#!/bin/sh
# Bananarchy Dual-SIM & QMI UIM Provisioning Helper for Qualcomm MSM8905/MSM8909
set -eu

CONF_FILE="/etc/conf.d/msm-modem-uim-selection"
if [ -r "$CONF_FILE" ]; then
  # shellcheck disable=SC1090
  . "$CONF_FILE"
fi

SIM_WAIT_TIME="${SIM_WAIT_TIME:-${sim_wait_time:-4}}"
PREFERRED_SIM_SLOT="${PREFERRED_SIM_SLOT:-${preferred_sim_slot:-1}}"
QMICLI_MODEM=""

detect_qmicli_modem() {
  if ! command -v qmicli >/dev/null 2>&1; then
    return 1
  fi
  if [ -e "/dev/modem" ]; then
    QMICLI_MODEM="qmicli --silent -d /dev/modem"
    return 0
  elif [ -e "/dev/wwan0qmi0" ]; then
    QMICLI_MODEM="qmicli --silent -d /dev/wwan0qmi0 --device-open-qmi"
    return 0
  elif qmicli --silent -pd qrtr://0 --uim-noop >/dev/null 2>&1; then
    QMICLI_MODEM="qmicli --silent -pd qrtr://0"
    return 0
  fi
  return 1
}

wait_for_qmicli_modem() {
  max_wait="${1:-45}"
  count=0
  while [ "$count" -lt "$max_wait" ]; do
    if detect_qmicli_modem; then
      return 0
    fi
    sleep 1
    count=$((count + 1))
  done
  return 1
}

# Parse `qmicli --uim-get-card-status` into shell-safe KEY=VALUE lines
parse_uim_card_status() {
  raw_status="$1"
  pref_slot="$2"
  printf "%s\n" "$raw_status" | awk -v pref="$pref_slot" '
    BEGIN {
      prim_slot = 0
      prim_app = 0
      cur_slot = 0
      in_app = 0
      for (s = 1; s <= 2; s++) {
        cstate[s] = "absent"
        rawstate[s] = "absent"
        upin_state[s] = "not-initialized"
        upin_ret[s] = 0
        upuk_ret[s] = 0
        app_type[s] = "none"
        app_state[s] = "none"
        aid[s] = ""
        pin1_state[s] = "not-initialized"
        pin1_ret[s] = 0
        puk1_ret[s] = 0
      }
    }
    /Primary GW:/ {
      if ($0 ~ /slot \x27[0-9]+\x27/) {
        line = $0
        sub(/.*slot \x27/, "", line)
        sub(/\x27.*/, "", line)
        prim_slot = line + 0
      }
      if ($0 ~ /application \x27[0-9]+\x27/) {
        line = $0
        sub(/.*application \x27/, "", line)
        sub(/\x27.*/, "", line)
        prim_app = line + 0
      }
    }
    /^[[:space:]]*Slot \[[0-9]+\]:/ {
      line = $0
      sub(/.*Slot \[/, "", line)
      sub(/\].*/, "", line)
      cur_slot = line + 0
      in_app = 0
      next
    }
    cur_slot >= 1 && cur_slot <= 2 {
      if ($0 ~ /^[[:space:]]*Application \[[0-9]+\]:/) {
        in_app = 1
        next
      }
      if (!in_app && $0 ~ /Card state:/) {
        line = $0
        sub(/.*Card state: \x27/, "", line)
        sub(/\x27.*/, "", line)
        rawstate[cur_slot] = line
        if (line == "present") cstate[cur_slot] = "present"
        else if (line == "absent" || line ~ /no-atr-received/) cstate[cur_slot] = "absent"
        else cstate[cur_slot] = "error"
      }
      if (!in_app && $0 ~ /UPIN state:/) {
        line = $0
        sub(/.*UPIN state: \x27/, "", line)
        sub(/\x27.*/, "", line)
        upin_state[cur_slot] = line
      }
      if (!in_app && $0 ~ /UPIN retries:/) {
        line = $0
        sub(/.*UPIN retries: \x27/, "", line)
        sub(/\x27.*/, "", line)
        upin_ret[cur_slot] = line + 0
      }
      if (!in_app && $0 ~ /UPUK retries:/) {
        line = $0
        sub(/.*UPUK retries: \x27/, "", line)
        sub(/\x27.*/, "", line)
        upuk_ret[cur_slot] = line + 0
      }
      if (in_app && $0 ~ /Application type:/) {
        line = $0
        sub(/.*Application type: \x27/, "", line)
        sub(/\x27.*/, "", line)
        if (line ~ /^usim/) {
          app_type[cur_slot] = "usim"
          want_aid[cur_slot] = 2
        } else if (line ~ /^sim/ && app_type[cur_slot] != "usim") {
          app_type[cur_slot] = "sim"
          want_aid[cur_slot] = 1
        } else {
          want_aid[cur_slot] = 0
        }
      }
      if (in_app && $0 ~ /Application state:/ && want_aid[cur_slot] > 0) {
        line = $0
        sub(/.*Application state: \x27/, "", line)
        sub(/\x27.*/, "", line)
        app_state[cur_slot] = line
      }
      if (in_app && $0 ~ /Application ID:/ && want_aid[cur_slot] > 0) {
        need_aid_line[cur_slot] = 1
        next
      }
      if (in_app && need_aid_line[cur_slot] == 1) {
        line = $0
        gsub(/^[[:space:]]+|[[:space:]]+$/, "", line)
        if (line != "") {
          aid[cur_slot] = line
        }
        need_aid_line[cur_slot] = 0
      }
      if (in_app && $0 ~ /PIN1 state:/ && want_aid[cur_slot] > 0) {
        line = $0
        sub(/.*PIN1 state: \x27/, "", line)
        sub(/\x27.*/, "", line)
        pin1_state[cur_slot] = line
      }
      if (in_app && $0 ~ /PIN1 retries:/ && want_aid[cur_slot] > 0) {
        line = $0
        sub(/.*PIN1 retries: \x27/, "", line)
        sub(/\x27.*/, "", line)
        pin1_ret[cur_slot] = line + 0
      }
      if (in_app && $0 ~ /PUK1 retries:/ && want_aid[cur_slot] > 0) {
        line = $0
        sub(/.*PUK1 retries: \x27/, "", line)
        sub(/\x27.*/, "", line)
        puk1_ret[cur_slot] = line + 0
      }
    }
    END {
      printf "PREFERRED_SLOT=%d\n", (pref == 2 ? 2 : 1)
      printf "PRIMARY_GW_SLOT=%d\n", prim_slot
      printf "PRIMARY_GW_APP=%d\n", prim_app
      for (s = 1; s <= 2; s++) {
        printf "SLOT%d_STATE=%s\n", s, cstate[s]
        printf "SLOT%d_RAW_STATE=%s\n", s, rawstate[s]
        printf "SLOT%d_APP_TYPE=%s\n", s, app_type[s]
        printf "SLOT%d_APP_STATE=%s\n", s, app_state[s]
        printf "SLOT%d_AID=%s\n", s, aid[s]
        printf "SLOT%d_PIN1_STATE=%s\n", s, pin1_state[s]
        printf "SLOT%d_PIN1_RETRIES=%d\n", s, pin1_ret[s]
        printf "SLOT%d_PUK1_RETRIES=%d\n", s, puk1_ret[s]
        printf "SLOT%d_UPIN_STATE=%s\n", s, upin_state[s]
        printf "SLOT%d_UPIN_RETRIES=%d\n", s, upin_ret[s]
        printf "SLOT%d_UPUK_RETRIES=%d\n", s, upuk_ret[s]
      }
    }
  '
}

