#!/bin/bash
# Script d'analyse hebdomadaire des éléments obsolètes sur le système
# Génère un rapport et l'envoie par email à admin@keller-laurent.org

set -euo pipefail

REPORT=$(mktemp)
trap 'rm -f "$REPORT"' EXIT

{
echo "═══════════════════════════════════════════════"
echo "  RAPPORT HEBDOMADAIRE — ÉLÉMENTS OBSOLÈTES"
echo "  $(date '+%Y-%m-%d %H:%M') — $(hostname)"
echo "═══════════════════════════════════════════════"
echo ""

# ── 1. Paquets orphelins (autoremove) ──
echo "── 1. PAQUETS ORPHELINS (autoremove) ──────────"
orphans=$(apt-get --just-print autoremove 2>&1 | grep "Remv" | sed 's/Remv //' | sed 's/ \[.*//' || true)
orphan_count=$(echo "$orphans" | grep -c . || true)
if [ "$orphan_count" -eq 0 ]; then
    echo "  Aucun paquet orphelin."
else
    orphan_size=$(dpkg-query -Wf '${Package}\t${Installed-Size}\n' $orphans 2>/dev/null | awk '{sum+=$2} END {printf "%.0f", sum/1024}')
    echo "  Paquets: $orphan_count  |  Taille: ${orphan_size:-0} MB"
    echo ""
    echo "  Top 10 plus gros :"
    dpkg-query -Wf '${Package}\t${Installed-Size}\n' $orphans 2>/dev/null | sort -t$'\t' -k2 -rn | head -10 | awk '{printf "    %-40s %d MB\n", $1, $2/1024}'
fi
echo ""

# ── 2. Anciens noyaux ──
echo "── 2. ANCIENS NOYAUX ──────────────────────────"
current_kernel=$(uname -r)
installed_kernels=$(dpkg -l 'linux-image-*' 2>/dev/null | grep '^ii' | awk '{print $2}' | sort -V || true)
old_kernels=$(echo "$installed_kernels" | grep -v "$(echo $current_kernel | sed 's/-[^-]*$//')" || true)
old_count=$(echo "$old_kernels" | grep -c . || true)
echo "  Noyau actif : $current_kernel"
if [ "$old_count" -eq 0 ]; then
    echo "  Aucun ancien noyau."
else
    echo "  Anciens noyaux installés : $old_count"
    echo "$old_kernels" | sed 's/^/    /'
fi
echo ""

# ── 3. Cache APT ──
echo "── 3. CACHE APT ───────────────────────────────"
apt_cache=$(du -sh /var/cache/apt/archives/ 2>/dev/null | awk '{print $1}')
echo "  Taille : $apt_cache"
echo ""

# ── 4. Journaux systemd ──
echo "── 4. JOURNAUX SYSTEMD ────────────────────────"
journal_size=$(journalctl --disk-usage 2>&1 | grep -oP '[\d.]+[GMK]' || echo "?")
echo "  Taille : $journal_size"
echo ""

# ── 5. Conteneurs/images Docker inutilisés ──
if command -v docker &>/dev/null; then
    echo "── 5. DOCKER ──────────────────────────────────"
    unused_containers=$(docker container ls -a --filter status=exited --filter status=created -q 2>/dev/null | wc -l)
    dangling_images=$(docker images -f dangling=true -q 2>/dev/null | wc -l)
    unused_volumes=$(docker volume ls -f dangling=true -q 2>/dev/null | wc -l)
    echo "  Conteneurs arrêtés : $unused_containers"
    echo "  Images dangling : $dangling_images"
    echo "  Volumes orphelins : $unused_volumes"
    echo ""
fi

# ── 6. Espace disque ──
echo "── 6. ESPACE DISQUE ───────────────────────────"
df -h / | tail -1 | awk '{printf "  Utilisé: %s / %s  (%s libre)\n", $3, $2, $4}'
echo ""

# ── 7. Fichiers temporaires volumineux ──
echo "── 7. FICHIERS TEMPORAIRES VOLUMINEUX ─────────"
tmp_size=$(du -sh /tmp 2>/dev/null | awk '{print $1}')
echo "  /tmp : $tmp_size"
echo ""

echo "═══════════════════════════════════════════════"
echo "  FIN DU RAPPORT"
echo "═══════════════════════════════════════════════"
} > "$REPORT"

# Output for cron delivery
cat "$REPORT"