Add split payslip feature with team pay schedules

Enable selective payment of work logs and adjustments instead of
all-or-nothing. The preview modal now shows checkboxes on every item
(all checked by default) with dynamic net pay recalculation.

Teams can be configured with a pay frequency (weekly/fortnightly/monthly)
and anchor start date. When set, a "Split at Pay Date" button appears
that auto-unchecks items outside the current pay period.

Key changes:
- Team model: add pay_frequency and pay_start_date fields
- preview_payslip: return IDs, dates, and pay period info in JSON
- process_payment: accept optional selected_log_ids/selected_adj_ids
- Preview modal JS: checkboxes, recalcNetPay(), Split button, Pay Selected
- Backward compatible: existing Pay button still processes everything

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/admin.py

@@ -25,8 +25,9 @@ class WorkerAdmin(admin.ModelAdmin):
 
 @admin.register(Team)
 class TeamAdmin(admin.ModelAdmin):
-    list_display = ('name', 'supervisor', 'active')
+    list_display = ('name', 'supervisor', 'pay_frequency', 'pay_start_date', 'active')
-    list_filter = ('active', 'supervisor')
+    list_editable = ('pay_frequency', 'pay_start_date')
+    list_filter = ('active', 'supervisor', 'pay_frequency')
     search_fields = ('name',)
     filter_horizontal = ('workers',)
 

core/migrations/0005_team_pay_frequency_team_pay_start_date.py

@@ -0,0 +1,23 @@
+# Generated by Django 5.2.7 on 2026-03-24 18:10
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0004_add_loan_type_and_advance_repayment'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='team',
+            name='pay_frequency',
+            field=models.CharField(blank=True, choices=[('weekly', 'Weekly'), ('fortnightly', 'Fortnightly'), ('monthly', 'Monthly')], default='', max_length=15),
+        ),
+        migrations.AddField(
+            model_name='team',
+            name='pay_start_date',
+            field=models.DateField(blank=True, help_text='Anchor date for first pay period', null=True),
+        ),
+    ]

core/models.py

@@ -53,11 +53,27 @@ class Worker(models.Model):
         return self.name
 
 class Team(models.Model):
+    # === PAY FREQUENCY CHOICES ===
+    # Used for the team's recurring pay schedule (weekly, fortnightly, or monthly)
+    PAY_FREQUENCY_CHOICES = [
+        ('weekly', 'Weekly'),
+        ('fortnightly', 'Fortnightly'),
+        ('monthly', 'Monthly'),
+    ]
+
     name = models.CharField(max_length=200)
     workers = models.ManyToManyField(Worker, related_name='teams')
     supervisor = models.ForeignKey(User, on_delete=models.SET_NULL, null=True, related_name='supervised_teams')
     active = models.BooleanField(default=True)
 
+    # === PAY SCHEDULE ===
+    # These two fields define when the team gets paid.
+    # pay_start_date is the anchor — the first day of the very first pay period.
+    # pay_frequency determines the length of each recurring period.
+    # Both are optional — teams without a schedule work as before.
+    pay_frequency = models.CharField(max_length=15, choices=PAY_FREQUENCY_CHOICES, blank=True, default='')
+    pay_start_date = models.DateField(blank=True, null=True, help_text='Anchor date for first pay period')
+
     def __str__(self):
         return self.name
 

core/templates/core/payroll_dashboard.html

@@ -273,7 +273,8 @@
                                     <form method="POST" action="{% url 'process_payment' wd.worker.id %}"
                                           class="d-inline pay-form">
                                         {% csrf_token %}
-                                        <button type="submit" class="btn btn-sm btn-accent">
+                                        <button type="submit" class="btn btn-sm btn-accent"
+                                                title="Pay all pending items. Use Preview (eye icon) for selective payment.">
                                             <i class="fas fa-money-bill-wave me-1"></i> Pay
                                         </button>
                                     </form>
@@ -1355,6 +1356,8 @@ document.addEventListener('DOMContentLoaded', function() {
     // PREVIEW PAYSLIP — Fetch JSON and build DOM (no innerHTML for data)
     // Refactored into refreshPreview() so we can re-fetch after adding
     // a repayment from the inline form inside the modal.
+    // Now also supports SPLIT PAYSLIP — checkboxes on logs and adjustments,
+    // a "Split at Pay Date" button, and a "Pay Selected" submit button.
     // =================================================================
 
