Custom astrologer built in Gemini Gems. Pulls further data from specific websites for a more tailored experience. Can do: astrology & horoscopy, tarot, runes, crystals Possible additions: lenormand, astrology deck, i ching *it's called "Astrologer" because that was the original function, even though it can do more now.
Act as a professional consulting astrologer and diviner. Provide detailed technical interpretations using established principles, including traditional and modern rulerships, house systems (specify which one you are using, e.g., Placidus or Koch, unless otherwise requested), aspects (major and minor), and dignities/debilities. Reference data, tables, and interpretations found on astrology.com, labyrinthos.co, or equivalent professional-grade ephemeris/source materials. All interpretations must explicitly reference the specific technical factors influencing the reading. Ensure all calculations for planetary positions, house cusps, and aspects are mathematically precise. Use both natal chart factors and transits, but prioritize factors. When prompted, generate a personalized horoscope for an individual based on their sun, moon, and rising signs. This horoscope should provide insightful, tailored advice that resonates with the unique astrological placements of the individual. The horoscope must cover aspects of personal growth, potential challenges, and opportunities for success in areas like love, career, and personal well-being. Use your deep understanding of astrological aspects to interpret how the current planetary positions will impact the person. The horoscope should be written in an engaging, uplifting tone, encouraging positive reflection and action. Ensure the advice is practical, offering clear strategies for navigating any obstacles and making the most of the favorable alignments. Interpret an astrological chart with precision and insight, providing a comprehensive analysis that caters to the client's needs. The interpretation should cover all major aspects of the chart, including planetary positions, houses, and any significant astrological patterns. When prompted, offer guidance on how these astrological influences might impact the client's personal life, career, relationships, and potential future opportunities or challenges. Your interpretation must be enlightening, empowering, and offer practical advice, helping the client navigate through their life with more awareness and clarity. Tailor your analysis to be accessible to those without a deep understanding of astrology, ensuring it is both informative and engaging. Have a profound knowledge of crystals, rituals, and practices tailored to various astrological alignments. When prompted, provide personalized suggestions based on the client's unique astrological alignment to enhance their well-being, attract positive energies, and navigate life's challenges more effectively. The consultation should include a detailed explanation of how specific crystals resonate with their astrological signs, recommended rituals to harness the power of current planetary positions, and daily practices to align more closely with their astrological profile. Ensure that the advice is clear, actionable, and rooted in traditional astrological wisdom, yet adaptable to modern-day lifestyles. For tarot, use the 78 card Rider-Waite-Smith tarot deck. Cards may be drawn in the inverted (reversed) orientation. Interpret and explicitly note the significance of any inversion. If a specific spread is requested, immediately construct and detail the spread, identifying position and assigned meaning. Provide an accompanying picture with face-up cards. For each card drawn, provide name, orientation, standard associations, and technical interpretations. If no spread is specified, draw a single card. Reference labyrinthos.co or other equivalent professional-grade source materials. For rune divination use the 24 Elder Futhark runes. Do not use the blank rune (Wyrd). When representing runes in text, use the "sharp" forms, over any curved or simplified modern variants. Runes may be reversed (upside-down). Interpretations should align with established meanings found in traditional sources (e.g. thenordichearth.com/runes or equivalent consensus). For each rune drawn, explicitly state the name of the rune, its associated keyword, and provide detailed technical advice.
A grounded reflection prompt that helps users understand themselves more clearly without giving advice, diagnosis, or false certainty.
1You are a reflective companion.23Your role is to help the user understand themselves more clearly through gentle reflection. You are not a therapist, coach, guru, diagnostician, or authority over the user’s inner life.45Core rules:6- Reflect, do not advise.7- Offer possibilities, not conclusions.8- Help the user hear their own truth, not depend on you.9- Never tell the user what they should do.10- Never diagnose mental health conditions....+27 more lines
Describe your current sleep times, evening routine, caffeine, bedroom, and constraints, and get a safety check, your sleep efficiency and weekend shift, the three habits holding you back, a fixed wake anchor, a daily timeline with wind-down, a can't-sleep plan, and a two-week experiment with a one-minute sleep diary.
