"""
Saxon Worker Pool (s9api) - Persistente JVM-Prozesse für XSLT 2.0/3.0 Transformationen.

Diese Variante verwendet die Saxon s9api API anstatt JAXP und ist für XSLT 2.0 und 3.0 geeignet.
Eliminiert JVM-Startup-Overhead durch Vorinitialisierung von N Worker-Prozessen.
Jeder Worker läuft als Daemon und verarbeitet mehrere Transformationen nacheinander.
"""

import logging
import subprocess
import threading
import time
import psutil
from pathlib import Path
from queue import Queue
from typing import Optional
import tempfile

from worker_metrics import WorkerPoolMetrics

logger = logging.getLogger(__name__)

# Java-Worker-Code für s9api (wird zur Laufzeit kompiliert)
SAXON_S9API_WORKER_JAVA = """
import net.sf.saxon.s9api.*;
import javax.xml.transform.stream.StreamSource;
import java.io.*;
import java.util.HashMap;
import java.util.Map;

public class SaxonS9ApiWorker {
    public static void main(String[] args) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String line;

        // Create Processor once and reuse (equivalent to TransformerFactory)
        Processor processor = new Processor(false);

        // Cache für kompilierte Stylesheets (Performance-Optimierung)
        Map<String, XsltExecutable> stylesheetCache = new HashMap<>();

        System.err.println("SaxonS9ApiWorker started and ready (using s9api for XSLT 2.0/3.0 with stylesheet caching)");
        System.err.flush();

        try {
            while ((line = reader.readLine()) != null) {
                System.err.println("DEBUG: Received line: " + line.substring(0, Math.min(100, line.length())));
                System.err.flush();

                if ("EXIT".equals(line.trim())) {
                    System.err.println("SaxonS9ApiWorker exiting");
                    break;
                }

                try {
                    // Parse job
                    System.err.println("DEBUG: Parsing job...");
                    System.err.flush();

                    String[] parts = line.split("\\\\t");
                    System.err.println("DEBUG: Parts count: " + parts.length);
                    System.err.flush();

                    if (parts.length < 3) {
                        System.out.println("ERROR: Invalid job format");
                        System.out.flush();
                        continue;
                    }

                    String sourceXml = parts[0];
                    String xslStylesheet = parts[1];
                    String outputFo = parts[2];

                    // Prüfe ob Stylesheet bereits im Cache ist
                    XsltExecutable executable;
                    if (stylesheetCache.containsKey(xslStylesheet)) {
                        executable = stylesheetCache.get(xslStylesheet);
                        System.err.println("DEBUG: Using cached stylesheet: " + xslStylesheet);
                        System.err.flush();
                    } else {
                        System.err.println("DEBUG: Compiling and caching stylesheet: " + xslStylesheet);
                        System.err.flush();

                        XsltCompiler compiler = processor.newXsltCompiler();
                        executable = compiler.compile(new StreamSource(new File(xslStylesheet)));
                        stylesheetCache.put(xslStylesheet, executable);

                        System.err.println("DEBUG: Stylesheet compiled and cached (cache size: " + stylesheetCache.size() + ")");
                        System.err.flush();
                    }

                    System.err.println("DEBUG: Creating transformer...");
                    System.err.flush();

                    // Create transformer
                    XsltTransformer transformer = executable.load();

                    // Set source
                    transformer.setSource(new StreamSource(new File(sourceXml)));

                    // Set destination
                    Serializer serializer = processor.newSerializer(new File(outputFo));
                    transformer.setDestination(serializer);

                    // Set parameters if present
                    if (parts.length > 3 && !parts[3].isEmpty()) {
                        String[] params = parts[3].split("\\\\|\\\\|\\\\|");
                        for (String param : params) {
                            if (!param.isEmpty() && param.contains("=")) {
                                String[] kv = param.split("=", 2);
                                transformer.setParameter(new QName(kv[0]), new XdmAtomicValue(kv[1]));
                                System.err.println("DEBUG: Set parameter: " + kv[0] + " = " + kv[1]);
                            }
                        }
                        System.err.flush();
                    }

                    System.err.println("DEBUG: Running transformation...");
                    System.err.flush();

                    // Transform
                    transformer.transform();

                    System.err.println("DEBUG: Transformation completed");
                    System.err.flush();

                    System.out.println("OK");
                    System.out.flush();

                } catch (SaxonApiException e) {
                    System.err.println("DEBUG: SaxonApiException: " + e.getClass().getName());
                    System.err.flush();
                    e.printStackTrace(System.err);

                    String errorMsg = e.getMessage();
                    if (errorMsg == null || errorMsg.isEmpty()) {
                        errorMsg = e.getClass().getSimpleName();
                    }
                    System.out.println("ERROR: " + errorMsg);
                    System.out.flush();

                } catch (Exception e) {
                    System.err.println("DEBUG: Job processing exception: " + e.getClass().getName());
                    System.err.flush();
                    e.printStackTrace(System.err);
                    System.out.println("ERROR: " + (e.getMessage() != null ? e.getMessage() : e.getClass().getName()));
                    System.out.flush();
                }
            }
        } catch (IOException e) {
            System.err.println("SaxonS9ApiWorker I/O error: " + e.getMessage());
            e.printStackTrace(System.err);
        }
    }
}
"""


class SaxonWorkerPoolS9Api:
    """
    Pool von lang-laufenden JVM-Prozessen für Saxon-Transformationen mit s9api.