     // Helper: fetch preview data and build the modal content
@@ -1385,6 +1388,49 @@ document.addEventListener('DOMContentLoaded', function() {
 
                 // === Build payslip preview using DOM methods ===
 
+                // -------------------------------------------------------
+                // We'll store references to elements that recalcNetPay()
+                // needs to update when checkboxes change.
+                // -------------------------------------------------------
+                var earningsLabel, earningsVal, adjTotalVal, netVal, negWarnDiv;
+
+                // === RECALCULATE NET PAY ===
+                // Called whenever a log or adjustment checkbox changes.
+                // Counts checked items and recalculates the displayed totals.
+                function recalcNetPay() {
+                    var checkedLogs = modalBody.querySelectorAll('.log-checkbox:checked');
+                    var logTotal = checkedLogs.length * data.day_rate;
+
+                    var adjSum = 0;
+                    modalBody.querySelectorAll('.adj-checkbox:checked').forEach(function(cb) {
+                        var amt = parseFloat(cb.dataset.adjAmount);
+                        adjSum += (cb.dataset.adjSign === '+') ? amt : -amt;
+                    });
+
+                    var net = logTotal + adjSum;
+
+                    // Update the earnings line
+                    if (earningsLabel) earningsLabel.textContent = checkedLogs.length + ' day(s) \u00d7 ' + fmt(data.day_rate);
+                    if (earningsVal) earningsVal.textContent = fmt(logTotal);
+
+                    // Update adjustment total
+                    if (adjTotalVal) {
+                        adjTotalVal.textContent = (adjSum >= 0 ? '+' : '') + fmt(adjSum);
+                        adjTotalVal.className = adjSum >= 0 ? 'text-success' : 'text-danger';
+                    }
+
+                    // Update net pay
+                    if (netVal) {
+                        netVal.textContent = fmt(net);
+                        netVal.className = 'fw-bold ' + (net >= 0 ? 'text-success' : 'text-danger');
+                    }
+
+                    // Show or hide the negative pay warning
+                    if (negWarnDiv) {
+                        negWarnDiv.style.display = net < 0 ? '' : 'none';
+                    }
+                }
+
                 // Worker header
                 var header = document.createElement('div');
                 header.className = 'border-bottom pb-3 mb-3';
@@ -1400,7 +1446,116 @@ document.addEventListener('DOMContentLoaded', function() {
                 }
                 modalBody.appendChild(header);
 