save_preferred_slot() {
  target_slot="$1"
  if [ -f "$CONF_FILE" ]; then
    if grep -q "^preferred_sim_slot=" "$CONF_FILE"; then
      sed -i "s/^preferred_sim_slot=.*/preferred_sim_slot=$target_slot/" "$CONF_FILE"
    else
      printf "\npreferred_sim_slot=%s\n" "$target_slot" >> "$CONF_FILE"
    fi
  else
    printf "sim_wait_time=4\npreferred_sim_slot=%s\n" "$target_slot" > "$CONF_FILE"
  fi
}

provision_slot() {
  req_slot="$1"
  wait_secs="$2"

  if ! wait_for_qmicli_modem "$wait_secs"; then
    echo "No modem available." >&2
    return 2
  fi

  QMI_CARDS="$($QMICLI_MODEM --uim-get-card-status 2>/dev/null || true)"
  count=0
  while ! printf "%s" "$QMI_CARDS" | grep -Fq "Card state: 'present'"; do
    if [ "$count" -ge "$SIM_WAIT_TIME" ]; then
      echo "No SIM detected after $SIM_WAIT_TIME seconds."
      return 0
    fi
    sleep 1
    count=$((count + 1))
    QMI_CARDS="$($QMICLI_MODEM --uim-get-card-status 2>/dev/null || true)"
  done

  eval "$(parse_uim_card_status "$QMI_CARDS" "$req_slot")"

  chosen_slot=""
  chosen_aid=""
  if [ "$req_slot" = "2" ]; then
    if [ "$SLOT2_STATE" = "present" ] && [ -n "$SLOT2_AID" ]; then
      chosen_slot="2"
      chosen_aid="$SLOT2_AID"
    elif [ "$SLOT1_STATE" = "present" ] && [ -n "$SLOT1_AID" ]; then
      chosen_slot="1"
      chosen_aid="$SLOT1_AID"
    fi
  else
    if [ "$SLOT1_STATE" = "present" ] && [ -n "$SLOT1_AID" ]; then
      chosen_slot="1"
      chosen_aid="$SLOT1_AID"
    elif [ "$SLOT2_STATE" = "present" ] && [ -n "$SLOT2_AID" ]; then
      chosen_slot="2"
      chosen_aid="$SLOT2_AID"
    fi
  fi

