#!/bin/bash
# ═══════════════════════════════════════════════════════════════════════════════
# monitor_postgres_tables.sh — Surveillance tailles tables ADS-B PostgreSQL
# Version : 2.0 — JCA 2026
# Usage   : ./monitor_postgres_tables.sh [--alert THRESHOLD_MB] [--init]
#   --alert N  : alerte si positions ou aircraft_history dépasse N Mo (défaut 5000)
#   --init     : crée la table adsb.table_size_history si elle n'existe pas
# ═══════════════════════════════════════════════════════════════════════════════

# ── Configuration ─────────────────────────────────────────────────────────────
PG_USER="pgz_admin"
PG_DB="wpz_postgres"
PG_SCHEMA="adsb"
ALERT_THRESHOLD_MB=5000

# ── Couleurs ──────────────────────────────────────────────────────────────────
GREEN='\033[0;32m'; RED='\033[0;31m'; YELLOW='\033[1;33m'
CYAN='\033[0;36m'; BLUE='\033[1;34m'; BOLD='\033[1m'; NC='\033[0m'

ok()   { echo -e "  ${GREEN}✓${NC} $1"; }
fail() { echo -e "  ${RED}✗${NC} $1"; }
warn() { echo -e "  ${YELLOW}⚠${NC} $1"; }
info() { echo -e "  ${CYAN}→${NC} $1"; }
hdr()  { echo -e "\n${BLUE}${BOLD}── $1 ──${NC}"; }

# ── Parsing des arguments ─────────────────────────────────────────────────────
DO_INIT=false
while [[ $# -gt 0 ]]; do
    case "$1" in
        --alert)  ALERT_THRESHOLD_MB="$2"; shift 2 ;;
        --init)   DO_INIT=true; shift ;;
        *) echo "Usage: $0 [--alert THRESHOLD_MB] [--init]"; exit 1 ;;
    esac
done

# ── Helper psql ───────────────────────────────────────────────────────────────
pg() { docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -t -c "$1" 2>/dev/null | xargs; }

# ── Vérification Docker ───────────────────────────────────────────────────────
if ! docker inspect wordpress-postgres &>/dev/null; then
    fail "Conteneur wordpress-postgres inaccessible"
    exit 1
fi

# ── Init : création de la table d'historique ──────────────────────────────────
if [ "$DO_INIT" = true ]; then
    echo -e "${BOLD}Création de adsb.table_size_history...${NC}"
    TMP_INIT=$(mktemp /tmp/pg_init_XXXXXX.sql)
    trap "rm -f $TMP_INIT" EXIT
    cat > "$TMP_INIT" << 'ENDINIT'
CREATE TABLE IF NOT EXISTS adsb.table_size_history (
    id              SERIAL PRIMARY KEY,
    captured_at     TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    table_name      VARCHAR(60)  NOT NULL,
    total_bytes     BIGINT       NOT NULL,
    table_bytes     BIGINT       NOT NULL,
    index_bytes     BIGINT       NOT NULL,
    row_estimate    BIGINT       NOT NULL,
    partition_count INTEGER      NOT NULL DEFAULT 0
);
CREATE INDEX IF NOT EXISTS tsh_captured_at_idx ON adsb.table_size_history (captured_at DESC);
CREATE INDEX IF NOT EXISTS tsh_table_name_idx  ON adsb.table_size_history (table_name, captured_at DESC);
COMMENT ON TABLE adsb.table_size_history IS 'Historique tailles tables ADS-B — monitor_postgres_tables.sh';
ENDINIT
    docker cp "$TMP_INIT" wordpress-postgres:/tmp/pg_init.sql 2>/dev/null
    docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -f /tmp/pg_init.sql 2>&1
    RET=$?
    docker exec wordpress-postgres rm -f /tmp/pg_init.sql 2>/dev/null
    rm -f "$TMP_INIT"
    if [ $RET -eq 0 ]; then
        ok "Table adsb.table_size_history créée (ou déjà existante)"
    else
        fail "Erreur lors de la création de la table"
        exit 1
    fi
    echo ""
fi

# ── En-tête ───────────────────────────────────────────────────────────────────
NOW=$(date '+%Y-%m-%d %H:%M:%S')
echo -e "${BOLD}╔══════════════════════════════════════════════════════╗${NC}"
echo -e "${BOLD}║   Surveillance tailles tables ADS-B PostgreSQL       ║${NC}"
echo -e "${BOLD}║   $NOW                              ║${NC}"
echo -e "${BOLD}╚══════════════════════════════════════════════════════╝${NC}"