-                // Earnings section
+                // =============================================================
+                // WORK LOGS WITH CHECKBOXES — select which days to pay
+                // =============================================================
+                if (data.logs && data.logs.length > 0) {
+
+                    // --- "Split at Pay Date" button (only if team has a schedule) ---
+                    if (data.pay_period && data.pay_period.has_schedule) {
+                        var periodInfo = document.createElement('div');
+                        periodInfo.className = 'alert alert-info py-2 px-3 small mb-2';
+                        periodInfo.style.backgroundColor = '#e0f2fe';
+                        periodInfo.style.borderColor = '#7dd3fc';
+                        periodInfo.style.color = '#0c4a6e';
+
+                        var infoIcon = document.createElement('i');
+                        infoIcon.className = 'fas fa-calendar-alt me-2';
+                        periodInfo.appendChild(infoIcon);
+                        periodInfo.appendChild(document.createTextNode(
+                            data.pay_period.team_name + ' \u2014 ' +
+                            data.pay_period.frequency + ' pay period: ' +
+                            data.pay_period.start + ' to ' + data.pay_period.end
+                        ));
+                        modalBody.appendChild(periodInfo);
+
+                        var splitBtn = document.createElement('button');
+                        splitBtn.type = 'button';
+                        splitBtn.className = 'btn btn-sm btn-outline-warning mb-3';
+                        var splitIcon = document.createElement('i');
+                        splitIcon.className = 'fas fa-cut me-1';
+                        splitBtn.appendChild(splitIcon);
+                        splitBtn.appendChild(document.createTextNode(
+                            'Split at Pay Date (' + data.pay_period.end + ')'
+                        ));
+                        splitBtn.addEventListener('click', function() {
+                            var periodEnd = data.pay_period.end;
+                            // Uncheck logs after the pay period end date
+                            modalBody.querySelectorAll('.log-checkbox').forEach(function(cb) {
+                                cb.checked = (cb.dataset.logDate <= periodEnd);
+                            });
+                            // Uncheck adjustments after the pay period end date
+                            modalBody.querySelectorAll('.adj-checkbox').forEach(function(cb) {
+                                cb.checked = (cb.dataset.adjDate <= periodEnd);
+                            });
+                            recalcNetPay();
+                        });
+                        modalBody.appendChild(splitBtn);
+                    }
+
+                    var logsH6 = document.createElement('h6');
+                    logsH6.className = 'fw-bold mb-2';
+                    logsH6.textContent = 'Work Logs';
+                    modalBody.appendChild(logsH6);
+
+                    var table = document.createElement('table');
+                    table.className = 'table table-sm mb-2';
+                    var thead = document.createElement('thead');
+                    var headRow = document.createElement('tr');
+
+                    // "Select All" checkbox in header
+                    var thCb = document.createElement('th');
+                    thCb.style.width = '35px';
+                    var selectAllLog = document.createElement('input');
+                    selectAllLog.type = 'checkbox';
+                    selectAllLog.className = 'form-check-input';
+                    selectAllLog.checked = true;
+                    selectAllLog.title = 'Select All / None';
+                    selectAllLog.addEventListener('change', function() {
+                        var checked = selectAllLog.checked;
+                        modalBody.querySelectorAll('.log-checkbox').forEach(function(cb) {
+                            cb.checked = checked;
+                        });
+                        recalcNetPay();
+                    });
+                    thCb.appendChild(selectAllLog);
+                    headRow.appendChild(thCb);
+
+                    ['Date', 'Project'].forEach(function(h) {
+                        var th = document.createElement('th');
+                        th.textContent = h;
+                        headRow.appendChild(th);
+                    });
+                    thead.appendChild(headRow);
+                    table.appendChild(thead);
+
+                    var tbody = document.createElement('tbody');
+                    data.logs.forEach(function(log) {
+                        var tr = document.createElement('tr');
+
+                        // Checkbox cell
+                        var cbTd = document.createElement('td');
+                        var cb = document.createElement('input');
+                        cb.type = 'checkbox';
+                        cb.className = 'form-check-input log-checkbox';
+                        cb.checked = true;
+                        cb.dataset.logId = log.id;
+                        cb.dataset.logDate = log.date;
+                        cb.addEventListener('change', recalcNetPay);
+                        cbTd.appendChild(cb);
+                        tr.appendChild(cbTd);
+
+                        tr.appendChild(createTd(log.date));
+                        tr.appendChild(createTd(log.project));
+                        tbody.appendChild(tr);
+                    });
+                    table.appendChild(tbody);
+                    modalBody.appendChild(table);
+                }
+
+                // =============================================================
+                // EARNINGS SUMMARY — updates dynamically when checkboxes change
+                // =============================================================
                 var earningsH6 = document.createElement('h6');
                 earningsH6.className = 'fw-bold mb-2';
                 earningsH6.textContent = 'Earnings';
@@ -1408,27 +1563,69 @@ document.addEventListener('DOMContentLoaded', function() {
 