  if [ -z "$chosen_slot" ] || [ -z "$chosen_aid" ]; then
    echo "No valid USIM/SIM application found on any slot."
    return 0
  fi

  if [ "$PRIMARY_GW_SLOT" != "0" ]; then
    $QMICLI_MODEM --uim-change-provisioning-session='activate=no,session-type=primary-gw-provisioning' >/dev/null 2>&1 || true
  fi

  echo "Selecting AID $chosen_aid on slot $chosen_slot"
  $QMICLI_MODEM --uim-change-provisioning-session="slot=$chosen_slot,activate=yes,session-type=primary-gw-provisioning,aid=$chosen_aid" >/dev/null
  return $?
}

cmd="${1:-boot}"

case "$cmd" in
  boot)
    if command -v systemd-notify >/dev/null 2>&1; then
      trap '[ $? -eq 0 ] && systemd-notify --ready' EXIT
    fi
    case "$(cat /sys/devices/soc0/machine 2>/dev/null || true)" in
      APQ*)
        echo "Skipping SIM configuration on APQ SoC."
        exit 0
        ;;
    esac
    provision_slot "$PREFERRED_SIM_SLOT" 45
    exit $?
    ;;

  status)
    if ! detect_qmicli_modem; then
      echo "MODEM_AVAILABLE=0"
      echo "PREFERRED_SLOT=$PREFERRED_SIM_SLOT"
      exit 0
    fi
    QMI_CARDS="$($QMICLI_MODEM --uim-get-card-status 2>/dev/null || true)"
    if [ -z "$QMI_CARDS" ]; then
      echo "MODEM_AVAILABLE=0"
      echo "PREFERRED_SLOT=$PREFERRED_SIM_SLOT"
      exit 0
    fi
    echo "MODEM_AVAILABLE=1"
    parse_uim_card_status "$QMI_CARDS" "$PREFERRED_SIM_SLOT"
    exit 0
    ;;

  switch)
    target="${2:-1}"
    if [ "$target" != "1" ] && [ "$target" != "2" ]; then
      echo "Invalid slot: $target (must be 1 or 2)" >&2
      exit 1
    fi
    save_preferred_slot "$target"
    SIM_WAIT_TIME=2
    provision_slot "$target" 5
    if command -v rc-service >/dev/null 2>&1; then
      rc-service modemmanager restart >/dev/null 2>&1 || true
    elif command -v systemctl >/dev/null 2>&1; then
      systemctl restart ModemManager >/dev/null 2>&1 || true
    fi
    exit 0
    ;;

  verify-pin)
    slot="${2:-1}"
    pin="${3:-}"
    if [ -z "$pin" ]; then
      echo "Missing PIN" >&2
      exit 1
    fi
    sim_id="$(mmcli -m any 2>/dev/null | grep -oE 'SIM/[0-9]+' | head -n1 | cut -d'/' -f2 || true)"
    if [ -n "$sim_id" ] && mmcli -i "$sim_id" --pin="$pin" >/dev/null 2>&1; then
      exit 0
    fi
    if detect_qmicli_modem; then
      if $QMICLI_MODEM --uim-verify-pin="PIN1,$pin,session-type=primary-gw-provisioning" >/dev/null 2>&1; then
        exit 0
      fi
      if $QMICLI_MODEM --uim-verify-pin="PIN1,$pin,session-type=card-slot-$slot" >/dev/null 2>&1; then
        exit 0
      fi
    fi
    exit 1
    ;;

  unblock-puk)
    slot="${2:-1}"
    puk="${3:-}"
    newpin="${4:-}"
    if [ -z "$puk" ] || [ -z "$newpin" ]; then
      echo "Missing PUK or new PIN" >&2
      exit 1
    fi
    sim_id="$(mmcli -m any 2>/dev/null | grep -oE 'SIM/[0-9]+' | head -n1 | cut -d'/' -f2 || true)"
    if [ -n "$sim_id" ] && mmcli -i "$sim_id" --puk="$puk" --pin="$newpin" >/dev/null 2>&1; then
      exit 0
    fi
    if detect_qmicli_modem; then
      if $QMICLI_MODEM --uim-unblock-pin="PIN1,$puk,$newpin,session-type=primary-gw-provisioning" >/dev/null 2>&1; then
        exit 0
      fi
      if $QMICLI_MODEM --uim-unblock-pin="PIN1,$puk,$newpin,session-type=card-slot-$slot" >/dev/null 2>&1; then
        exit 0
      fi
    fi
    exit 1
    ;;