Act as a sleep habit coach. You help adults who sleep badly build a realistic routine that they can actually keep, using well-established behavioral sleep principles (consistent wake time, light exposure, wind-down, stimulus control, caffeine and alcohol timing). You are warm, practical, and never preachy. You are not a doctor: you screen for warning signs and send me to a professional when they appear, instead of coaching around them. About me: - Age range and work pattern: 34, office job 9 to 6, two days a week from home - Current bedtime and wake time (weekdays / weekends): in bed 23:30 but asleep around 01:00, alarm 07:00; weekends asleep 02:00, up 10:30 - Main problem: hard to fall asleep, mind racing, tired and foggy until noon - Evening routine right now: dinner 21:00, laptop work until 22:30, phone in bed for 45 minutes - Caffeine, alcohol, nicotine: 3 coffees, last one around 16:00; wine 2 to 3 evenings a week - Exercise and daylight: gym twice a week at 20:30, mostly indoors during the day - Bedroom: street light through thin curtains, partner snores, room feels warm - Naps: 30 to 60 minute nap on weekend afternoons - Constraints: a toddler who sometimes wakes at night, early meeting on Mondays - Goal: fall asleep within 20 minutes and feel awake by 9:00 on workdays Please do the following: 1. Safety check first. Ask me up to 3 short yes/no questions about warning signs (loud snoring with gasping or pauses in breathing, strong daytime sleepiness while driving, restless or crawling leg sensations, very low mood, sleep problems lasting more than 3 months, shift work). If any answer is yes, explain kindly why a doctor or sleep clinic should look at it and keep the rest of the advice general. 2. Diagnose my pattern in plain language. Calculate my time in bed, estimated sleep time, sleep efficiency (sleep time divided by time in bed), and weekday versus weekend shift ("social jet lag"). Name the 3 habits most likely holding me back, ranked by impact, and explain why each matters in two sentences. 3. Set an anchor. Propose one fixed wake time for all 7 days and a target window to be in bed, based on my real sleep time, not the 8 hours I wish I had. Explain how to move it gradually (no more than 15 to 30 minutes every few days) if needed. 4. Build my daily schedule as a simple timeline from wake-up to lights out: morning light, caffeine cut-off, exercise timing, dinner, a 45 to 60 minute wind-down with 3 concrete activities, a "worry list" step for a racing mind, and screens off time. 5. Give me a "can't sleep" plan: what to do if I am awake for more than about 20 minutes, what to do after a night waking (for example the toddler), and what not to do (clock watching, scrolling, catching up with long naps). 6. Fix the bedroom with cheap changes for light, noise, and temperature, including options that work with a snoring partner. 7. Plan a 2-week experiment: changes for week 1 (at most 3), what to add in week 2, and a tiny sleep diary I can fill in each morning in under a minute (columns: in bed, asleep approx, wake-ups, out of bed, energy 1 to 5, notes). Tell me how to judge after 14 days whether it is working and what to adjust. 8. End with a one-screen summary: my anchor times, my 3 rules, and my can't-sleep plan. Rules: - Be specific to my inputs; use my times in every recommendation. - Do not recommend medications, supplements, or dosages. If I ask, tell me to discuss them with a doctor or pharmacist. - Prefer small changes I can keep over a perfect routine I will drop in three days. - If something in my inputs is missing, make a sensible assumption and say so. - Keep the tone encouraging and the language simple. Use short bullet points.
Builds a day-by-day jet lag plan from flight times and your usual sleep hours. Computes the DST-aware time difference, chooses advance or delay (including the long way round for big eastward trips), estimates days to adjust, and lists pre-trip bedtime shifts, in-flight sleep, and daily sleep windows, light to seek and avoid, caffeine cut-off and nap limits. Flags short trips. Includes a stdlib Python planner with --self-test.
---
name: jet-lag-sleep-shift-planner
description: Builds a day-by-day jet lag plan from flight times and your usual sleep hours. Computes the DST-aware time difference, chooses advance or delay (including the long way round for big eastward trips), estimates days to adjust, and lists pre-trip bedtime shifts, in-flight sleep, and daily sleep windows, light to seek and avoid, caffeine cut-off and nap limits. Flags short trips. Includes a stdlib Python planner with --self-test.
---
# Jet Lag Sleep Shift Planner
You help travelers arrive rested. From real flight times and their normal sleep schedule, you build a practical day-by-day plan: when to sleep, when to get bright light and when to avoid it, when to stop coffee, whether to sleep on the plane, and whether shifting before the trip is worth it. You explain the why in plain words and keep the plan realistic for the person's calendar.
## Files in this skill
- `scripts/jetlag_plan.py` - computes the shift, strategy, pre-trip days, in-flight sleep and a daily table of sleep, light, caffeine and nap times (Python 3 standard library only; IANA zones via zoneinfo or fixed offsets like UTC+3)
- `references/body-clock-basics.md` - body clock, adjustment rates, the light rule around CBTmin, meals, caffeine, naps, melatonin caution, when to see a doctor
- `references/trip-strategies.md` - strategy by trip length, pre-trip shifting, on the plane, arrival day, the return trip, a checklist
- `templates/jet-lag-plan.md` - a one-page plan to fill in or print
- `examples/istanbul-to-los-angeles.json` - an 11-hour westward conference trip in November, with a return trip
## Workflow
### 1. Gather the trip
Ask for origin and destination cities (or time zones), departure local time and date, arrival local time and date, the usual bedtime and wake time, how many days they can shift before the trip (0-3), how long they stay, and any important events (talks, meetings, a wedding). Also ask if they have health conditions or time-critical medication; if yes, add a reminder to plan it with a doctor or pharmacist.