                 var earningsRow = document.createElement('div');
                 earningsRow.className = 'd-flex justify-content-between mb-1';
-                var earningsLabel = document.createElement('span');
+                earningsLabel = document.createElement('span');
                 earningsLabel.textContent = data.days_worked + ' day(s) \u00d7 ' + fmt(data.day_rate);
                 earningsRow.appendChild(earningsLabel);
-                var earningsVal = document.createElement('strong');
+                earningsVal = document.createElement('strong');
                 earningsVal.textContent = fmt(data.log_amount);
                 earningsRow.appendChild(earningsVal);
                 modalBody.appendChild(earningsRow);
 
-                // Adjustments section
+                // =============================================================
+                // ADJUSTMENTS WITH CHECKBOXES — select which to include
+                // =============================================================
                 if (data.adjustments && data.adjustments.length > 0) {
                     var adjHr = document.createElement('hr');
                     modalBody.appendChild(adjHr);
 
                     var adjH6 = document.createElement('h6');
-                    adjH6.className = 'fw-bold mb-2';
+                    adjH6.className = 'fw-bold mb-2 d-flex justify-content-between align-items-center';
-                    adjH6.textContent = 'Adjustments';
+
+                    var adjTitle = document.createElement('span');
+                    adjTitle.textContent = 'Adjustments';
+                    adjH6.appendChild(adjTitle);
+
+                    // "Select All" checkbox for adjustments
+                    var adjSelectAllWrap = document.createElement('span');
+                    adjSelectAllWrap.className = 'small fw-normal text-muted';
+                    var selectAllAdj = document.createElement('input');
+                    selectAllAdj.type = 'checkbox';
+                    selectAllAdj.className = 'form-check-input me-1';
+                    selectAllAdj.checked = true;
+                    selectAllAdj.title = 'Select All / None';
+                    selectAllAdj.addEventListener('change', function() {
+                        var checked = selectAllAdj.checked;
+                        modalBody.querySelectorAll('.adj-checkbox').forEach(function(cb) {
+                            cb.checked = checked;
+                        });
+                        recalcNetPay();
+                    });
+                    adjSelectAllWrap.appendChild(selectAllAdj);
+                    adjSelectAllWrap.appendChild(document.createTextNode('All'));
+                    adjH6.appendChild(adjSelectAllWrap);
+
                     modalBody.appendChild(adjH6);
 
                     data.adjustments.forEach(function(adj) {
                         var row = document.createElement('div');
-                        row.className = 'd-flex justify-content-between mb-1';
+                        row.className = 'd-flex align-items-center mb-1';
+
+                        // Checkbox
+                        var cb = document.createElement('input');
+                        cb.type = 'checkbox';
+                        cb.className = 'form-check-input adj-checkbox me-2';
+                        cb.checked = true;
+                        cb.dataset.adjId = adj.id;
+                        cb.dataset.adjDate = adj.date;
+                        cb.dataset.adjAmount = adj.amount;
+                        cb.dataset.adjSign = adj.sign;
+                        cb.addEventListener('change', recalcNetPay);
+                        row.appendChild(cb);
+
+                        // Label + value wrapper (fills remaining space)
+                        var labelWrap = document.createElement('div');
+                        labelWrap.className = 'd-flex justify-content-between flex-grow-1';
+
                         var label = document.createElement('span');
                         label.textContent = adj.type + (adj.project ? ' (' + adj.project + ')' : '');
                         if (adj.description) {
@@ -1437,16 +1634,34 @@ document.addEventListener('DOMContentLoaded', function() {
                             descSmall.textContent = '\u2014 ' + adj.description;
                             label.appendChild(descSmall);
                         }
-                        row.appendChild(label);
+                        labelWrap.appendChild(label);
+
                         var val = document.createElement('span');
                         val.className = adj.sign === '+' ? 'text-success' : 'text-danger';
                         val.textContent = adj.sign + fmt(adj.amount);
-                        row.appendChild(val);
+                        labelWrap.appendChild(val);
+
+                        row.appendChild(labelWrap);
                         modalBody.appendChild(row);
                     });
+
+                    // Adjustment total line
+                    var adjTotalRow = document.createElement('div');
+                    adjTotalRow.className = 'd-flex justify-content-between mt-1 pt-1 border-top';
+                    var adjTotalLabel = document.createElement('small');
+                    adjTotalLabel.className = 'text-muted';
+                    adjTotalLabel.textContent = 'Net adjustments';
+                    adjTotalRow.appendChild(adjTotalLabel);
+                    adjTotalVal = document.createElement('small');
+                    adjTotalVal.className = data.adj_total >= 0 ? 'text-success' : 'text-danger';
+                    adjTotalVal.textContent = (data.adj_total >= 0 ? '+' : '') + fmt(data.adj_total);
+                    adjTotalRow.appendChild(adjTotalVal);
+                    modalBody.appendChild(adjTotalRow);
                 }
 