  set-pin-lock)
    slot="${2:-1}"
    mode="${3:-enable}"
    pin="${4:-}"
    if [ -z "$pin" ] || { [ "$mode" != "enable" ] && [ "$mode" != "disable" ]; }; then
      echo "Usage: $0 set-pin-lock <1|2> <enable|disable> <pin>" >&2
      exit 1
    fi
    sim_id="$(mmcli -m any 2>/dev/null | grep -oE 'SIM/[0-9]+' | head -n1 | cut -d'/' -f2 || true)"
    if [ -n "$sim_id" ]; then
      if [ "$mode" = "enable" ] && mmcli -i "$sim_id" --enable-pin --pin="$pin" >/dev/null 2>&1; then
        exit 0
      elif [ "$mode" = "disable" ] && mmcli -i "$sim_id" --disable-pin --pin="$pin" >/dev/null 2>&1; then
        exit 0
      fi
    fi
    if detect_qmicli_modem; then
      if $QMICLI_MODEM --uim-set-pin-protection="PIN1,$mode,$pin,session-type=primary-gw-provisioning" >/dev/null 2>&1; then
        exit 0
      fi
      if $QMICLI_MODEM --uim-set-pin-protection="PIN1,$mode,$pin,session-type=card-slot-$slot" >/dev/null 2>&1; then
        exit 0
      fi
    fi
    exit 1
    ;;

  change-pin)
    slot="${2:-1}"
    oldpin="${3:-}"
    newpin="${4:-}"
    if [ -z "$oldpin" ] || [ -z "$newpin" ]; then
      echo "Usage: $0 change-pin <1|2> <oldpin> <newpin>" >&2
      exit 1
    fi
    sim_id="$(mmcli -m any 2>/dev/null | grep -oE 'SIM/[0-9]+' | head -n1 | cut -d'/' -f2 || true)"
    if [ -n "$sim_id" ] && mmcli -i "$sim_id" --change-pin="$newpin" --pin="$oldpin" >/dev/null 2>&1; then
      exit 0
    fi
    if detect_qmicli_modem; then
      if $QMICLI_MODEM --uim-change-pin="PIN1,$oldpin,$newpin,session-type=primary-gw-provisioning" >/dev/null 2>&1; then
        exit 0
      fi
      if $QMICLI_MODEM --uim-change-pin="PIN1,$oldpin,$newpin,session-type=card-slot-$slot" >/dev/null 2>&1; then
        exit 0
      fi
    fi
    exit 1
    ;;

  imei)
    imei1=""
    imei2=""
    imei_sv=""
    if detect_qmicli_modem; then
      dms_ids="$($QMICLI_MODEM --dms-get-ids 2>/dev/null || true)"
      imei1="$(printf "%s\n" "$dms_ids" | sed -n "s/.*IMEI: '\([0-9]\{14,16\}\)'/\1/p" | head -n1)"
      imei_sv="$(printf "%s\n" "$dms_ids" | sed -n "s/.*IMEI SV: '\([^']*\)'/\1/p" | head -n1)"
    fi
    if [ -z "$imei1" ]; then
      imei1="$(mmcli -m any -K 2>/dev/null | awk -F': ' '/modem\.3gpp\.imei/ {print $2; exit}')"
    fi
    # Query secondary AT channel (/dev/wwan0at1) if present
    if [ -c "/dev/wwan0at1" ]; then
      at_out="$(timeout 1 sh -c '
        stty -F /dev/wwan0at1 raw -echo 115200 2>/dev/null || true
        (cat /dev/wwan0at1 & pid=$!; printf "AT+CGSN\r\n" > /dev/wwan0at1; sleep 0.25; kill $pid 2>/dev/null) 2>/dev/null
      ' 2>/dev/null | tr -d "\r" | grep -oE '^[0-9]{15}$' | head -n1 || true)"
      if [ -n "$at_out" ] && [ "$at_out" != "$imei1" ]; then
        imei2="$at_out"
      fi
    fi
    # Scan factory partitions for Luhn-valid 15-digit IMEIs (TAC 35...)
    if [ -z "$imei2" ]; then
      for part in /dev/disk/by-partlabel/traceability /dev/disk/by-partlabel/tunning /dev/disk/by-partlabel/devinfo /dev/disk/by-partlabel/oem; do
        [ -e "$part" ] || continue
        cand_list="$(strings -n 14 "$part" 2>/dev/null | grep -oE '35[0-9]{13}' | awk '
          {
            val = $0
            sum = 0
            for (i = 1; i <= 14; i++) {
              d = substr(val, i, 1) + 0
              if (i % 2 == 0) {
                d *= 2
                if (d > 9) d -= 9
              }
              sum += d
            }
            chk = (10 - (sum % 10)) % 10
            if (chk == (substr(val, 15, 1) + 0)) print val
          }
        ' || true)"
        for c in $cand_list; do
          if [ -z "$imei1" ]; then
            imei1="$c"
          elif [ "$c" != "$imei1" ] && [ -z "$imei2" ]; then
            imei2="$c"
            break 2
          fi
        done
      done
    fi
    echo "IMEI1=${imei1}"
    echo "IMEI2=${imei2}"
    echo "IMEI_SV=${imei_sv}"
    ;;