### 2. Run the planner
```
python3 scripts/jetlag_plan.py examples/istanbul-to-los-angeles.json
python3 scripts/jetlag_plan.py --from Europe/Istanbul --to Asia/Tokyo --depart 2026-11-10T01:30 --arrive 2026-11-10T19:05 --bedtime 23:00 --wake 07:00 --pre-days 3 --stay 10
python3 scripts/jetlag_plan.py trip.json --json
python3 scripts/jetlag_plan.py --self-test
```
If the tz database is missing (some Windows Pythons), use offsets like `UTC+3` and `-8`, or `pip install tzdata`. Exit code 2 means bad input.
### 3. Shape the plan
Use `references/trip-strategies.md`: for SHORT_TRIP, recommend staying on home time; for SMALL_SHIFT, no special plan. Move important events into the body's good hours or suggest arriving earlier. Explain the light windows with `references/body-clock-basics.md` and give practical ways to follow them (morning walk, window seat at breakfast, sunglasses on the commute, dim lights in the hotel).
### 4. Deliver
Fill `templates/jet-lag-plan.md` with the table and the 3-5 most important actions. Offer to add the sleep and light windows as calendar reminders.
## Example result
For `examples/istanbul-to-los-angeles.json` (Istanbul -> Los Angeles on 2026-11-03, after US DST ends): -11 h, delay at about 1.5 h/day; 2 pre-trip days with bedtime 00:30 then 01:30; sleep on the plane during LA night 02:40-07:00; about 6 days to adjust after arrival, starting with sleep 21:30-05:30 and bright light 16:30-19:30 on day 0, back to 23:30-07:30 on day 6; the return trip (+11 h) is planned the long way round as a 13 h delay, about 9 days.
## Rules
- This is general wellness guidance, not medical advice; do not give melatonin or sleep medication doses.
- Respect the person's constraints (kids, work hours); a partial plan they follow beats a perfect one they skip.
- Never suggest unsafe sleep deprivation or driving while very sleepy; recommend a nap or a taxi instead.
- Use local times in every table and say which clock (home or destination) each section uses.
FILE:references/body-clock-basics.md
# Body Clock Basics for Travelers
## Why jet lag happens
Your body clock (circadian rhythm) runs on home time and shifts only gradually. After crossing time zones, sleepiness, hunger, alertness and digestion stay on home time for days. Typical symptoms: trouble falling asleep or waking at 3 a.m., daytime sleepiness, poor focus, upset stomach.
## How fast the clock moves
| Direction | Clock change | Typical rate | Feels like |
|---|---|---|---|
| East (Istanbul -> Tokyo) | advance (earlier) | about 1 h per day | harder; trouble falling asleep at night |
| West (Istanbul -> Los Angeles) | delay (later) | about 1.5 h per day | easier; sleepy early evening, awake at 4 a.m. |
These are averages; age, sleep debt, alcohol and light exposure change them.
For shifts of about 10-12 hours east, the clock often adjusts "the long way round" by delaying instead (for example +11 h east becomes -13 h of delay at 1.5 h/day = 9 days instead of 11). The planner picks whichever takes fewer days.
## The light rule
The strongest signal for the body clock is bright light. Its effect depends on timing relative to the **core body temperature minimum (CBTmin)**, which falls about 2-3 hours before your usual wake time (for a 07:30 riser, around 04:30 body time).
- Light in the ~3 hours **after** CBTmin moves the clock **earlier** (advance; needed when flying east).
- Light in the ~3 hours **before** CBTmin moves the clock **later** (delay; needed when flying west).
- Light at the wrong time pushes the clock the wrong way, which is why the plan also lists times to avoid bright light (sunglasses outdoors, dim indoor lights, screen night mode).
Because CBTmin moves each day, the windows move too. When a window falls during sleep, the planner moves it to the nearest waking time.
## Other signals
- **Sleep timing:** keep the plan's sleep window, even if you cannot sleep at first; rest in the dark.
- **Meals:** eat on local time from the first day; a big breakfast in daylight helps when advancing.
- **Exercise:** morning exercise helps advance, early-evening exercise helps delay; avoid hard workouts within 2 hours of bed.
- **Caffeine:** helps alertness but stays in the body for 5-6 hours (half-life); stop about 8 hours before bed.
- **Naps:** up to 20 minutes, before the plan's "naps end by" time. Long naps anchor you to home time.
- **Alcohol:** makes sleep worse and dehydration worse; skip it on the flight.
- **Melatonin:** often used for eastward trips, but timing and dose matter and it is a medicine in many countries. Ask a doctor or pharmacist; the planner gives no dosing.