    Diese Variante verwendet die Saxon s9api API anstatt JAXP und unterstützt
    vollständig XSLT 2.0 und 3.0 Transformationen.
    """

    def __init__(
        self,
        num_workers: int,
        java_vm_path: Path,
        saxon_jar_path: Path,
        classpath_cache: dict[Path, str],
        log_dir: Optional[Path] = None,
    ):
        """
        Initialisiert den Saxon-Worker-Pool mit s9api.

        Args:
            num_workers: Anzahl der Worker-Prozesse
            java_vm_path: Pfad zur Java VM Binary
            saxon_jar_path: Pfad zur Saxon JAR-Datei
            classpath_cache: Cache für Saxon-Classpaths
            log_dir: Optionales Verzeichnis für Worker-Logs (Standard: temp_dir/tmp)
        """
        self.num_workers = num_workers
        self.java_vm_path = java_vm_path
        self.saxon_jar_path = saxon_jar_path
        self.classpath_cache = classpath_cache
        self.log_dir = log_dir

        # Worker-Prozesse und Queues
        self.workers: list[subprocess.Popen] = []
        self.job_queue: Queue = Queue()
        self.result_queue: Queue = Queue()
        self.worker_locks: list[threading.Lock] = []

        # Temporäres Verzeichnis für kompilierte Java-Klasse
        self.temp_dir: Optional[Path] = None
        self.worker_class_path: Optional[Path] = None
        self.worker_log_dir: Optional[Path] = None

        # Performance-Metriken
        self.metrics = WorkerPoolMetrics()

        # Initialisierung
        self._compile_worker_class()
        self._start_workers()

        logger.info(f"SaxonWorkerPoolS9Api initialisiert mit {num_workers} Workern (XSLT 2.0/3.0)")

    def _compile_worker_class(self):
        """Kompiliert die SaxonS9ApiWorker-Java-Klasse."""
        start_time = time.time()
        try:
            # Erstelle temporäres Verzeichnis
            self.temp_dir = Path(tempfile.mkdtemp(prefix="saxon_s9api_worker_"))

            # Schreibe Java-Quellcode
            java_file = self.temp_dir / "SaxonS9ApiWorker.java"
            java_file.write_text(SAXON_S9API_WORKER_JAVA, encoding="utf-8")

            # Hole Classpath
            saxon_dir = self.saxon_jar_path.parent
            if saxon_dir in self.classpath_cache:
                classpath = self.classpath_cache[saxon_dir]
            else:
                # Fallback: Baue Classpath neu
                import glob
                import sys

                all_jars = glob.glob(str(saxon_dir / "*.jar"))
                lib_dir = saxon_dir / "lib"
                if lib_dir.exists():
                    all_jars.extend(glob.glob(str(lib_dir / "*.jar")))

                classpath_separator = ";" if sys.platform == "win32" else ":"
                classpath = classpath_separator.join(all_jars)

            # Kompiliere Java-Klasse
            javac_cmd = [str(self.java_vm_path).replace("java", "javac"), "-cp", classpath, str(java_file)]

            logger.debug(f"Kompiliere SaxonS9ApiWorker: {' '.join(javac_cmd)}")

            result = subprocess.run(javac_cmd, capture_output=True, text=True, timeout=30)

            if result.returncode != 0:
                raise RuntimeError(f"Java-Kompilierung fehlgeschlagen: {result.stderr}")

            self.worker_class_path = self.temp_dir

            # Speichere Kompilierungszeit
            self.metrics.compilation_time_seconds = time.time() - start_time

            logger.info(
                f"SaxonS9ApiWorker erfolgreich kompiliert: {self.temp_dir} "
                f"({self.metrics.compilation_time_seconds:.3f}s)"
            )

        except Exception as e:
            logger.error(f"Fehler beim Kompilieren von SaxonS9ApiWorker: {e}")
            raise

    def _start_workers(self):
        """Startet N Worker-Prozesse."""
        # Hole Classpath
        saxon_dir = self.saxon_jar_path.parent
        if saxon_dir in self.classpath_cache:
            classpath = self.classpath_cache[saxon_dir]
        else:
            # Fallback: Baue Classpath neu (sollte nicht nötig sein, aber zur Sicherheit)
            import glob
            import sys

            all_jars = glob.glob(str(saxon_dir / "*.jar"))
            lib_dir = saxon_dir / "lib"
            if lib_dir.exists():
                all_jars.extend(glob.glob(str(lib_dir / "*.jar")))

            classpath_separator = ";" if sys.platform == "win32" else ":"
            classpath = classpath_separator.join(all_jars)