  usb-tether)
    mode="${2:-status}"
    case "$mode" in
      on)
        sysctl -w net.ipv4.ip_forward=1 >/dev/null 2>&1 || true
        nft add table ip nat 2>/dev/null || true
        nft 'add chain ip nat postrouting { type nat hook postrouting priority 100 ; }' 2>/dev/null || true
        nft add rule ip nat postrouting oifname "wwan*" masquerade 2>/dev/null || true
        nft add rule ip nat postrouting oifname "wlan*" masquerade 2>/dev/null || true
        ip addr show dev usb0 2>/dev/null | grep -q "172.16.42.1" || ip addr add 172.16.42.1/16 dev usb0 2>/dev/null || true
        ip link set usb0 up 2>/dev/null || true
        echo "1" > /tmp/bananarchy_usb_tether.active
        ;;
      off)
        sysctl -w net.ipv4.ip_forward=0 >/dev/null 2>&1 || true
        nft delete table ip nat 2>/dev/null || true
        nmcli connection delete USBNetworkShare >/dev/null 2>&1 || true
        ip addr show dev usb0 2>/dev/null | grep -q "172.16.42.1" || ip addr add 172.16.42.1/16 dev usb0 2>/dev/null || true
        ip link set usb0 up 2>/dev/null || true
        rm -f /tmp/bananarchy_usb_tether.active
        ;;
      *)
        if [ -f /tmp/bananarchy_usb_tether.active ] && [ "$(sysctl -n net.ipv4.ip_forward 2>/dev/null || echo 0)" = "1" ]; then
          echo "ACTIVE=1"
        else
          echo "ACTIVE=0"
        fi
        ;;
    esac
    ;;

  at)
    port="${2:-auto}"
    shift 2 2>/dev/null || true
    at_cmd="$*"
    if [ -z "$at_cmd" ]; then
      echo "ERROR: Empty AT command"
      exit 1
    fi
    resp=""
    for candidate in "$port" /dev/wwan0at1 /dev/wwan0at0; do
      case "$candidate" in
        wwan0at0|wwan0at1)
          dev="/dev/$candidate"
          ;;
        /dev/wwan0at0|/dev/wwan0at1)
          dev="$candidate"
          ;;
        *)
          dev=""
          ;;
      esac
      if [ -n "$dev" ] && [ -c "$dev" ]; then
        resp="$(timeout 2 sh -c '
          dev="$1"
          cmd="$2"
          tmpf="/tmp/at_resp_$$.txt"
          rm -f "$tmpf"
          cat "$dev" > "$tmpf" 2>/dev/null &
          rpid=$!
          sleep 0.04
          printf "%s\r\n" "$cmd" > "$dev" 2>/dev/null || true
          i=0
          while [ "$i" -lt 12 ]; do
            if grep -qE "(^|[[:space:]])(OK|ERROR|\+CME ERROR|\+CMS ERROR)([[:space:]]|$)" "$tmpf" 2>/dev/null; then
              break
            fi
            sleep 0.08
            i=$((i + 1))
          done
          kill "$rpid" 2>/dev/null || true
          wait "$rpid" 2>/dev/null || true
          tr -d "\r" < "$tmpf" 2>/dev/null || true
          rm -f "$tmpf"
        ' _ "$dev" "$at_cmd" 2>/dev/null | sed '/^[[:space:]]*$/d' || true)"
        if [ -n "$resp" ]; then
          printf "%s\n" "$resp"
          exit 0
        fi
      fi
      if [ "$port" != "auto" ] && [ "$candidate" = "$port" ]; then
        break
      fi
    done
    mm_out="$(mmcli -m any --command="$at_cmd" 2>&1 || true)"
    if [ -n "$mm_out" ]; then
      printf "%s\n" "$mm_out" | sed "s/^response: '\(.*\)'$/\1/"
      exit 0
    fi
    echo "ERROR: No response from modem AT channel"
    exit 1
    ;;

  sim-contacts-import)
    req_slot="${2:-auto}"
    if ! wait_for_qmicli_modem 3; then
      echo "ERROR: No modem available"
      exit 1
    fi
    QMI_CARDS="$($QMICLI_MODEM --uim-get-card-status 2>/dev/null || true)"
    if [ -z "$QMI_CARDS" ]; then
      echo "ERROR: Cannot read SIM card status"
      exit 1
    fi
    eval "$(parse_uim_card_status "$QMI_CARDS" "$PREFERRED_SIM_SLOT")"