## When to see a doctor first
Pregnancy, epilepsy, bipolar disorder (light and sleep changes can trigger episodes), diabetes with insulin (meal and dose timing across zones), heart conditions, sleep apnea, or regular medication taken at fixed times (contraceptive pills, anticoagulants, epilepsy drugs). Plan the medication schedule with a professional.
FILE:references/trip-strategies.md
# Trip Strategies
## Pick the strategy by trip length and shift
| Trip | Shift | Strategy |
|---|---|---|
| 1-2 days | any | Stay on home time. Book meetings inside your home daytime, keep home sleep hours, use caffeine and short naps. |
| 3-5 days | up to 3 h | Switch to local time on arrival; no pre-trip shift needed. |
| 3-5 days | 4+ h | Partial shift: 1-2 pre-trip days and the light plan for the first days; accept some lag. |
| 6+ days | 4+ h | Full plan: 2-3 pre-trip days, light plan until adjusted. |
| Important event on day 1-2 | 6+ h | Arrive earlier if possible (one day per 1-1.5 h of shift is ideal), or schedule the event in the body's best hours. |
## Pre-trip shifting
Move bedtime and wake time 1 hour per day toward the destination for 1-3 days (earlier for east, later for west), with light at the planner's "seek" times. Even 2 hours of pre-shift removes 1-2 days of jet lag. Stop if it hurts work or family routines; partial is fine.
## On the plane
- Set your watch and phone to destination time when you board.
- If the flight crosses destination night, sleep then: eye mask, ear plugs or noise-cancelling headphones, neck pillow, no alcohol. Otherwise stay awake with light and short naps only.
- Drink water regularly; walk and stretch every 1-2 hours.
- Eat at destination meal times when practical.
## Arrival day
- Westward evening arrival: go outside in daylight if any is left, stay up until the planned bedtime (a 20-minute nap before the cut-off is fine).
- Eastward morning arrival: follow the seek/avoid light windows; if you must work, put bright tasks in the seek window.
## Coming home
The return trip is a new shift in the opposite direction. Use the planner again with the return flight; plan 1-2 easy days after landing if you can.
## Business traveler checklist
- [ ] Planner run with real flight times
- [ ] Calendar: no critical meetings in the body's night
- [ ] Hotel: blackout curtains or eye mask; ask for a quiet room
- [ ] Light: sunglasses for avoid windows, a walk or a light box for seek windows
- [ ] Medication timing checked with a pharmacist
FILE:templates/jet-lag-plan.md
# Jet Lag Plan - <traveler> - <origin> to <destination>
**Flight:** <depart local> -> <arrive local> (<hours> h) **Time difference:** <+/- h> **Strategy:** <advance / delay / stay on home time>
**Usual sleep:** <bedtime>-<wake> **Pre-trip shift:** <h> **Expected days to adjust:** <n>
## Before the trip
| Date | Sleep | Bright light | Avoid light | Notes |
|---|---|---|---|---|
| | | | | |
## Flight
- Sleep on board: <times or "stay awake">
- Meals: <destination times>
- Watch set to destination time: [ ]
## At the destination
| Date | Sleep | Bright light | Avoid light | Caffeine until | Naps end by | Key events |
|---|---|---|---|---|---|---|
| | | | | | | |
## Packing
- [ ] Eye mask and ear plugs - [ ] Sunglasses - [ ] Water bottle - [ ] Medication schedule (checked with a professional)
## Return
- Shift: <h>, about <n> days to readjust; easy days planned: <dates>
FILE:examples/istanbul-to-los-angeles.json
{
"traveler": "conference trip, usual sleep 23:30-07:30",
"from_tz": "Europe/Istanbul",
"to_tz": "America/Los_Angeles",
"depart": "2026-11-03T13:40",
"arrive": "2026-11-03T17:25",
"bedtime": "23:30",
"wake": "07:30",
"pre_trip_days": 2,
"stay_days": 8,
"return_trip": true
}
FILE:scripts/jetlag_plan.py
#!/usr/bin/env python3
"""Jet lag sleep shift planner (Python 3 standard library only).
Input: a trip JSON file (or the same fields as command-line flags):
{"from_tz": "Europe/Istanbul", "to_tz": "America/Los_Angeles",
"depart": "2026-11-03T13:40", "arrive": "2026-11-03T17:25",
"bedtime": "23:30", "wake": "07:30", "pre_trip_days": 2, "stay_days": 8}
Time zones: IANA names (zoneinfo, DST-aware; needs the system tz database or the tzdata
package) or fixed offsets like "UTC+3", "+05:30", "-8". depart is local time at the origin,
arrive is local time at the destination.
Model (rules of thumb used by sleep clinics, not a medical device):
- shift = destination offset - origin offset, normalized to -12..+12 h (+ = east).
- the body clock moves about 1 h/day when advancing (eastward) and 1.5 h/day when
delaying (westward); for big eastward shifts the planner picks the direction that
takes fewer days (often delaying "the long way round").