# ── Collecte des métriques via une seule requête ──────────────────────────────
hdr "Collecte des métriques"

# Écrire la requête dans un fichier temporaire (heredoc dans $() est instable en bash)
TMP_SQL=$(mktemp /tmp/pg_monitor_XXXXXX.sql)
trap "rm -f $TMP_SQL" EXIT

cat > "$TMP_SQL" << 'ENDSQL'
WITH parent_tables AS (
    SELECT
        pt.relname                                                  AS table_name,
        pg_total_relation_size(pt.oid)                             AS total_bytes,
        pg_relation_size(pt.oid)                                   AS table_bytes,
        pg_indexes_size(pt.oid)                                    AS index_bytes,
        COALESCE((
            SELECT SUM(child.reltuples::BIGINT)
            FROM pg_inherits inh
            JOIN pg_class child  ON child.oid  = inh.inhrelid
            JOIN pg_class parent ON parent.oid = inh.inhparent
            WHERE parent.relname      = pt.relname
              AND parent.relnamespace = pt.relnamespace
        ), pt.reltuples::BIGINT)                                   AS row_estimate,
        (SELECT COUNT(*) FROM pg_inherits WHERE inhparent = pt.oid) AS partition_count
    FROM pg_class     pt
    JOIN pg_namespace ns ON ns.oid = pt.relnamespace
    WHERE ns.nspname = 'adsb'
      AND pt.relkind IN ('r','p')
      AND pt.relname IN ('positions', 'aircraft_history', 'receivers')
),
aggregated AS (
    SELECT
        pt.table_name,
        CASE WHEN pt.partition_count > 0 THEN COALESCE((
            SELECT SUM(pg_total_relation_size(child.oid))
            FROM pg_inherits inh
            JOIN pg_class child  ON child.oid  = inh.inhrelid
            JOIN pg_class parent ON parent.oid = inh.inhparent
            WHERE parent.relname = pt.table_name
              AND parent.relnamespace = (SELECT oid FROM pg_namespace WHERE nspname='adsb')
        ), 0) ELSE pt.total_bytes END                              AS total_bytes,
        CASE WHEN pt.partition_count > 0 THEN COALESCE((
            SELECT SUM(pg_relation_size(child.oid))
            FROM pg_inherits inh
            JOIN pg_class child  ON child.oid  = inh.inhrelid
            JOIN pg_class parent ON parent.oid = inh.inhparent
            WHERE parent.relname = pt.table_name
              AND parent.relnamespace = (SELECT oid FROM pg_namespace WHERE nspname='adsb')
        ), 0) ELSE pt.table_bytes END                              AS table_bytes,
        CASE WHEN pt.partition_count > 0 THEN COALESCE((
            SELECT SUM(pg_indexes_size(child.oid))
            FROM pg_inherits inh
            JOIN pg_class child  ON child.oid  = inh.inhrelid
            JOIN pg_class parent ON parent.oid = inh.inhparent
            WHERE parent.relname = pt.table_name
              AND parent.relnamespace = (SELECT oid FROM pg_namespace WHERE nspname='adsb')
        ), 0) ELSE pt.index_bytes END                              AS index_bytes,
        pt.row_estimate,
        pt.partition_count
    FROM parent_tables pt
)
SELECT
    table_name,
    total_bytes,
    table_bytes,
    index_bytes,
    row_estimate,
    partition_count,
    pg_size_pretty(total_bytes)              AS total_pretty,
    pg_size_pretty(table_bytes)              AS data_pretty,
    pg_size_pretty(index_bytes)              AS idx_pretty,
    ROUND(total_bytes / 1024.0 / 1024.0, 1) AS total_mb
FROM aggregated
ORDER BY total_bytes DESC;
ENDSQL

# Copier le fichier SQL dans le conteneur et exécuter
docker cp "$TMP_SQL" wordpress-postgres:/tmp/pg_monitor.sql 2>/dev/null
METRICS=$(docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -t -f /tmp/pg_monitor.sql 2>&1)
docker exec wordpress-postgres rm -f /tmp/pg_monitor.sql 2>/dev/null

if [ -z "$METRICS" ]; then
    fail "Impossible de collecter les métriques PostgreSQL"
    exit 1
fi
ok "Métriques collectées"

# ── Affichage et insertion ────────────────────────────────────────────────────
hdr "Tailles actuelles"

ALERT_MSGS=()

while IFS='|' read -r table_name total_bytes table_bytes index_bytes row_estimate partition_count total_pretty data_pretty idx_pretty total_mb; do
    # Nettoyer les espaces
    table_name=$(echo "$table_name"      | xargs)
    total_bytes=$(echo "$total_bytes"    | xargs)
    table_bytes=$(echo "$table_bytes"    | xargs)
    index_bytes=$(echo "$index_bytes"    | xargs)
    row_estimate=$(echo "$row_estimate"  | xargs)
    partition_count=$(echo "$partition_count" | xargs)
    total_pretty=$(echo "$total_pretty"  | xargs)
    data_pretty=$(echo "$data_pretty"    | xargs)
    idx_pretty=$(echo "$idx_pretty"      | xargs)
    total_mb=$(echo "$total_mb"          | xargs)

    [ -z "$table_name" ] && continue

    # Récupérer la mesure précédente
    PREV=$(docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -t -c "
        SELECT total_bytes, captured_at::TEXT
        FROM adsb.table_size_history
        WHERE table_name = '$table_name'
        ORDER BY captured_at DESC
        LIMIT 1;" 2>/dev/null | xargs)

