#!/bin/sh
# gentoo_snapshot.sh - collect a system snapshot on Gentoo/OpenRC systems
# Usage: gentoo_snapshot.sh [output_file]
# Default output file is gentoo_snapshot.txt in the current directory.

set -e

OUTPUT=${1:-gentoo_snapshot.txt}
TMPDIR=$(mktemp -d)

cleanup() {
    rm -rf "$TMPDIR"
}
trap cleanup EXIT

printf "===== Gentoo System Snapshot: %s =====\n" "$(date)" > "$OUTPUT"

printf "\n## Kernel\n" >> "$OUTPUT"
uname -a >> "$OUTPUT" 2>/dev/null || printf "uname not available\n" >> "$OUTPUT"

printf "\n## CPU\n" >> "$OUTPUT"
(lscpu 2>/dev/null || printf "lscpu not available\n") >> "$OUTPUT"

printf "\n## Memory\n" >> "$OUTPUT"
(free -h 2>/dev/null || printf "free not available\n") >> "$OUTPUT"

printf "\n## Block Devices\n" >> "$OUTPUT"
(lsblk 2>/dev/null || printf "lsblk not available\n") >> "$OUTPUT"

printf "\n## Storage Usage\n" >> "$OUTPUT"
(df -h 2>/dev/null || printf "df not available\n") >> "$OUTPUT"

# Installed packages
printf "\n## Installed Packages\n" >> "$OUTPUT"
if command -v qlist >/dev/null 2>&1; then
    qlist -I >> "$OUTPUT"
elif command -v equery >/dev/null 2>&1; then
    equery list '*' >> "$OUTPUT"
else
    printf "Package manager tools (qlist/equery) not found\n" >> "$OUTPUT"
fi

# OpenRC services
printf "\n## OpenRC Services\n" >> "$OUTPUT"
if command -v rc-update >/dev/null 2>&1; then
    printf "\n### Enabled\n" >> "$OUTPUT"
    rc-update show | awk '{print $1}' | sort -u >> "$OUTPUT"

    printf "\n### Disabled\n" >> "$OUTPUT"
    ENAB="$TMPDIR/enabled"
    ALL="$TMPDIR/all"
    rc-update show | awk '{print $1}' | sort -u > "$ENAB"
    ls /etc/init.d 2>/dev/null | sort > "$ALL" || true
    if [ -s "$ALL" ]; then
        comm -23 "$ALL" "$ENAB" >> "$OUTPUT" || true
    else
        printf "/etc/init.d not accessible\n" >> "$OUTPUT"
    fi
else
    printf "rc-update not found\n" >> "$OUTPUT"
fi

# Largest files
printf "\n## Largest Files\n" >> "$OUTPUT"
(find / -xdev -type f -printf '%s\t%p\n' 2>/dev/null | sort -nr | head -n 20 2>/dev/null || printf "find not available\n") >> "$OUTPUT"

# Cleanup suggestions
printf "\n## Cleanup Suggestions\n" >> "$OUTPUT"
if [ -d /var/cache/distfiles ]; then
    du -sh /var/cache/distfiles 2>/dev/null | awk '{print "Distfiles cache: "$1}' >> "$OUTPUT"
fi
if [ -d /var/tmp/portage ]; then
    du -sh /var/tmp/portage 2>/dev/null | awk '{print "Portage build dir: "$1}' >> "$OUTPUT"
fi
printf "Consider running 'eclean packages' and 'eclean distfiles'\n" >> "$OUTPUT"

# Additional information
printf "\n## Environment\n" >> "$OUTPUT"
(printenv 2>/dev/null || printf "printenv not available\n") >> "$OUTPUT"

printf "\nSnapshot saved to %s\n" "$OUTPUT" >> "$OUTPUT"