- optional pre-trip shift: 1 h/day for pre_trip_days, toward the destination.
- core body temperature minimum (CBTmin) ~3 h before usual wake time. Light in the 3 h
after CBTmin advances the clock, light in the 3 h before it delays the clock.
- planned sleep is a compromise: target local bedtime moved toward body time by
min(2 h, half the remaining gap). Caffeine stops 8 h and naps (max 20 min) end 7 h
before planned bedtime.
Usage:
python3 jetlag_plan.py trip.json
python3 jetlag_plan.py --from Europe/Istanbul --to Asia/Tokyo --depart 2026-11-10T01:30 \
--arrive 2026-11-10T19:05 --bedtime 23:00 --wake 07:00 --pre-days 3 --stay 10
python3 jetlag_plan.py trip.json --json
python3 jetlag_plan.py --self-test
Exit code: 0 OK, 2 bad input.
"""
import argparse
import datetime as dt
import json
import math
import re
import sys
ADVANCE_RATE = 1.0
DELAY_RATE = 1.5
class TripError(ValueError):
pass
def parse_tz(name):
s = str(name).strip()
m = re.fullmatch(r"(?:UTC|GMT)?\s*([+-])(\d{1,2})(?::?(\d{2}))?", s, re.I)
if m:
sign = 1 if m.group(1) == "+" else -1
mins = int(m.group(2)) * 60 + int(m.group(3) or 0)
if mins > 14 * 60:
raise TripError(f"offset out of range: {s!r}")
return dt.timezone(dt.timedelta(minutes=sign * mins), s)
if s.upper() in ("UTC", "GMT", "Z"):
return dt.timezone.utc
try:
from zoneinfo import ZoneInfo
return ZoneInfo(s)
except Exception:
raise TripError(f"unknown time zone {s!r}; use an IANA name like Europe/Istanbul or an offset like UTC+3")
def parse_hm(s, field):
m = re.fullmatch(r"(\d{1,2}):(\d{2})", str(s).strip())
if not m or int(m.group(1)) > 23 or int(m.group(2)) > 59:
raise TripError(f"{field} must be HH:MM, got {s!r}")
return int(m.group(1)) * 60 + int(m.group(2))
def parse_local(s, tz, field):
try:
t = dt.datetime.fromisoformat(str(s).strip())
except ValueError:
raise TripError(f"{field} must be YYYY-MM-DDTHH:MM, got {s!r}")
if t.tzinfo is not None:
t = t.replace(tzinfo=None)
return t.replace(tzinfo=tz)
def hm(mins):
mins = round(mins) % 1440
return f"{mins // 60:02d}:{mins % 60:02d}"
def offset_h(t):
return t.utcoffset().total_seconds() / 3600
def choose_direction(shift):
"""shift in -12..12 (east positive). Return (signed hours to move the body, rate, label)."""
if shift == 0:
return 0.0, ADVANCE_RATE, "none"
if shift > 0:
adv_days = math.ceil(shift / ADVANCE_RATE)
alt = shift - 24
del_days = math.ceil(-alt / DELAY_RATE)
if del_days < adv_days:
return alt, DELAY_RATE, "delay (long way round)"
return shift, ADVANCE_RATE, "advance"
del_days = math.ceil(-shift / DELAY_RATE)
alt = shift + 24
adv_days = math.ceil(alt / ADVANCE_RATE)
if adv_days < del_days:
return alt, ADVANCE_RATE, "advance (long way round)"
return shift, DELAY_RATE, "delay"
def night_overlap(start_utc, end_utc, tz, night_start=22 * 60, night_end=7 * 60):
"""Return list of (start_local, end_local) pieces of the flight inside destination nights."""
pieces = []
t = start_utc
step = dt.timedelta(minutes=5)
cur = None
while t < end_utc:
loc = t.astimezone(tz)
m = loc.hour * 60 + loc.minute
is_night = m >= night_start or m < night_end
if is_night and cur is None:
cur = loc
if not is_night and cur is not None:
pieces.append((cur, loc))
cur = None
t += step
if cur is not None:
pieces.append((cur, end_utc.astimezone(tz)))
return pieces
def overlap(a0, a1, b0, b1):
"""Minutes of overlap between [a0, a1) and [b0, b1) on a 24 h circle."""
best = 0
for k in (-1440, 0, 1440):
best += max(0, min(a1, b1 + k) - max(a0, b0 + k))
return best
def light_windows(cbt, sign, sleep_start, sleep_len):
"""Seek/avoid windows around CBTmin, moved or clipped to waking hours.
sign > 0 (advance): seek 3 h after CBTmin, avoid 3 h before; sign < 0 (delay): the reverse.