-                // Net pay
+                // =============================================================
+                // NET PAY — updates dynamically
+                // =============================================================
                 var netHr = document.createElement('hr');
                 netHr.className = 'my-3';
                 modalBody.appendChild(netHr);
@@ -1457,27 +1672,96 @@ document.addEventListener('DOMContentLoaded', function() {
                 netLabel.className = 'fw-bold';
                 netLabel.textContent = 'Net Pay';
                 netRow.appendChild(netLabel);
-                var netVal = document.createElement('h5');
+                netVal = document.createElement('h5');
                 netVal.className = 'fw-bold ' + (data.net_pay >= 0 ? 'text-success' : 'text-danger');
                 netVal.textContent = fmt(data.net_pay);
                 netRow.appendChild(netVal);
                 modalBody.appendChild(netRow);
 
                 // === NEGATIVE NET PAY WARNING ===
-                // If net pay is negative (e.g., advance repayment exceeds earnings),
+                negWarnDiv = document.createElement('div');
-                // show a warning so the admin can edit the repayment before paying.
+                negWarnDiv.className = 'alert alert-warning py-2 px-3 small mt-2 mb-0';
-                if (data.net_pay < 0) {
+                negWarnDiv.style.display = data.net_pay < 0 ? '' : 'none';
-                    var warnDiv = document.createElement('div');
+                var warnIcon = document.createElement('i');
-                    warnDiv.className = 'alert alert-warning py-2 px-3 small mt-2 mb-0';
+                warnIcon.className = 'fas fa-exclamation-triangle me-2';
-                    var warnIcon = document.createElement('i');
+                negWarnDiv.appendChild(warnIcon);
-                    warnIcon.className = 'fas fa-exclamation-triangle me-2';
+                negWarnDiv.appendChild(document.createTextNode(
-                    warnDiv.appendChild(warnIcon);
+                    'Net pay is negative. Consider editing the Advance Repayment ' +
-                    warnDiv.appendChild(document.createTextNode(
+                    'amount on the Pending Payments table before processing.'
-                        'Net pay is negative. Consider editing the Advance Repayment ' +
+                ));
-                        'amount on the Pending Payments table before processing.'
+                modalBody.appendChild(negWarnDiv);
-                    ));
+
-                    modalBody.appendChild(warnDiv);
+                // =============================================================
-                }
+                // PAY SELECTED BUTTON — submits only checked logs/adjustments
+                // =============================================================
+                var payBtn = document.createElement('button');
+                payBtn.type = 'button';
+                payBtn.className = 'btn btn-accent w-100 mt-3';
+                var payIcon = document.createElement('i');
+                payIcon.className = 'fas fa-money-bill-wave me-2';
+                payBtn.appendChild(payIcon);
+                payBtn.appendChild(document.createTextNode('Pay Selected'));
+
+                payBtn.addEventListener('click', function() {
+                    // Gather checked log IDs
+                    var logIds = [];
+                    modalBody.querySelectorAll('.log-checkbox:checked').forEach(function(cb) {
+                        logIds.push(cb.dataset.logId);
+                    });
+                    // Gather checked adjustment IDs
+                    var adjIds = [];
+                    modalBody.querySelectorAll('.adj-checkbox:checked').forEach(function(cb) {
+                        adjIds.push(cb.dataset.adjId);
+                    });
+
+                    if (logIds.length === 0 && adjIds.length === 0) {
+                        alert('Nothing selected to pay.');
