#!/bin/bash
set -x

# ==========================================================
# VERIFY BACKUP INTEGRITY
# Kontroluje že se všechny DB, tabulky a data
# správně obnovily po restore
# ==========================================================

CONTAINER_NAME="postgresql18"
PG_HOST="localhost"
PG_PORT="5432"
PG_USER="vladimir.buzalka"
export PGPASSWORD="Vlado7309208104++"

echo "Starting PostgreSQL backup integrity verification..."
echo "=========================================="

ALL_OK=true

# ==========================================================
# 1. CONNECTIVITY CHECK
# ==========================================================
echo ""
echo "Checking PostgreSQL connectivity..."
docker exec \
    -e PGPASSWORD="$PGPASSWORD" \
    "$CONTAINER_NAME" \
    psql \
        --host="$PG_HOST" \
        --port="$PG_PORT" \
        --username="$PG_USER" \
        --dbname="postgres" \
        --tuples-only \
        --command="SELECT 'connected';" > /dev/null 2>&1

if [ $? -ne 0 ]; then
    echo "ERROR: Cannot connect to PostgreSQL!"
    exit 1
fi
echo "OK: Connected to PostgreSQL"

# ==========================================================
# 2. LIST ALL DATABASES
# ==========================================================
echo ""
echo "Databases present:"
docker exec \
    -e PGPASSWORD="$PGPASSWORD" \
    "$CONTAINER_NAME" \
    psql \
        --host="$PG_HOST" \
        --port="$PG_PORT" \
        --username="$PG_USER" \
        --dbname="postgres" \
        --tuples-only \
        --command="SELECT datname FROM pg_database WHERE datistemplate = false ORDER BY datname;"

# Ulož seznam DB do proměnné pro iteraci
DATABASES=$(docker exec \
    -e PGPASSWORD="$PGPASSWORD" \
    "$CONTAINER_NAME" \
    psql \
        --host="$PG_HOST" \
        --port="$PG_PORT" \
        --username="$PG_USER" \
        --dbname="postgres" \
        --tuples-only \
        --command="SELECT datname FROM pg_database WHERE datistemplate = false ORDER BY datname;" \
    | tr -d ' ')

# ==========================================================
# 3. PER-DATABASE CHECKS
# ==========================================================
for DB_NAME in $DATABASES; do
    [ -z "$DB_NAME" ] && continue

    echo ""
    echo "Verifying database: $DB_NAME"
    echo "------------------------------------------"

    # Počet tabulek
    TABLE_COUNT=$(docker exec \
        -e PGPASSWORD="$PGPASSWORD" \
        "$CONTAINER_NAME" \
        psql \
            --host="$PG_HOST" \
            --port="$PG_PORT" \
            --username="$PG_USER" \
            --dbname="$DB_NAME" \
            --tuples-only \
            --command="SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'public';" \
        | tr -d ' ')

    echo "OK: Tables in public schema: $TABLE_COUNT"

    # Seznam tabulek s počtem řádků
    echo "   Table row counts:"
    docker exec \
        -e PGPASSWORD="$PGPASSWORD" \
        "$CONTAINER_NAME" \
        psql \
            --host="$PG_HOST" \
            --port="$PG_PORT" \
            --username="$PG_USER" \
            --dbname="$DB_NAME" \
            --tuples-only \
            --command="
SELECT
    schemaname || '.' || relname AS table_name,
    n_live_tup AS estimated_rows,
    pg_size_pretty(pg_total_relation_size(relid)) AS total_size
FROM pg_stat_user_tables
ORDER BY relname;"

    # Počet indexů
    INDEX_COUNT=$(docker exec \
        -e PGPASSWORD="$PGPASSWORD" \
        "$CONTAINER_NAME" \
        psql \
            --host="$PG_HOST" \
            --port="$PG_PORT" \
            --username="$PG_USER" \
            --dbname="$DB_NAME" \
            --tuples-only \
            --command="SELECT COUNT(*) FROM pg_indexes WHERE schemaname = 'public';" \
        | tr -d ' ')

    echo "OK: Indexes in public schema: $INDEX_COUNT"

    # Celková velikost DB
    DB_SIZE=$(docker exec \
        -e PGPASSWORD="$PGPASSWORD" \
        "$CONTAINER_NAME" \
        psql \
            --host="$PG_HOST" \
            --port="$PG_PORT" \
            --username="$PG_USER" \
            --dbname="$DB_NAME" \
            --tuples-only \
            --command="SELECT pg_size_pretty(pg_database_size('$DB_NAME'));" \
        | tr -d ' ')

    echo "OK: Database size: $DB_SIZE"

done

# ==========================================================
# 4. CHECK ROLES / USERS
# ==========================================================
echo ""
echo "PostgreSQL roles:"
docker exec \
    -e PGPASSWORD="$PGPASSWORD" \
    "$CONTAINER_NAME" \
    psql \
        --host="$PG_HOST" \
        --port="$PG_PORT" \
        --username="$PG_USER" \
        --dbname="postgres" \
        --command="SELECT rolname, rolsuper, rolcreatedb, rolcanlogin FROM pg_roles WHERE rolname NOT LIKE 'pg_%' ORDER BY rolname;"

echo ""
echo "=========================================="
if [ "$ALL_OK" = true ]; then
    echo "OK: All verifications passed!"
else
    echo "ERROR: Some verifications failed!"
    exit 1
fi
set +x