#!/bin/bash
set -u

PACKAGE_ROOT=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
APP_ROOT="${TRIM_APPDEST:-$PACKAGE_ROOT/app}"
DATA_ROOT="${TRIM_PKGVAR:-$PACKAGE_ROOT/var}"
VOLUME_ROOT="${TRIM_APPDEST_VOL:-$DATA_ROOT/volume}"
BACKUP_ROOT="${POSTGRES_SERVICE_BACKUP_ROOT:-$VOLUME_ROOT/@appshare/postgresql/backups}"
RUNTIME_ROOT="$APP_ROOT/runtime"
SERVER="$APP_ROOT/server/PostgresService.WebApi"
PG_BIN="$RUNTIME_ROOT/usr/lib/postgresql/15/bin"
PG_SHARE="$RUNTIME_ROOT/usr/share/postgresql/15"
PG_LIB="$RUNTIME_ROOT/usr/lib/postgresql/15/lib"
PG_DATA="$DATA_ROOT/postgres"
RUN_ROOT="$DATA_ROOT/run"
LOG_ROOT="$DATA_ROOT/log"
APP_PID_FILE="$RUN_ROOT/postgres-service.pid"
APP_LOG="$LOG_ROOT/postgres-service.log"
PG_LOG="$LOG_ROOT/postgresql.log"
PG_PORT="${POSTGRES_SERVICE_PORT:-15432}"
SERVICE_PORT="${TRIM_SERVICE_PORT:-15433}"
RUNTIME_PATH="$PG_BIN:$RUNTIME_ROOT/usr/bin:${PATH:-/usr/local/bin:/usr/bin:/bin}"
RUNTIME_LIBRARY_PATH="$RUNTIME_ROOT/usr/lib/x86_64-linux-gnu:$RUNTIME_ROOT/lib/x86_64-linux-gnu:$PG_LIB"

log_message() {
    mkdir -p "$LOG_ROOT"
    printf '%s - %s\n' "$(date '+%Y-%m-%d %H:%M:%S')" "$1" >>"$APP_LOG"
}

run_pg() {
    env LD_LIBRARY_PATH="$RUNTIME_LIBRARY_PATH" PATH="$RUNTIME_PATH" "$@"
}

app_pid() {
    if [ -f "$APP_PID_FILE" ]; then
        pid=$(sed -n '1p' "$APP_PID_FILE" | tr -d '[:space:]')
        if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
            printf '%s' "$pid"
            return 0
        fi
    fi
    return 1
}

postgres_running() {
    [ -x "$PG_BIN/pg_ctl" ] || return 1
    [ -f "$PG_DATA/PG_VERSION" ] || return 1
    run_pg "$PG_BIN/pg_ctl" -D "$PG_DATA" status >/dev/null 2>&1
}

initialize_postgres() {
    [ ! -f "$PG_DATA/PG_VERSION" ] || return 0
    mkdir -p "$PG_DATA" "$RUN_ROOT" "$LOG_ROOT"
    chmod 0700 "$PG_DATA" "$RUN_ROOT"
    run_pg "$PG_BIN/initdb" \
        -D "$PG_DATA" \
        -L "$PG_SHARE" \
        --username=postgres_service \
        --auth-local=trust \
        --auth-host=scram-sha-256 \
        --encoding=UTF8 \
        --no-locale >>"$PG_LOG" 2>&1 || return 1

    {
        printf "listen_addresses = '127.0.0.1'\n"
        printf "port = %s\n" "$PG_PORT"
        printf "unix_socket_directories = '%s'\n" "$RUN_ROOT"
        printf "password_encryption = 'scram-sha-256'\n"
        printf "max_connections = 100\n"
        printf "shared_buffers = '128MB'\n"
        printf "timezone = 'UTC'\n"
        printf "log_timezone = 'UTC'\n"
        printf "log_min_duration_statement = 5000\n"
    } >>"$PG_DATA/postgresql.conf"