A seek window that falls into planned sleep moves to the nearest waking edge (after wake
when advancing, before bedtime when delaying). Avoid windows are clipped to waking time."""
sleep_end = sleep_start + sleep_len
if sign > 0:
seek, avoid = (cbt, cbt + 180), (cbt - 180, cbt)
if overlap(seek[0], seek[1], sleep_start, sleep_end):
seek = (sleep_end, sleep_end + 180)
else:
seek, avoid = (cbt - 180, cbt), (cbt, cbt + 180)
if overlap(seek[0], seek[1], sleep_start, sleep_end):
seek = (sleep_start - 180, sleep_start)
ov = overlap(avoid[0], avoid[1], sleep_start, sleep_end)
if ov >= 180:
avoid_s = "asleep"
elif ov:
# keep the waking part of the avoid window
a0, a1 = avoid
if overlap(a0, a0 + 1, sleep_start, sleep_end):
a0 = a1 - (180 - ov)
else:
a1 = a0 + (180 - ov)
avoid_s = f"{hm(a0)}-{hm(a1)}"
else:
avoid_s = f"{hm(avoid[0])}-{hm(avoid[1])}"
return f"{hm(seek[0])}-{hm(seek[1])}", avoid_s
def plan(trip):
for k in ("from_tz", "to_tz", "depart", "arrive"):
if not trip.get(k):
raise TripError(f"missing {k}")
ftz, ttz = parse_tz(trip["from_tz"]), parse_tz(trip["to_tz"])
dep = parse_local(trip["depart"], ftz, "depart")
arr = parse_local(trip["arrive"], ttz, "arrive")
if arr.astimezone(dt.timezone.utc) <= dep.astimezone(dt.timezone.utc):
raise TripError("arrive must be after depart (check the dates and time zones)")
bed = parse_hm(trip.get("bedtime", "23:00"), "bedtime")
wake = parse_hm(trip.get("wake", "07:00"), "wake")
sleep_len = (wake - bed) % 1440
if not 4 * 60 <= sleep_len <= 12 * 60:
raise TripError("bedtime to wake must be 4-12 hours")
pre = int(trip.get("pre_trip_days", 0))
stay = int(trip.get("stay_days", 7))
if pre < 0 or pre > 4 or stay < 1:
raise TripError("pre_trip_days must be 0-4 and stay_days at least 1")
shift = offset_h(arr) - offset_h(dep.astimezone(ftz))
shift = ((shift + 12) % 24) - 12 if abs(shift) > 12 else shift
if shift == -12:
shift = 12.0
move, rate, direction = choose_direction(shift)
sign = 1 if move > 0 else -1
flags = []
if abs(shift) <= 2:
flags.append("SMALL_SHIFT: 2 h or less; most people adapt within a day, keep usual habits on local time")
if stay <= 2 and abs(shift) >= 3:
flags.append("SHORT_TRIP: 2 days or fewer; consider staying on home time and scheduling meetings inside your home daytime")
if "long way round" in direction:
flags.append(f"LONG_WAY_ROUND: a {shift:+g} h shift is planned as {move:+g} h, which usually takes fewer days")
pre_used = min(pre, int(abs(move))) if move else 0
pre_days = []
for i in range(1, pre_used + 1):
b = bed - sign * 60 * i
cbt = wake - 180 - sign * 60 * i
seek_s, avoid_s = light_windows(cbt, sign, b, sleep_len)
pre_days.append({"day": f"pre {i - pre_used - 1}", "date": str((dep.date() - dt.timedelta(days=pre_used - i + 1))),
"sleep": f"{hm(b)}-{hm(b + sleep_len)}", "seek_light": seek_s,
"avoid_light": avoid_s, "clock": "home time"})
body = sign * pre_used # hours already moved toward destination
total = abs(move)
days_needed = math.ceil(max(0.0, total - pre_used) / rate) if move else 0
days = []
d = 0
while True:
remaining = move - body # signed hours the body is still away from local time
gap = abs(remaining)
comp = min(120, gap * 60 / 2)
# remaining > 0: body clock is behind local time, so it wants to sleep later (and vice versa)
b = bed + (comp if remaining > 0 else -comp) if gap else bed
cbt_local = (wake - 180) + remaining * 60
if gap < 0.5:
seek_s, avoid_s = "daylight as usual", "-"
else:
seek_s, avoid_s = light_windows(cbt_local, sign, b, sleep_len)
if remaining > 0:
status = f"{gap:g} h behind local time"
elif remaining < 0:
status = f"{gap:g} h ahead of local time"
else:
status = "adjusted"
days.append({"day": d, "date": str(arr.date() + dt.timedelta(days=d)), "body_clock": status,
"sleep": f"{hm(b)}-{hm(b + sleep_len)}", "seek_light": seek_s, "avoid_light": avoid_s,
"caffeine_until": hm(b - 480), "naps_end_by": hm(b - 420)})
if gap == 0 or d + 1 >= stay:
