = new[] { InterestEventType.View, InterestEventType.Click,
-                               InterestEventType.Save, InterestEventType.Apply };
+        var sIds = events.Where(e => e.ShiftId is not null).Select(e => e.ShiftId!.Value).Distinct().ToList();
+        var jIds = events.Where(e => e.JobOpeningId is not null).Select(e => e.JobOpeningId!.Value).Distinct().ToList();
+        var sMeta = (await _db.Shifts.Where(s => sIds.Contains(s.Id))
+            .Select(s => new { s.Id, s.RoleId, s.FacilityId, s.ShiftType }).ToListAsync()).ToDictionary(x => x.Id);
+        var jMeta = (await _db.JobOpenings.Where(j => jIds.Contains(j.Id))
+            .Select(j => new { j.Id, j.RoleId, j.FacilityId }).ToListAsync()).ToDictionary(x => x.Id);
 
-        var roleAffinity = TopBy(shiftEvents, positive, eventShifts, s => s.RoleId);
-        var shiftTypeAffinity = TopBy(shiftEvents, positive, eventShifts, s => (int)s.ShiftType);
-        var facilityAffinity = TopBy(shiftEvents, positive, eventShifts, s => s.FacilityId);
+        var roleCount = new Dictionary<int, int>();
+        var facCount = new Dictionary<int, int>();
+        var stCount = new Dictionary<int, int>();
+        var dismissedFacilities = new HashSet<int>();
+        foreach (var e in events)
+        {
+            int roleId, facId; int? st = null;
+            if (e.ShiftId is int si && sMeta.TryGetValue(si, out var sm)) { roleId = sm.RoleId; facId = sm.FacilityId; st = (int)sm.ShiftType; }
+            else if (e.JobOpeningId is int ji && jMeta.TryGetValue(ji, out var jm)) { roleId = jm.RoleId; facId = jm.FacilityId; }
+            else continue;
 
-        var dismissedFacilities = shiftEvents
-            .Where(e => e.EventType is InterestEventType.Dismiss or InterestEventType.HideFacility)
-            .Select(e => eventShifts.TryGetValue(e.ShiftId!.Value, out var s) ? s.FacilityId : 0)
-            .Where(id => id != 0).ToHashSet();
+            if (positive.Contains(e.EventType))
+            {
+                Bump(roleCount, roleId); Bump(facCount, facId);
+                if (st is int t) Bump(stCount, t);
+            }
+            else if (negative.Contains(e.EventType)) dismissedFacilities.Add(facId);
+        }
+        var roleAffinity = Top3(roleCount);
+        var facilityAffinity = Top3(facCount);
+        var shiftTypeAffinity = Top3(stCount);
 
         var results = new List<Recommendation>();
-        foreach (var s in candidates)
+
+        foreach (var s in shifts)
         {
-            // Skip listings whose gender requirement conflicts with the person's gender.
-            if (prefs?.Gender is Gender pg && pg != Gender.Any
-                && s.GenderRequirement != Gender.Any && s.GenderRequirement != pg)
-                continue;
-
-            double score = 0;
-            var reasons = new List<string>();
-
-            if (prefs?.RoleId is int pr && pr == s.RoleId)
-            { score += WRolePref; reasons.Add($"متناسب با نقش مورد علاقه شما ({s.Role.Name})"); }
-            else if (roleAffinity.Contains(s.RoleId))
-            { score += WRoleBehavior; reasons.Add($"چون به فرصت‌های «{s.Role.Name}» علاقه نشان دادی"); }
-
-            if (prefs?.CityId is int pc && pc == s.Facility.CityId)
-            { score += WCityPref; reasons.Add($"در شهر مورد علاقه شما ({s.Facility.City.Name})"); }
+            if (GenderConflicts(prefs, s.GenderRequirement)) continue;
+            double score = 0; var reasons = new List<string>();
+            ScoreCommon(ref score, reasons, prefs, s.RoleId, s.Role?.Name, s.Facility.CityId, s.Facility.City?.Name,
+                s.FacilityId, s.Facility?.Name, roleAffinity, facilityAffinity, dismissedFacilities);
 
             if (prefs?.PreferredShiftType is ShiftType pst && pst == s.ShiftType)
             { score += WShiftTypePref; reasons.Add($"نوع شیفت دلخواه شما ({ShiftTypeLabel(s.ShiftType)})"); }
@@ -103,41 +112,71 @@ public class RecommendationService
             if (prefs?.MinPay is long min && s.PayAmount is long pay && pay >= min)
             { score += WPayMeetsExpectation; reasons.Add("حقوق بالاتر از حد انتظار شما"); }
 