+                        return;
+                    }
+
+                    // Build a hidden form and submit it
+                    var form = document.createElement('form');
+                    form.method = 'POST';
+                    form.action = '/payroll/pay/' + data.worker_id + '/';
+
+                    // CSRF token
+                    var csrf = document.createElement('input');
+                    csrf.type = 'hidden';
+                    csrf.name = 'csrfmiddlewaretoken';
+                    csrf.value = '{{ csrf_token }}';
+                    form.appendChild(csrf);
+
+                    // Selected log IDs
+                    logIds.forEach(function(lid) {
+                        var inp = document.createElement('input');
+                        inp.type = 'hidden';
+                        inp.name = 'selected_log_ids';
+                        inp.value = lid;
+                        form.appendChild(inp);
+                    });
+
+                    // Selected adjustment IDs
+                    adjIds.forEach(function(aid) {
+                        var inp = document.createElement('input');
+                        inp.type = 'hidden';
+                        inp.name = 'selected_adj_ids';
+                        inp.value = aid;
+                        form.appendChild(inp);
+                    });
+
+                    document.body.appendChild(form);
+
+                    // Prevent double-click
+                    payBtn.disabled = true;
+                    payBtn.textContent = '';
+                    var procSpinner = document.createElement('span');
+                    procSpinner.className = 'spinner-border spinner-border-sm me-2';
+                    payBtn.appendChild(procSpinner);
+                    payBtn.appendChild(document.createTextNode('Processing...'));
+
+                    form.submit();
+                });
+                modalBody.appendChild(payBtn);
 
                 // =============================================================
                 // OUTSTANDING LOANS & ADVANCES — shows active balances with
@@ -1628,39 +1912,6 @@ document.addEventListener('DOMContentLoaded', function() {
                         modalBody.appendChild(card);
                     });
                 }
-
-                // Work log details
-                if (data.logs && data.logs.length > 0) {
-                    var wlHr = document.createElement('hr');
-                    modalBody.appendChild(wlHr);
-
-                    var logsH6b = document.createElement('h6');
-                    logsH6b.className = 'fw-bold mb-2';
-                    logsH6b.textContent = 'Work Log Details';
-                    modalBody.appendChild(logsH6b);
-
-                    var table = document.createElement('table');
-                    table.className = 'table table-sm mb-0';
-                    var thead = document.createElement('thead');
-                    var headRow = document.createElement('tr');
-                    ['Date', 'Project'].forEach(function(h) {
-                        var th = document.createElement('th');
-                        th.textContent = h;
-                        headRow.appendChild(th);
-                    });
-                    thead.appendChild(headRow);
-                    table.appendChild(thead);
-
-                    var tbody = document.createElement('tbody');
-                    data.logs.forEach(function(log) {
-                        var tr = document.createElement('tr');
-                        tr.appendChild(createTd(log.date));
-                        tr.appendChild(createTd(log.project));
-                        tbody.appendChild(tr);
-                    });
-                    table.appendChild(tbody);
-                    modalBody.appendChild(table);
-                }
             })
             .catch(function() {
                 // Show error (safe hardcoded content)

core/views.py

@@ -60,6 +60,77 @@ def is_staff_or_supervisor(user):
     return is_admin(user) or is_supervisor(user)
 