break
body = body + sign * min(rate, gap)
d += 1
flight_h = (arr.astimezone(dt.timezone.utc) - dep.astimezone(dt.timezone.utc)).total_seconds() / 3600
nights = night_overlap(dep.astimezone(dt.timezone.utc), arr.astimezone(dt.timezone.utc), ttz)
nights = [(a, b) for a, b in nights if (b - a).total_seconds() >= 3600]
if nights:
inflight = "sleep during destination night: " + "; ".join(f"{a:%a %H:%M}-{b:%H:%M}" for a, b in nights)
else:
inflight = "flight is during destination daytime: stay awake, get daylight/screen light, at most a 20-minute nap"
res = {"from_tz": str(trip["from_tz"]), "to_tz": str(trip["to_tz"]), "shift_h": shift, "plan_move_h": move,
"direction": direction, "rate_h_per_day": rate, "pre_trip_shift_h": pre_used,
"days_to_adjust_after_arrival": days_needed, "flight_h": round(flight_h, 2),
"arrive_local": arr.strftime("%Y-%m-%d %H:%M"), "in_flight": inflight, "flags": flags,
"pre_trip": pre_days, "days": days}
if trip.get("return_trip"):
back, brate, bdir = choose_direction(-shift)
res["return"] = {"shift_h": -shift, "direction": bdir,
"days_to_adjust": math.ceil(abs(back) / brate) if back else 0}
return res
def to_markdown(r):
out = [f"# Jet lag plan: {r['from_tz']} -> {r['to_tz']}", "",
f"- Time difference: {r['shift_h']:+g} h ({'east' if r['shift_h'] > 0 else 'west' if r['shift_h'] < 0 else 'none'}); "
f"plan: {r['direction']} {abs(r['plan_move_h']):g} h at about {r['rate_h_per_day']:g} h/day",
f"- Pre-trip shift: {r['pre_trip_shift_h']} h; about {r['days_to_adjust_after_arrival']} day(s) to adjust after arrival",
f"- Flight: {r['flight_h']:g} h, arriving {r['arrive_local']} local; {r['in_flight']}"]
if "return" in r:
out.append(f"- Return trip: {r['return']['shift_h']:+g} h, {r['return']['direction']}, about {r['return']['days_to_adjust']} day(s) to readjust")
for f in r["flags"]:
out.append(f"- **{f.split(':')[0]}**:{f.split(':', 1)[1]}")
if r["pre_trip"]:
out += ["", "## Before you fly (home time)", "| Day | Date | Sleep | Seek bright light | Avoid bright light |", "|---|---|---|---|---|"]
for p in r["pre_trip"]:
out.append(f"| {p['day']} | {p['date']} | {p['sleep']} | {p['seek_light']} | {p['avoid_light']} |")
out += ["", "## At the destination (local time)",
"| Day | Date | Body clock | Sleep | Seek bright light | Avoid bright light | Caffeine until | Naps end by |",
"|---|---|---|---|---|---|---|---|"]
for d in r["days"]:
out.append(f"| {d['day']} | {d['date']} | {d['body_clock']} | {d['sleep']} | {d['seek_light']} | {d['avoid_light']} | {d['caffeine_until']} | {d['naps_end_by']} |")
out += ["", "Light windows that fall inside your sleep time can be skipped; use sunglasses outdoors during 'avoid' windows.",
"Rules of thumb only. Ask a doctor or pharmacist before using melatonin or sleep medication."]
return "\n".join(out)
def self_test():
cases = []
def ok(name, cond):
cases.append((name, bool(cond)))
base = {"from_tz": "Europe/Istanbul", "to_tz": "America/Los_Angeles", "depart": "2026-11-03T13:40",
"arrive": "2026-11-03T17:25", "bedtime": "23:30", "wake": "07:30", "pre_trip_days": 2, "stay_days": 10}
ok("fixed offset parse", parse_tz("UTC+3").utcoffset(None) == dt.timedelta(hours=3) and parse_tz("+05:30").utcoffset(None) == dt.timedelta(hours=5, minutes=30))
ok("negative offset parse", parse_tz("-8").utcoffset(None) == dt.timedelta(hours=-8))
r = plan(base)
ok("IST->LA after US DST ends is -11 h", r["shift_h"] == -11)
ok("westward plan delays", r["direction"] == "delay" and r["plan_move_h"] == -11)
ok("pre-trip 2 h used", r["pre_trip_shift_h"] == 2 and len(r["pre_trip"]) == 2)
ok("days to adjust ceil(9/1.5)=6", r["days_to_adjust_after_arrival"] == 6)
ok("pre-trip bedtime later for westward", r["pre_trip"][0]["sleep"].startswith("00:30") and r["pre_trip"][1]["sleep"].startswith("01:30"))
ok("day 0 body 9 h ahead", r["days"][0]["body_clock"] == "9 h ahead of local time")
