Timesheet Validator - Validation Rules

Business Logic:
On scheduled work days (weekday or 5.5-day Saturday), employees are expected to work. If no time is entered and no remarks explain the absence, this indicates unapproved leave. PT employees are exempt from this rule.

Example:
Date: Jan 15 (Mon) | C/D/H: All empty → Error
Date: Jan 18 (Sat, 5.5-day staff) | C/D/H: All empty → Error

Business Logic:
Differs from Rule 1 (fully empty row) — this row has some text in Col G or Col H, but none of it matches a recognised leave code. The employee wrote something but it cannot be interpreted as approved leave.

Detection uses whole-word matching (HasLeaveCode) on upCombined = UCase$(ColG & " " & ColH). Both columns are scanned together. If any exempt code is found, this rule does not fire:
• AL / SL / NPL — standard Col G dropdown leave types
• NPSL — Col H only (Others path); exempts and counted as NPL
• PUBLIC HOLIDAY — substring match (not whole-word)

Both C and D must be empty — if only one is filled, routes to Rule 2.7 instead. PT employees are exempt from this rule entirely.

Examples:
Jan 20 (Mon) | C/D: Empty, Col G: "Doctor appointment" → Error (no recognised code)
Jan 20 (Mon) | C/D: Empty, Col G: "AL (AM)" → No error ✅ (AL found → routes to Rule 2.5 (FT))
Jan 25 (Mon) | C/D: Empty, Col G: "Others", Col H: "NPSL" → No Rule 2 error ✅ (NPSL exempts, counted as NPL); Rule 16 fires

Business Logic:
If marking half-day leave (AM or PM), the employee should still work the other half and enter those hours in columns C/D. PT employees are exempt from this rule — they face Rule 2.5 (PT) instead. The (AM)/(PM) marker is read from Col G for standard leave types, and from Col H when Col G = "OTHERS".

Example:
Date: Feb 5 (Wed) | C/D: Empty, Col G: "AL (AM)" → Error
Date: Jan 18 (Sat, 5.5-day staff) | C/D: Empty, Col G: "SL (PM)" → Error

Business Logic:
PT equivalent of Rule 2.5 (FT). PT employees are exempt from Rule 2.5 (FT) (FT half-day check), but if they explicitly mark a half-day marker on a weekday with no time entries, the same data-entry error applies.

Example:
PT employee | Date: Feb 5 (Wed) | C/D: Empty, Col G: "AL (AM)" → Error

Business Logic:
Both start time (C) and end time (D) must be provided together. Having one without the other is a data entry error regardless of what leave codes are present in G/H.

Examples:
Date: Jan 20 (Mon) | C: 09:00, D: Empty, Remarks: "AL" → Error
Date: Jan 20 (Mon) | C: Empty, D: 18:00, Remarks: "" → Error

Business Logic:
PT employees are exempt from Rules 1, 2, and 2.5 (FT) (leave without reason). However, having only one of start/end time is still a data-entry error on any day type.

Example:
PT employee | Date: Jan 20 (Mon) | C: 09:00, D: Empty → Error

Business Logic:
Full-day NPL or NPSL means no work should be recorded. If C/D are filled alongside a full-day NPL/NPSL entry (without an AM/PM marker), the entry is contradictory.

Half-day NPL(AM) or NPL(PM) is valid — the employee works the other half and enters times in C/D.

Leave source rules for this check:
• Non-Others path: NPL/NPSL detected from Col G prefix (e.g. "NPL (Full Day)", "NPSL")
• Others path (Col G = "OTHERS"): only NPSL in Col H triggers this check (exact-case match). "NPL" in Col H under Others is a data-entry mistake and is not treated as full-day NPL — employees must use the Col G NPL dropdown instead.

Example (error, non-Others):
Date: Mar 4 (Tue) | C: 09:00, D: 18:00, Col G: "NPL (Full Day)" → Error

Example (error, Others path):
Date: Mar 4 (Tue) | C: 09:00, D: 18:00, Col G: "OTHERS", Col H: "NPSL" → Error

Example (valid):
Date: Mar 4 (Tue) | C: 13:00, D: 18:00, Col G: "NPL (AM)" → Half-day NPL, afternoon worked → OK

Business Logic:
If time is entered (C & D), the working hours formula (E) should calculate a numeric value. "N/A" or errors indicate formula/data issues.

Example:
Date: Jan 12 (Mon) | C: 09:00, D: 18:00, E: "N/A", actual: 9.0h → Error

Business Logic:
The working hours in column E must match the calculated difference between end time and start time [(D-C) × 24].

Example:
Date: Jan 18 (Mon) | C: 09:00, D: 18:00, E: 8.5h, actual: 9.0h → Error

Business Logic:
Employees should work their expected hours unless on approved leave. Small discrepancies within tolerance (0.5h) are allowed for rounding.