 
+# === PAY SCHEDULE HELPERS ===
+# These help figure out a worker's pay period based on their team's schedule.
+
+def get_worker_active_team(worker):
+    """Return the worker's active team (first one found), or None."""
+    return worker.teams.filter(active=True).first()
+
+
+def get_pay_period(team, reference_date=None):
+    """
+    Calculate the current pay period's start and end dates for a team.
+
+    Returns (period_start, period_end) or (None, None) if the team has
+    no pay schedule configured.
+
+    How it works:
+    - pay_start_date is the "anchor" — the first day of the very first pay period.
+    - pay_frequency determines the length of each period (7, 14, or ~30 days).
+    - We step forward from the anchor in period-length increments until
+      we find the period that contains reference_date (today by default).
+    """
+    if not team or not team.pay_frequency or not team.pay_start_date:
+        return (None, None)
+
+    if reference_date is None:
+        reference_date = timezone.now().date()
+
+    anchor = team.pay_start_date
+
+    # === WEEKLY / FORTNIGHTLY ===
+    # Simple fixed-length periods (7 or 14 days).
+    if team.pay_frequency in ('weekly', 'fortnightly'):
+        period_days = 7 if team.pay_frequency == 'weekly' else 14
+
+        # How many full periods have passed since the anchor?
+        days_since_anchor = (reference_date - anchor).days
+        if days_since_anchor < 0:
+            # reference_date is before the anchor — use the first period
+            return (anchor, anchor + datetime.timedelta(days=period_days - 1))
+
+        periods_passed = days_since_anchor // period_days
+        period_start = anchor + datetime.timedelta(days=periods_passed * period_days)
+        period_end = period_start + datetime.timedelta(days=period_days - 1)
+        return (period_start, period_end)
+
+    # === MONTHLY ===
+    # Step through calendar months from the anchor's day-of-month.
+    # E.g., anchor = Jan 15 means periods are: Jan 15–Feb 14, Feb 15–Mar 14, etc.
+    elif team.pay_frequency == 'monthly':
+        anchor_day = anchor.day
+        current_start = anchor
+
+        # Walk forward month by month until we find the period containing today
+        for _ in range(120):  # Safety limit — 10 years of months
+            if current_start.month == 12:
+                next_month, next_year = 1, current_start.year + 1
+            else:
+                next_month, next_year = current_start.month + 1, current_start.year
+
+            # Clamp anchor day to the max days in that month (e.g., 31 → 28 for Feb)
+            max_day = cal_module.monthrange(next_year, next_month)[1]
+            next_start = datetime.date(next_year, next_month, min(anchor_day, max_day))
+            current_end = next_start - datetime.timedelta(days=1)
+
+            if reference_date <= current_end:
+                return (current_start, current_end)
+            current_start = next_start
+
+    return (None, None)
+
+
 # === HOME DASHBOARD ===
 # The main page users see after logging in. Shows different content
 # depending on whether the user is an admin or supervisor.
@@ -1121,16 +1192,36 @@ def process_payment(request, worker_id):
         # will wait here until this transaction commits.
         worker = Worker.objects.select_for_update().get(id=worker_id)
 
+        # === SPLIT PAYSLIP SUPPORT ===
+        # If the POST includes specific log/adjustment IDs (from the preview
+        # modal's checkboxes), only pay those selected items.
+        # If no IDs provided (e.g., the quick "Pay" button on the table),
+        # fall back to paying everything — backward compatible.
+        selected_log_ids = [int(x) for x in request.POST.getlist('selected_log_ids') if x.isdigit()]
+        selected_adj_ids = [int(x) for x in request.POST.getlist('selected_adj_ids') if x.isdigit()]
+
         # Find unpaid logs for this worker (inside the lock, so this
         # result is guaranteed to be up-to-date)
-        unpaid_logs = worker.work_logs.exclude(
+        all_unpaid_logs = worker.work_logs.exclude(
             payroll_records__worker=worker
         )
+
+        # If specific logs were selected, only pay those
+        if selected_log_ids:
+            unpaid_logs = all_unpaid_logs.filter(id__in=selected_log_ids)
+        else:
+            unpaid_logs = all_unpaid_logs
+
         log_count = unpaid_logs.count()
         logs_amount = log_count * worker.daily_rate
 