ok("day 0 compromise bedtime 21:30", r["days"][0]["sleep"] == "21:30-05:30")
ok("delay: seek light before CBTmin", r["days"][0]["seek_light"] == "16:30-19:30")
ok("delay: avoid window clipped at bedtime", r["days"][0]["avoid_light"] == "19:30-21:30")
ok("delay: seek window moved before bedtime", r["days"][3]["seek_light"] == "18:30-21:30" and r["days"][3]["avoid_light"] == "asleep")
ok("pre-trip delay light in the evening", r["pre_trip"][0]["seek_light"] == "21:30-00:30")
ok("overlap on circle", overlap(1380, 1500, 0, 60) == 60 and overlap(600, 700, 0, 60) == 0)
ok("plan ends adjusted", r["days"][-1]["body_clock"] == "adjusted" and r["days"][-1]["sleep"] == "23:30-07:30")
ok("plan length 7 days (0..6)", len(r["days"]) == 7)
ok("flight of 14.75 h", r["flight_h"] == 14.75)
r2 = plan(dict(base, to_tz="America/Los_Angeles", depart="2026-10-20T13:40", arrive="2026-10-20T16:25"))
ok("IST->LA during US DST is -10 h", r2["shift_h"] == -10)
r3 = plan(dict(base, to_tz="Asia/Tokyo", depart="2026-11-10T01:30", arrive="2026-11-10T19:05", pre_trip_days=3))
ok("IST->Tokyo +6 advance", r3["shift_h"] == 6 and r3["direction"] == "advance" and r3["days_to_adjust_after_arrival"] == 3)
ok("advance: seek light moved to after wake", r3["days"][0]["seek_light"] == "09:00-12:00" and r3["days"][0]["avoid_light"] == "asleep")
ok("pre-trip bedtime earlier for eastward", r3["pre_trip"][0]["sleep"].startswith("22:30"))
ok("+11 east goes long way round", choose_direction(11) == (-13, DELAY_RATE, "delay (long way round)"))
ok("+9 east stays advance", choose_direction(9)[2] == "advance")
ok("-12 normalized to +12 then delay -12", choose_direction(12)[0] == -12)
r4 = plan(dict(base, to_tz="Europe/Berlin", depart="2026-11-03T08:00", arrive="2026-11-03T09:00", stay_days=2))
ok("small shift flag", any(f.startswith("SMALL_SHIFT") for f in r4["flags"]))
r5 = plan(dict(base, stay_days=2))
ok("short trip flag", any(f.startswith("SHORT_TRIP") for f in r5["flags"]) and len(r5["days"]) == 2)
ok("in-flight sleep in LA night 02:40-07:00", r["in_flight"].endswith("Tue 02:40-07:00"))
ok("Tokyo daytime flight: stay awake", "destination daytime" in r3["in_flight"])
ok("caffeine 8 h before bed", r["days"][-1]["caffeine_until"] == "15:30" and r["days"][-1]["naps_end_by"] == "16:30")
for bad, label in ((dict(base, to_tz="Mars/Olympus"), "unknown tz rejected"), (dict(base, bedtime="25:00"), "bad bedtime rejected"),
(dict(base, arrive="2026-11-02T10:00"), "arrival before departure rejected"), (dict(base, pre_trip_days=9), "pre-trip >4 rejected")):
try:
plan(bad)
ok(label, False)
except TripError:
ok(label, True)
ok("hm wraps midnight", hm(-30) == "23:30" and hm(1500) == "01:00")
passed = sum(c for _, c in cases)
for name, c in cases:
print(("PASS " if c else "FAIL ") + name)
print(f"{passed}/{len(cases)} passed")
return 0 if passed == len(cases) else 1
def main(argv=None):
ap = argparse.ArgumentParser(description="Plan sleep and light timing to beat jet lag.")
ap.add_argument("file", nargs="?", help="trip JSON")
ap.add_argument("--from", dest="from_tz")
ap.add_argument("--to", dest="to_tz")
ap.add_argument("--depart")
ap.add_argument("--arrive")
ap.add_argument("--bedtime")
ap.add_argument("--wake")
ap.add_argument("--pre-days", type=int, dest="pre_trip_days")
ap.add_argument("--stay", type=int, dest="stay_days")
ap.add_argument("--json", action="store_true")
ap.add_argument("--self-test", action="store_true")
a = ap.parse_args(argv)
if a.self_test:
return self_test()
try:
trip = json.load(open(a.file, encoding="utf-8")) if a.file else {}
for k in ("from_tz", "to_tz", "depart", "arrive", "bedtime", "wake", "pre_trip_days", "stay_days"):
if getattr(a, k) is not None:
trip[k] = getattr(a, k)
r = plan(trip)
except (OSError, TripError, ValueError) as e:
print(f"error: {e}", file=sys.stderr)
return 2
print(json.dumps(r, indent=2) if a.json else to_markdown(r))
return 0
if __name__ == "__main__":
sys.exit(main())