    target_slot=""
    target_aid=""
    if [ "$req_slot" = "1" ]; then
      if [ "$SLOT1_STATE" != "present" ]; then
        echo "ERROR: SIM 1 is not inserted"
        exit 1
      fi
      target_slot="1"
      target_aid="$SLOT1_AID"
    elif [ "$req_slot" = "2" ]; then
      if [ "$SLOT2_STATE" != "present" ]; then
        echo "ERROR: SIM 2 is not inserted"
        exit 1
      fi
      target_slot="2"
      target_aid="$SLOT2_AID"
    else
      if [ "$PRIMARY_GW_SLOT" = "1" ] && [ "$SLOT1_STATE" = "present" ]; then
        target_slot="1"
        target_aid="$SLOT1_AID"
      elif [ "$PRIMARY_GW_SLOT" = "2" ] && [ "$SLOT2_STATE" = "present" ]; then
        target_slot="2"
        target_aid="$SLOT2_AID"
      elif [ "$SLOT1_STATE" = "present" ]; then
        target_slot="1"
        target_aid="$SLOT1_AID"
      elif [ "$SLOT2_STATE" = "present" ]; then
        target_slot="2"
        target_aid="$SLOT2_AID"
      else
        echo "ERROR: No SIM card detected"
        exit 1
      fi
    fi

    orig_gw_slot="$PRIMARY_GW_SLOT"
    orig_gw_aid=""
    if [ "$orig_gw_slot" = "1" ]; then
      orig_gw_aid="$SLOT1_AID"
    elif [ "$orig_gw_slot" = "2" ]; then
      orig_gw_aid="$SLOT2_AID"
    fi
    switched_gw=0
    restore_gw_slot() {
      if [ "$switched_gw" = "1" ]; then
        $QMICLI_MODEM --uim-change-provisioning-session='activate=no,session-type=primary-gw-provisioning' >/dev/null 2>&1 || true
        if [ -n "$orig_gw_slot" ] && [ "$orig_gw_slot" != "0" ] && [ -n "$orig_gw_aid" ]; then
          $QMICLI_MODEM --uim-change-provisioning-session="slot=$orig_gw_slot,activate=yes,session-type=primary-gw-provisioning,aid=$orig_gw_aid" >/dev/null 2>&1 || true
        fi
        switched_gw=0
      fi
    }
    trap restore_gw_slot EXIT INT TERM

    if [ "$PRIMARY_GW_SLOT" != "$target_slot" ] && [ -n "$target_aid" ]; then
      if [ "$PRIMARY_GW_SLOT" != "0" ]; then
        $QMICLI_MODEM --uim-change-provisioning-session='activate=no,session-type=primary-gw-provisioning' >/dev/null 2>&1 || true
      fi
      if $QMICLI_MODEM --uim-change-provisioning-session="slot=$target_slot,activate=yes,session-type=primary-gw-provisioning,aid=$target_aid" >/dev/null 2>&1; then
        switched_gw=1
        sleep 1
      fi
    fi

    tmp_contacts="/tmp/sim_import_$$.tsv"
    rm -f "$tmp_contacts"
    : > "$tmp_contacts"

    # Method 1: Standard 3GPP AT+CPBS="SM" / AT+CPBR
    at_info="$("$0" at auto 'AT+CMEE=2;+CSCS="GSM";+CPBS="SM";+CPBR=?' 2>/dev/null || true)"
    max_idx="$(printf "%s\n" "$at_info" | sed -n 's/.*+CPBR:[[:space:]]*([0-9]*-\([0-9]*\)).*/\1/p' | head -n1)"
    if [ -n "$max_idx" ] && [ "$max_idx" -gt 0 ] 2>/dev/null; then
      if [ "$max_idx" -gt 500 ]; then
        max_idx=500
      fi
      start_idx=1
      while [ "$start_idx" -le "$max_idx" ]; do
        end_idx=$((start_idx + 49))
        if [ "$end_idx" -gt "$max_idx" ]; then
          end_idx="$max_idx"
        fi
        chunk="$("$0" at auto "AT+CPBR=${start_idx},${end_idx}" 2>/dev/null || true)"
        if [ -n "$chunk" ]; then
          printf "%s\n" "$chunk" | awk '
            /^\+CPBR:[[:space:]]*[0-9]+,/ {
              line = $0
              sub(/^\+CPBR:[[:space:]]*[0-9]+,[[:space:]]*"/, "", line)
              q1 = index(line, "\"")
              if (q1 <= 0) next
              num = substr(line, 1, q1 - 1)
              rest = substr(line, q1 + 1)
              sub(/^[[:space:]]*,[[:space:]]*/, "", rest)
              c2 = index(rest, ",")
              if (c2 <= 0) next
              ton = substr(rest, 1, c2 - 1) + 0
              name = substr(rest, c2 + 1)
              sub(/^[[:space:]]*"/, "", name)
              sub(/"[[:space:]]*$/, "", name)
              gsub(/[\t\r\n]/, " ", name)
              gsub(/^[[:space:]]+|[[:space:]]+$/, "", name)
              gsub(/^[[:space:]]+|[[:space:]]+$/, "", num)
              if (num == "") next
              if (ton == 145 && substr(num, 1, 1) != "+") {
                num = "+" num
              }
              if (name == "") name = num
              printf "%s\t%s\n", num, name
            }
          ' >> "$tmp_contacts"
        fi
        start_idx=$((end_idx + 1))
      done
    fi

