#!/bin/bash

# 2020-10-27: Most of the 11 variables require a command[*] to be run to
# establish the var's value.  WE DISPLAY ALL ERRORS / DIAGNOSTICS AND CONTINUE.
#
# [*] DOESN'T MATTER WHAT COMMAND: so long as it fails with Return Code != 0
# If statements then use that RC to force the var to these default values...

STAGE=0
OS="none"
VERSION_ID="none"    # This var's combined with the above, before being output
IIAB_BRANCH="none"
IIAB_COMMIT="none"
XO_MODEL="none"
RPI_MODEL="none"
ANSIBLE_VERSION="none"
DHCPCD="none"    # The last 3 conditioned on string output not RC.  SEE BELOW.
NETWORK_MANAGER="none"
SYSTEMD_NETWORKD="none"


# STAGE variable is for ./iiab-install which runs Ansible with iiab-stages.yml
# - fresh installs start at STAGE 0
# - interrupted installs record the last completed STAGE (1-9)
#
# We initialize it to '0' (zero) to cover the following 2 possibs: (1) iiab.env
# doesn't exist, or (2) iiab.env exists but fails to set STAGE=<something>
source /etc/iiab/iiab.env || true    # STAGE var auto-set, so no "if" required.

# /etc/lsb-release could also be grep'd.  But /etc/upstream-release/lsb-release
# on Linux Mint 20 caused grep of /etc/*elease to fail (on directory not file)
if tmp=$(grep ^ID= /etc/os-release); then
    OS=$(echo "$tmp" | cut -d= -f2)
    OS=${OS//\"/}    # Remove all '"'
fi
if [ -f /etc/rpi-issue ]; then
    OS="raspbian"    # For 64-bit Raspberry Pi OS which contains "ID=debian" as
fi    # of 2020: https://github.com/raspberrypi/Raspberry-Pi-OS-64bit/issues/6

if tmp=$(grep ^VERSION_ID= /etc/os-release); then
    VERSION_ID=$(echo "$tmp" | cut -d= -f2)
    VERSION_ID=${VERSION_ID//\"/}   # Remove all '"'
    VERSION_ID=${VERSION_ID%%.*}    # Remove all '.' & stuff to the right of em
fi
OS_VER=$OS-$VERSION_ID

# Previously supported Linux distributions / versions:
    #"fedora-18"    | \
    #"fedora-22"    | \
    #"debian-8"     | \
    #"debian-9"     | \
    #"ubuntu-16"    | \
    #"ubuntu-17"    | \
    #"ubuntu-18"    | \
    #"ubuntu-19"    | \
    #"centos-7"     | \
    #"raspbian-8"   | \
    #"raspbian-9"   | \

# 2020-10-21: Debian 11 (Bullseye) not yet supported but adding this line to
# its /etc/os-release can help testing this unreleased OS: VERSION_ID="11"

# 2020-11-14: Ubuntu 21.04 (Hirsute Hippo) not yet supported but this
# unreleased OS can help testing.

case $OS_VER in
    "debian-10"    | \
    "debian-11"    | \
    "ubuntu-20"    | \
    "ubuntu-21"    | \
    "linuxmint-20" | \
    "raspbian-10")
       ;;
    *) OS_VER="OS_not_supported"
       ;;
esac

# These next 2 help indicate what version of IIAB
tmp=$(git rev-parse --abbrev-ref HEAD) &&
    IIAB_BRANCH=$tmp

tmp=$(git rev-parse --verify HEAD) &&
    IIAB_COMMIT=$tmp

tmp=$(cat /proc/device-tree/mfg-data/MN) &&
    XO_MODEL=$tmp

tmp=$(cat /proc/device-tree/model) &&
    RPI_MODEL=$tmp

tmp=$(ansible --version) &&
    ANSIBLE_VERSION=$(echo "$tmp" | head -n 1 | cut -f 2 -d " ")


# THE LAST 3 BELOW ARE DIFFERENT as "systemctl is-enabled" unhelpfully returns
# the same error code (i.e. 1) REGARDLESS whether the service is (A) disabled
# or (B) doesn't exist. SO WE TEST THE STRING OUTPUT INSTEAD OF THE RETURN CODE

tmp=$(systemctl is-enabled dhcpcd)
[[ $tmp != "" ]] &&
    DHCPCD=$tmp
#[[ $tmp ]] && DHCPCD=$tmp    # Short Ain't Sweet (less understandable)

# is_redhat uses "NetworkManager".  Debian 7 & Ubuntu 14.10 required
# "network-manager" (prior to 2015/systemd).  Ubuntu 20.10 dropped the
# legacy symlink from "network-manager.service" to "NetworkManager.service"
tmp=$(systemctl is-enabled NetworkManager)
[[ $tmp != "" ]] &&
    NETWORK_MANAGER=$tmp

tmp=$(systemctl is-enabled systemd-networkd)
[[ $tmp != "" ]] &&
    SYSTEMD_NETWORKD=$tmp


cat <<EOF
{"stage"                  : "$STAGE",
"dhcpcd"                  : "$DHCPCD",
"network_manager"         : "$NETWORK_MANAGER",
"systemd_networkd"        : "$SYSTEMD_NETWORKD",
"iiab_branch"             : "$IIAB_BRANCH",
"iiab_commit"             : "$IIAB_COMMIT",
"xo_model"                : "$XO_MODEL",
"rpi_model"               : "$RPI_MODEL",
"ansible_version"         : "$ANSIBLE_VERSION",
"os"                      : "$OS",
"os_ver"                  : "$OS_VER"}
EOF