-        # Find pending adjustments
+        # Find pending adjustments — filter to selected if IDs provided
-        pending_adjs = list(worker.adjustments.filter(payroll_record__isnull=True))
+        all_pending_adjs = list(worker.adjustments.filter(payroll_record__isnull=True))
+        if selected_adj_ids:
+            selected_adj_set = set(selected_adj_ids)
+            pending_adjs = [a for a in all_pending_adjs if a.id in selected_adj_set]
+        else:
+            pending_adjs = all_pending_adjs
 
         if log_count == 0 and not pending_adjs:
             # Nothing to pay — either everything is already paid (duplicate
@@ -1660,20 +1751,25 @@ def preview_payslip(request, worker_id):
 
     worker = get_object_or_404(Worker, id=worker_id)
 
-    # Find unpaid logs
+    # Find unpaid logs — include the log ID so the frontend can send
+    # selected IDs back for split payslip (selective payment).
     unpaid_logs = []
     for log in worker.work_logs.select_related('project').prefetch_related('payroll_records').all():
         paid_worker_ids = {pr.worker_id for pr in log.payroll_records.all()}
         if worker.id not in paid_worker_ids:
             unpaid_logs.append({
+                'id': log.id,
                 'date': log.date.strftime('%Y-%m-%d'),
                 'project': log.project.name,
             })
 
+    # Sort logs by date so the split makes visual sense (oldest first)
+    unpaid_logs.sort(key=lambda x: x['date'])
+
     log_count = len(unpaid_logs)
     log_amount = float(log_count * worker.daily_rate)
 
-    # Find pending adjustments
+    # Find pending adjustments — include ID and date for split payslip
     pending_adjs = worker.adjustments.filter(
         payroll_record__isnull=True
     ).select_related('project')
@@ -1684,11 +1780,13 @@ def preview_payslip(request, worker_id):
         sign = '+' if adj.type in ADDITIVE_TYPES else '-'
         adj_total += float(adj.amount) if adj.type in ADDITIVE_TYPES else -float(adj.amount)
         adjustments_list.append({
+            'id': adj.id,
             'type': adj.type,
             'amount': float(adj.amount),
             'sign': sign,
             'description': adj.description,
             'project': adj.project.name if adj.project else '',
+            'date': adj.date.strftime('%Y-%m-%d'),
         })
 
     # === ACTIVE LOANS & ADVANCES ===
@@ -1707,7 +1805,21 @@ def preview_payslip(request, worker_id):
             'reason': loan.reason or '',
         })
 
+    # === PAY PERIOD INFO ===
+    # If the worker belongs to a team with a pay schedule, include the
+    # current period boundaries so the "Split at Pay Date" button can work.
+    team = get_worker_active_team(worker)
+    period_start, period_end = get_pay_period(team)
+    pay_period = {
+        'has_schedule': period_start is not None,
+        'start': period_start.strftime('%Y-%m-%d') if period_start else None,
+        'end': period_end.strftime('%Y-%m-%d') if period_end else None,
+        'frequency': team.pay_frequency if team else None,
+        'team_name': team.name if team else None,
+    }
+
     return JsonResponse({
+        'worker_id': worker.id,
         'worker_name': worker.name,
         'worker_id_number': worker.id_number,
         'day_rate': float(worker.daily_rate),
@@ -1718,6 +1830,7 @@ def preview_payslip(request, worker_id):
         'net_pay': log_amount + adj_total,
         'logs': unpaid_logs,
         'active_loans': loans_list,
+        'pay_period': pay_period,
     })