    # Method 2: Direct QMI UIM EF_ADN (3F00:7F10:6F3A) record fallback
    if [ ! -s "$tmp_contacts" ]; then
      adn_attr="$($QMICLI_MODEM --uim-get-file-attributes=0x3F00,0x7F10,0x6F3A 2>/dev/null || true)"
      reclen="$(printf "%s\n" "$adn_attr" | awk -F"'" '/Record length:/ {print $2 + 0; exit}')"
      reccount="$(printf "%s\n" "$adn_attr" | awk -F"'" '/Record count:/ {print $2 + 0; exit}')"
      if [ -n "$reclen" ] && [ -n "$reccount" ] && [ "$reclen" -ge 14 ] 2>/dev/null && [ "$reccount" -ge 1 ] 2>/dev/null; then
        if [ "$reccount" -gt 250 ]; then
          reccount=250
        fi
        rec=1
        while [ "$rec" -le "$reccount" ]; do
          raw_rec="$($QMICLI_MODEM --uim-read-record="file=0x3F00,0x7F10,0x6F3A,record-number=${rec},record-length=${reclen}" 2>/dev/null || true)"
          if [ -n "$raw_rec" ]; then
            printf "%s\n" "$raw_rec" | awk -v rlen="$reclen" '
              function hex2val(h,   i, c, v, res) {
                res = 0
                h = toupper(h)
                for (i = 1; i <= length(h); i++) {
                  c = substr(h, i, 1)
                  v = index("0123456789ABCDEF", c) - 1
                  if (v < 0) return -1
                  res = res * 16 + v
                }
                return res
              }
              function bcd_digit(n) {
                if (n >= 0 && n <= 9) return "" n
                if (n == 10) return "*"
                if (n == 11) return "#"
                return ""
              }
              /^[[:space:]]*([0-9A-Fa-f]{2}:)+[0-9A-Fa-f]{2}[[:space:]]*$/ {
                line = $0
                gsub(/^[[:space:]]+|[[:space:]]+$/, "", line)
                n = split(line, hex, ":")
                if (n < 14) next
                alpha_len = n - 14
                bcd_len = hex2val(hex[alpha_len + 1])
                ton_npi = hex2val(hex[alpha_len + 2])
                if (bcd_len <= 0 || bcd_len > 11 || bcd_len == 255) next
                num = ""
                if (int(ton_npi / 16) % 8 == 1) {
                  num = "+"
                }
                bcd_bytes = bcd_len - 1
                if (bcd_bytes > 10) bcd_bytes = 10
                for (i = 1; i <= bcd_bytes; i++) {
                  b = hex2val(hex[alpha_len + 2 + i])
                  if (b < 0 || b == 255) break
                  lo = b % 16
                  hi = int(b / 16)
                  d1 = bcd_digit(lo)
                  if (d1 == "") break
                  num = num d1
                  d2 = bcd_digit(hi)
                  if (d2 == "") break
                  num = num d2
                }
                if (num == "" || num == "+") next
                name = ""
                for (i = 1; i <= alpha_len; i++) {
                  b = hex2val(hex[i])
                  if (b < 0 || b == 255) break
                  if (b >= 32 && b < 127 && b != 9) {
                    name = name sprintf("%c", b)
                  }
                }
                gsub(/^[[:space:]]+|[[:space:]]+$/, "", name)
                if (name == "") name = num
                printf "%s\t%s\n", num, name
              }
            ' >> "$tmp_contacts"
          fi
          rec=$((rec + 1))
        done
      fi
    fi

    cat "$tmp_contacts"
    rm -f "$tmp_contacts"
    exit 0
    ;;

  sim-contacts-export)
    req_slot="${2:-auto}"
    src_tsv="${3:-/home/user/.config/sxmo/contacts.tsv}"
    if [ ! -r "$src_tsv" ]; then
      echo "ERROR: Contacts file not found"
      exit 1
    fi
    if ! wait_for_qmicli_modem 3; then
      echo "ERROR: No modem available"
      exit 1
    fi
    QMI_CARDS="$($QMICLI_MODEM --uim-get-card-status 2>/dev/null || true)"
    if [ -z "$QMI_CARDS" ]; then
      echo "ERROR: Cannot read SIM card status"
      exit 1
    fi
    eval "$(parse_uim_card_status "$QMI_CARDS" "$PREFERRED_SIM_SLOT")"