Example:
Date: Feb 8 (Mon) | actual: 7.5h, expected: 9.0h → 7.5+0.5=8.0<9.0 → Error

Business Logic:
Overtime is only permitted when actual hours exceed expected hours + tolerance. Working exactly expected hours = no OT allowed.

Example:
Date: Jan 22 (Mon) | actual: 9.0h, expected: 9.0h, OT: 1.0h → Error

Business Logic - OT buffer rule (hrOTFreeHr):
When HR column "OT free hour" = Y, employees must work >1 hour beyond expected hours before OT is counted.
• hrOTFreeHr = Y: actual - expected ≤ 1h → No OT; > 1h → OT = excess − 1
• hrOTFreeHr = N: OT = actual - expected (no buffer)

Example:
Date: Feb 3 (Wed) | actual: 11.0h, expected: 9.0h, OT(F): 2.0h, calcOT: 11-9-1=1.0h → Error

Business Logic:
5.5-day employees are expected to work Saturdays (typically 4 hours). Partial hours without a valid leave explanation require justification. Leave detection scans upCombined (Col G + Col H) — same mechanism as Rule 2.

Example:
Date: Jan 11 (Sat) | Type: 5.5-day, expected: 4.0h, actual: 2.5h, Col G: "Personal matters" → Error
Date: Jan 11 (Sat) | Type: 5.5-day, expected: 4.0h, actual: 2.5h, Col G: "AL (AM)" → OK ✅ (AL found)

Business Logic:
5.5-day staff Saturdays are working half-days. Any leave taken on a Saturday should specify AM or PM to clarify which half was taken. A warning is generated when a leave type is present but no half-day marker is found.

Example (warning):
Date: Jan 11 (Sat) | 5.5-day, Col G: "SL" → Warning: "Jan 11 - Saturday SL should specify (AM) or (PM)"

Example (valid):
Date: Jan 11 (Sat) | 5.5-day, Col G: "SL (AM)" → OK ✅

Active leave types: AL, SL, NPL only. NPSL is routed through NPL (message shows "NPL" not "NPSL").

Business Logic - Saturday OT Rule:
• First 4 hours = regular working hours
• Hours beyond 4 = overtime
• Formula: Saturday OT = actualHours - 4
• No 1-hour buffer (unlike weekday Rule 7)

Example:
Date: Jan 18 (Sat) | Type: 5.5-day, actual: 6.0h, OT(F): 2.5h, calcOT: 6.0-4.0=2.0h → Error

Business Logic - Rest day work rule:
• All hours worked on a rest day = OT (no "regular hours")
• C-D, E, and F must all match
• Applies to: Sunday, Public Holiday, AND Saturday for 5-day staff
• 5-day staff Saturday is treated as a rest day (same as Sun/PH)
• 5.5-day staff Saturday is handled separately by Rules 11 & 12

Example (Sun/PH):
Date: Jan 1 (Sun-PH) | C: 10:00, D: 15:00, E: 5.0h, F: 4.5h → Error

Example (5-day Saturday):
Date: Jan 11 (Sat) | 5-day staff | C: 10:00, D: 14:00, E: 4.0h, F: 3.5h → Error

Business Logic:
Sundays, public holidays, and Saturdays for 5-day staff are all rest days. No work = no error.
5-day staff Saturday is a rest day (same treatment as Sun/PH).

Example (Sun/PH):
Date: Jan 1 (Sun-New Year) | C/D: Empty → OK ✅ (no error)

Example (5-day Saturday):
Date: Jan 11 (Sat) | 5-day staff | C/D: Empty → OK ✅ (no error)

Business Logic:
Leave types shouldn't be marked on rest days (Sunday, Public Holiday, or Saturday for 5-day staff) since these are already non-working days.

AL / NPL on rest day: NOT counted. Warning remark + MarkError G:H.
SL on rest day: IS counted (cntSL += 0.5 or 1). Informational remark only, no MarkError. SL is counted on rest days because consecutive SL tracking spans across weekends/PH.

Example (AL):
Date: Jan 1 (Sun-New Year) | Col G: "AL" → Warning: "Jan 1 - AL marked on rest day (Sun/PH)" + MarkError

Example (SL):
Date: Jan 1 (Sun-New Year) | Col G: "SL" → Info: "Jan 1 - SL on rest day (included in consecutive SL streak)" (no MarkError, SL counted)

Why does 5-day Saturday say "(Sun/PH)" in the message?
The message template was written when this rule only covered Sunday and Public Holidays. 5-day staff Saturday was added later but the label was not updated.

Business Logic:
When Col G = "OTHERS", leave resolution switches to Col H. Only NPSL from Col H is counted (as NPL). An informational remark is always generated so HR can review what was entered in Col H.

Leave accumulation under Others:
• AL, SL, NPL (from Col G dropdown) — counted normally
• NPSL (Col H) — counted as NPL (effHasNPL = colHHasNPSL)
Example:
FT employee | Col G: "Others", Col H: "NPSL" → NPSL counted as NPL + informational remark