#!/usr/bin/env bash
# Battery Calibration Script for Arch Linux on MacBook Air
# Helps safely discharge/charge battery to recalibrate SMC.

LOGFILE="$HOME/battery_calibration.log"
THRESHOLD_SHUTDOWN=2   # % at which system will auto-shutdown
THRESHOLD_WARN1=10
THRESHOLD_WARN2=5

get_capacity() {
    cat /sys/class/power_supply/BAT0/capacity
}

get_status() {
    cat /sys/class/power_supply/BAT0/status
}

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $*" | tee -a "$LOGFILE"
}

log "=== Starting battery calibration session ==="

while true; do
    CAPACITY=$(get_capacity)
    STATUS=$(get_status)

    log "Battery: $CAPACITY% | Status: $STATUS"

    if [[ "$STATUS" == "Discharging" ]]; then
        if (( CAPACITY <= THRESHOLD_WARN1 && CAPACITY > THRESHOLD_WARN2 )); then
            notify-send "Battery Calibration" "Battery low: $CAPACITY%. Save work."
        elif (( CAPACITY <= THRESHOLD_WARN2 && CAPACITY > THRESHOLD_SHUTDOWN )); then
            notify-send "Battery Calibration" "Battery critical: $CAPACITY%. Shutdown soon."
        elif (( CAPACITY <= THRESHOLD_SHUTDOWN )); then
            log "Battery reached $CAPACITY%. Shutting down for full discharge..."
            systemctl poweroff
        fi
    fi

    sleep 60  # check every minute
done