-            if (facilityAffinity.Contains(s.FacilityId))
-            { score += WFacilityAffinity; reasons.Add($"از مرکزی که قبلاً به آن علاقه نشان دادی ({s.Facility.Name})"); }
-
-            if (dismissedFacilities.Contains(s.FacilityId))
-                score -= PenaltyDismissedFacility;
-
-            // Sooner shifts and freshly posted ones get a small nudge.
             var daysOut = s.Date.DayNumber - today.DayNumber;
             if (daysOut <= 3) score += WSoon;
             if ((DateTime.UtcNow - s.CreatedAt).TotalDays <= 2) score += WFreshness;
 
             if (reasons.Count == 0) reasons.Add("پیشنهاد بر اساس فعالیت شما");
-            results.Add(new Recommendation(s, score, reasons));
+            results.Add(new Recommendation(score, reasons, Shift: s));
+        }
+
+        foreach (var j in jobs)
+        {
+            if (GenderConflicts(prefs, j.GenderRequirement)) continue;
+            double score = 0; var reasons = new List<string>();
+            ScoreCommon(ref score, reasons, prefs, j.RoleId, j.Role?.Name, j.Facility.CityId, j.Facility.City?.Name,
+                j.FacilityId, j.Facility?.Name, roleAffinity, facilityAffinity, dismissedFacilities);
+
+            if (prefs?.MinPay is long min && j.SalaryMin is long pay && pay >= min)
+            { score += WPayMeetsExpectation; reasons.Add("حقوق بالاتر از حد انتظار شما"); }
+            if ((DateTime.UtcNow - j.CreatedAt).TotalDays <= 2) score += WFreshness;
+
+            if (reasons.Count == 0) reasons.Add("پیشنهاد بر اساس فعالیت شما");
+            results.Add(new Recommendation(score, reasons, Job: j));
         }
 
         return results
             .Where(r => r.Score > 0)
-            .OrderByDescending(r => r.Score).ThenBy(r => r.Shift.Date)
+            .OrderByDescending(r => r.Score)
             .Take(take)
             .ToList();
     }
 
-    /// <summary>Keys the visitor engaged with most (positive events), top 3.</summary>
-    private static HashSet<int> TopBy(
-        List<InterestEvent> events, InterestEventType[] positive,
-        Dictionary<int, Shift> shiftById, Func<Shift, int> key)
+    /// <summary>Role + city + facility scoring shared by shifts and jobs.</summary>
+    private static void ScoreCommon(ref double score, List<string> reasons, UserPreferences? prefs,
+        int roleId, string? roleName, int cityId, string? cityName, int facilityId, string? facilityName,
+        HashSet<int> roleAffinity, HashSet<int> facilityAffinity, HashSet<int> dismissedFacilities)
     {
-        return events
-            .Where(e => e.ShiftId is not null && positive.Contains(e.EventType)
-                        && shiftById.ContainsKey(e.ShiftId.Value))
-            .GroupBy(e => key(shiftById[e.ShiftId!.Value]))
-            .OrderByDescending(g => g.Count())
-            .Take(3)
-            .Select(g => g.Key)
-            .ToHashSet();
+        if (prefs?.RoleId is int pr && pr == roleId)
+        { score += WRolePref; reasons.Add($"متناسب با نقش مورد علاقه شما ({roleName})"); }
+        else if (roleAffinity.Contains(roleId))
+        { score += WRoleBehavior; reasons.Add($"چون به فرصت‌های «{roleName}» علاقه نشان دادی"); }
+
+        if (prefs?.CityId is int pc && pc == cityId)
+        { score += WCityPref; reasons.Add($"در شهر مورد علاقه شما ({cityName})"); }
+
+        if (facilityAffinity.Contains(facilityId))
+        { score += WFacilityAffinity; reasons.Add($"از مرکزی که قبلاً به آن علاقه نشان دادی ({facilityName})"); }
+
+        if (dismissedFacilities.Contains(facilityId)) score -= PenaltyDismissedFacility;
+    }
+
+    private static bool GenderConflicts(UserPreferences? prefs, Gender req)
+        => prefs?.Gender is Gender pg && pg != Gender.Any && req != Gender.Any && req != pg;
+
+    private static void Bump(Dictionary<int, int> d, int k) => d[k] = d.GetValueOrDefault(k) + 1;
+    private static HashSet<int> Top3(Dictionary<int, int> d) => d.OrderByDescending(k => k.Value).Take(3).Select(k => k.Key).ToHashSet();
+
+    private static IEnumerable<Recommendation> Interleave(IEnumerable<Recommendation> a, IEnumerable<Recommendation> b)
+    {
+        using var ea = a.GetEnumerator();
+        using var eb = b.GetEnumerator();
+        bool ha = ea.MoveNext(), hb = eb.MoveNext();
+        while (ha || hb)
+        {
+            if (ha) { yield return ea.Current; ha = ea.MoveNext(); }
+            if (hb) { yield return eb.Current; hb = eb.MoveNext(); }
+        }
     }
 
     private static string ShiftTypeLabel(ShiftType t) => t switch