    {
        printf 'local all postgres_service trust\n'
        printf 'local all all reject\n'
        printf 'host all all 127.0.0.1/32 scram-sha-256\n'
        printf 'host all all ::1/128 scram-sha-256\n'
    } >"$PG_DATA/pg_hba.conf"
}

start_postgres() {
    postgres_running && return 0
    initialize_postgres || { log_message "PostgreSQL 初始化失败。"; return 1; }
    run_pg "$PG_BIN/pg_ctl" -D "$PG_DATA" -l "$PG_LOG" -w start || {
        log_message "PostgreSQL 启动失败。"
        return 1
    }
}

stop_postgres() {
    if postgres_running; then
        run_pg "$PG_BIN/pg_ctl" -D "$PG_DATA" -m fast -t 180 -w stop >>"$PG_LOG" 2>&1 || {
            log_message "PostgreSQL 未能在 180 秒内安全停止。"
            return 1
        }
    fi
}

start_app() {
    mkdir -p "$DATA_ROOT" "$RUN_ROOT" "$LOG_ROOT" "$BACKUP_ROOT" "$DATA_ROOT/tmp" "$DATA_ROOT/cache"
    chmod 0700 "$DATA_ROOT" "$RUN_ROOT" "$DATA_ROOT/tmp" "$DATA_ROOT/cache" 2>/dev/null || true
    [ -x "$SERVER" ] || { log_message "管理服务不存在或不可执行：$SERVER"; return 1; }
    [ -x "$PG_BIN/postgres" ] || { log_message "PostgreSQL 原生运行环境不完整。"; return 1; }
    if app_pid >/dev/null; then return 0; fi
    start_postgres || return 1

    (
        export ASPNETCORE_ENVIRONMENT=Production
        export ASPNETCORE_URLS="http://0.0.0.0:$SERVICE_PORT"
        export POSTGRES_SERVICE_DATA_ROOT="$DATA_ROOT"
        export POSTGRES_SERVICE_SOCKET_ROOT="$RUN_ROOT"
        export POSTGRES_SERVICE_PORT="$PG_PORT"
        export POSTGRES_SERVICE_ADMIN_USER=postgres_service
        export POSTGRES_SERVICE_PG_BIN="$PG_BIN"
        export POSTGRES_SERVICE_BACKUP_ROOT="$BACKUP_ROOT"
        export DOTNET_SYSTEM_GLOBALIZATION_INVARIANT=1
        export DOTNET_BUNDLE_EXTRACT_BASE_DIR="$DATA_ROOT/dotnet-bundle"
        export XDG_CACHE_HOME="$DATA_ROOT/cache"
        export TMPDIR="$DATA_ROOT/tmp"
        export LD_LIBRARY_PATH="$RUNTIME_LIBRARY_PATH"
        export PATH="$RUNTIME_PATH"
        mkdir -p "$DOTNET_BUNDLE_EXTRACT_BASE_DIR"
        cd "$APP_ROOT/server" || exit 1
        exec "$SERVER"
    ) >>"$APP_LOG" 2>&1 &
    pid=$!
    printf '%s\n' "$pid" >"$APP_PID_FILE"

    attempt=0
    while [ "$attempt" -lt 90 ]; do
        if ! kill -0 "$pid" 2>/dev/null; then
            log_message "管理服务进程提前退出。"
            stop_postgres
            return 1
        fi
        if (exec 3<>"/dev/tcp/127.0.0.1/$SERVICE_PORT") 2>/dev/null; then
            exec 3>&-
            log_message "PostgreSQL 共享服务启动成功，管理端口 $SERVICE_PORT，数据库端口 $PG_PORT。"
            return 0
        fi
        attempt=$((attempt + 1))
        sleep 1
    done
    log_message "管理服务未能在 90 秒内就绪。"
    stop_app
    return 1
}

stop_app() {
    if pid=$(app_pid); then
        kill "$pid" 2>/dev/null || true
        attempt=0
        while kill -0 "$pid" 2>/dev/null && [ "$attempt" -lt 30 ]; do
            sleep 1
            attempt=$((attempt + 1))
        done
        kill -9 "$pid" 2>/dev/null || true
    fi
    rm -f "$APP_PID_FILE"
    stop_postgres
}

case "${1:-status}" in
    start) start_app ;;
    stop) stop_app ;;
    restart) stop_app && start_app ;;
    status)
        if app_pid >/dev/null && postgres_running; then exit 0; fi
        exit 3
        ;;
    *) printf 'usage: %s {start|stop|restart|status}\n' "$0" >&2; exit 2 ;;
esac