    target_slot=""
    target_aid=""
    if [ "$req_slot" = "1" ]; then
      if [ "$SLOT1_STATE" != "present" ]; then
        echo "ERROR: SIM 1 is not inserted"
        exit 1
      fi
      target_slot="1"
      target_aid="$SLOT1_AID"
    elif [ "$req_slot" = "2" ]; then
      if [ "$SLOT2_STATE" != "present" ]; then
        echo "ERROR: SIM 2 is not inserted"
        exit 1
      fi
      target_slot="2"
      target_aid="$SLOT2_AID"
    else
      if [ "$PRIMARY_GW_SLOT" = "1" ] && [ "$SLOT1_STATE" = "present" ]; then
        target_slot="1"
        target_aid="$SLOT1_AID"
      elif [ "$PRIMARY_GW_SLOT" = "2" ] && [ "$SLOT2_STATE" = "present" ]; then
        target_slot="2"
        target_aid="$SLOT2_AID"
      elif [ "$SLOT1_STATE" = "present" ]; then
        target_slot="1"
        target_aid="$SLOT1_AID"
      elif [ "$SLOT2_STATE" = "present" ]; then
        target_slot="2"
        target_aid="$SLOT2_AID"
      else
        echo "ERROR: No SIM card detected"
        exit 1
      fi
    fi

    orig_gw_slot="$PRIMARY_GW_SLOT"
    orig_gw_aid=""
    if [ "$orig_gw_slot" = "1" ]; then
      orig_gw_aid="$SLOT1_AID"
    elif [ "$orig_gw_slot" = "2" ]; then
      orig_gw_aid="$SLOT2_AID"
    fi
    switched_gw=0
    restore_gw_slot_exp() {
      if [ "$switched_gw" = "1" ]; then
        $QMICLI_MODEM --uim-change-provisioning-session='activate=no,session-type=primary-gw-provisioning' >/dev/null 2>&1 || true
        if [ -n "$orig_gw_slot" ] && [ "$orig_gw_slot" != "0" ] && [ -n "$orig_gw_aid" ]; then
          $QMICLI_MODEM --uim-change-provisioning-session="slot=$orig_gw_slot,activate=yes,session-type=primary-gw-provisioning,aid=$orig_gw_aid" >/dev/null 2>&1 || true
        fi
        switched_gw=0
      fi
    }
    trap restore_gw_slot_exp EXIT INT TERM

    if [ "$PRIMARY_GW_SLOT" != "$target_slot" ] && [ -n "$target_aid" ]; then
      if [ "$PRIMARY_GW_SLOT" != "0" ]; then
        $QMICLI_MODEM --uim-change-provisioning-session='activate=no,session-type=primary-gw-provisioning' >/dev/null 2>&1 || true
      fi
      if $QMICLI_MODEM --uim-change-provisioning-session="slot=$target_slot,activate=yes,session-type=primary-gw-provisioning,aid=$target_aid" >/dev/null 2>&1; then
        switched_gw=1
        sleep 1
      fi
    fi

    at_info="$("$0" at auto 'AT+CMEE=2;+CSCS="GSM";+CPBS="SM";+CPBR=?' 2>/dev/null || true)"
    if printf "%s\n" "$at_info" | grep -qE "ERROR"; then
      echo "ERROR: SIM $target_slot phonebook not ready"
      exit 1
    fi
    tlen="$(printf "%s\n" "$at_info" | sed -n 's/.*+CPBR:[[:space:]]*([0-9]*-[0-9]*),[0-9]*,\([0-9]*\).*/\1/p' | head -n1)"
    if [ -z "$tlen" ] || [ "$tlen" -le 0 ] 2>/dev/null; then
      tlen=14
    fi

    exported=0
    while IFS="$(printf '\t')" read -r raw_num raw_name; do
      num="$(printf "%s" "$raw_num" | tr -cd '+0-9*#')"
      name="$(printf "%s" "$raw_name" | tr -d '"\r\n\t\\' | cut -c1-"$tlen")"
      [ -n "$num" ] || continue
      [ -n "$name" ] || name="$(printf "%s" "$num" | cut -c1-"$tlen")"
      ton=129
      case "$num" in
        +*) ton=145 ;;
      esac
      res="$("$0" at auto "AT+CPBW=,\"${num}\",${ton},\"${name}\"" 2>/dev/null || true)"
      if printf "%s\n" "$res" | grep -q "OK"; then
        exported=$((exported + 1))
      fi
    done < "$src_tsv"

    echo "EXPORTED=${exported}"
    echo "SLOT=${target_slot}"
    exit 0
    ;;

  *)
    echo "Usage: $0 [boot|status|switch <1|2>|verify-pin <slot> <pin>|unblock-puk <slot> <puk> <newpin>|set-pin-lock <slot> <enable|disable> <pin>|change-pin <slot> <oldpin> <newpin>|imei|usb-tether <on|off|status>|at <port> <cmd>|sim-contacts-import [1|2|auto]|sim-contacts-export [1|2|auto] [tsv_file]]" >&2
    exit 1
    ;;
esac