    PREV_BYTES=$(echo "$PREV" | awk '{print $1}')
    PREV_DATE=$(echo "$PREV"  | awk '{print $2, $3}')

    # Calculer la croissance
    GROWTH_STR=""
    if [ -n "$PREV_BYTES" ] && [ "$PREV_BYTES" -gt 0 ] 2>/dev/null; then
        GROWTH_BYTES=$(( total_bytes - PREV_BYTES ))
        GROWTH_MB=$(awk "BEGIN{printf \"%.1f\", $GROWTH_BYTES/1024/1024}")
        GROWTH_PCT=$(awk "BEGIN{printf \"%.2f\", ($GROWTH_BYTES/$PREV_BYTES)*100}")
        if [ "$GROWTH_BYTES" -gt 0 ]; then
            GROWTH_STR=" ${GREEN}(+${GROWTH_MB} MB / +${GROWTH_PCT}% depuis $PREV_DATE)${NC}"
        elif [ "$GROWTH_BYTES" -lt 0 ]; then
            ABS_MB=$(awk "BEGIN{printf \"%.1f\", -$GROWTH_BYTES/1024/1024}")
            GROWTH_STR=" ${YELLOW}(-${ABS_MB} MB depuis $PREV_DATE)${NC}"
        else
            GROWTH_STR=" ${CYAN}(stable depuis $PREV_DATE)${NC}"
        fi
    fi

    # Affichage
    echo -e "  ${BOLD}${table_name}${NC}"
    echo -e "    Total     : ${BOLD}${total_pretty}${NC}${GROWTH_STR}"
    echo -e "    Données   : ${data_pretty}  |  Index : ${idx_pretty}"
    echo -e "    Lignes    : ~$(printf "%'d" "${row_estimate:-0}" 2>/dev/null || echo "$row_estimate")  |  Partitions : ${partition_count}"
    echo ""

    # Alerte seuil
    TOTAL_MB_INT=$(echo "$total_mb" | cut -d. -f1)
    if [ "${TOTAL_MB_INT:-0}" -gt "$ALERT_THRESHOLD_MB" ] 2>/dev/null; then
        ALERT_MSGS+=("$table_name : ${total_pretty} dépasse le seuil de ${ALERT_THRESHOLD_MB} MB")
    fi

    # Insertion dans l'historique
    INSERT_RESULT=$(docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -t -c "
        INSERT INTO adsb.table_size_history
            (table_name, total_bytes, table_bytes, index_bytes, row_estimate, partition_count)
        VALUES
            ('$table_name', $total_bytes, $table_bytes, $index_bytes,
             ${row_estimate:-0}, ${partition_count:-0})
        RETURNING id;" 2>/dev/null | xargs)

    if [ -n "$INSERT_RESULT" ]; then
        info "Enregistrement #${INSERT_RESULT} inséré dans adsb.table_size_history"
    else
        warn "Impossible d'insérer dans adsb.table_size_history (table créée ? Lancer avec --init)"
    fi

done <<< "$METRICS"

# ── Évolution sur 7 jours ─────────────────────────────────────────────────────
hdr "Évolution sur 7 jours"

docker exec wordpress-postgres psql -U "$PG_USER" -d "$PG_DB" -c "
SELECT
    table_name                                          AS \"Table\",
    TO_CHAR(captured_at, 'YYYY-MM-DD HH24:MI')         AS \"Horodatage\",
    pg_size_pretty(total_bytes)                         AS \"Total\",
    pg_size_pretty(total_bytes
        - LAG(total_bytes) OVER (PARTITION BY table_name ORDER BY captured_at))
                                                        AS \"Delta\",
    partition_count                                     AS \"Parts\",
    TO_CHAR(row_estimate, 'FM999,999,999,999')          AS \"Lignes estimées\"
FROM adsb.table_size_history
WHERE captured_at >= NOW() - INTERVAL '7 days'
  AND table_name IN ('positions','aircraft_history')
ORDER BY table_name, captured_at DESC
LIMIT 30;" 2>/dev/null || warn "Table adsb.table_size_history absente — lancer avec --init"

# ── Alertes ───────────────────────────────────────────────────────────────────
if [ ${#ALERT_MSGS[@]} -gt 0 ]; then
    echo ""
    echo -e "${RED}${BOLD}═══ ALERTES ═══${NC}"
    for msg in "${ALERT_MSGS[@]}"; do
        echo -e "  ${RED}⚠ $msg${NC}"
    done
fi

# ── Résumé ────────────────────────────────────────────────────────────────────
echo ""
echo -e "${BOLD}╔══════════════════════════════════════════════════════╗${NC}"
echo -e "${BOLD}║  Historique : SELECT * FROM adsb.table_size_history  ║${NC}"
echo -e "${BOLD}║  Seuil alerte : ${ALERT_THRESHOLD_MB} MB                              ║${NC}"
echo -e "${BOLD}╚══════════════════════════════════════════════════════╝${NC}"