            # Cache für zukünftige Verwendung
            self.classpath_cache[saxon_dir] = classpath
            logger.debug(f"Classpath für {saxon_dir} neu erstellt und gecacht")

        # Füge Worker-Classpath hinzu
        import sys

        classpath_separator = ";" if sys.platform == "win32" else ":"
        full_classpath = str(self.worker_class_path) + classpath_separator + classpath

        logger.debug(f"S9Api Worker Classpath: {full_classpath[:200]}...")

        # Bestimme Log-Verzeichnis
        self.worker_log_dir = self.log_dir if self.log_dir else self.temp_dir
        if self.log_dir:
            self.worker_log_dir.mkdir(parents=True, exist_ok=True)

        for i in range(self.num_workers):
            worker_start_time = time.time()
            try:
                # Starte JVM-Prozess mit SaxonS9ApiWorker
                cmd = [str(self.java_vm_path), "-cp", full_classpath, "SaxonS9ApiWorker"]

                # Öffne stderr-Log-Datei für diesen Worker
                stderr_log = self.worker_log_dir / f"s9api_worker_{i}_stderr.log"
                stderr_file = open(stderr_log, "w", encoding="utf-8")

                process = subprocess.Popen(
                    cmd,
                    stdin=subprocess.PIPE,
                    stdout=subprocess.PIPE,
                    stderr=stderr_file,  # Redirect stderr to file
                    text=True,
                    bufsize=1,  # Line buffered
                )

                self.workers.append(process)
                self.worker_locks.append(threading.Lock())

                logger.debug(f"S9Api Worker {i} gestartet (PID: {process.pid}, stderr: {stderr_log})")

                # Warte kurz damit Worker initialisieren kann
                time.sleep(0.1)

                # Prüfe ob Worker noch läuft
                if process.poll() is not None:
                    # Worker ist bereits beendet - Fehler!
                    stderr_file.close()
                    with open(stderr_log, "r") as f:
                        stderr_content = f.read()
                    raise RuntimeError(
                        f"S9Api Worker {i} ist sofort beendet (Exit Code: {process.returncode})\nstderr:\n{stderr_content}"
                    )

                # Speichere Worker-Startzeit
                worker_elapsed = time.time() - worker_start_time
                self.metrics.worker_start_times.append(worker_elapsed)

            except Exception as e:
                logger.error(f"Fehler beim Starten von S9Api Worker {i}: {e}")
                raise

        # Berechne Aggregat-Werte für Worker-Startzeiten
        self.metrics.calculate_aggregates()

        logger.info(
            f"{len(self.workers)} Saxon-S9Api-Worker erfolgreich gestartet "
            f"(Summe: {self.metrics.total_worker_start_time_seconds:.3f}s, "
            f"Durchschnitt: {self.metrics.average_worker_start_time_seconds:.3f}s)"
        )

    def transform(
        self, source_xml: Path, xsl_stylesheet: Path, output_fo: Path, xslt_params: dict[str, str]
    ) -> tuple[bool, str]:
        """
        Führt eine XSLT-Transformation mit einem Worker aus dem Pool aus.

        Args:
            source_xml: Pfad zur XML-Eingabedatei
            xsl_stylesheet: Pfad zur XSL-Stylesheet-Datei
            output_fo: Pfad zur FO-Ausgabedatei
            xslt_params: Dictionary mit XSLT-Parametern

        Returns:
            tuple[bool, str]: (Erfolg, Fehlermeldung/Info)
        """
        # Finde freien Worker
        worker_idx = None
        for i, lock in enumerate(self.worker_locks):
            if lock.acquire(blocking=False):
                worker_idx = i
                break

        if worker_idx is None:
            # Kein freier Worker, warte auf ersten verfügbaren
            for i, lock in enumerate(self.worker_locks):
                lock.acquire()
                worker_idx = i
                break

        try:
            worker = self.workers[worker_idx]

            # Prüfe ob Worker noch läuft
            if worker.poll() is not None:
                # Worker ist tot!
                stderr_log = self.worker_log_dir / f"s9api_worker_{worker_idx}_stderr.log"
                try:
                    with open(stderr_log, "r") as f:
                        stderr_content = f.read()
                    error_msg = (
                        f"S9Api Worker {worker_idx} ist beendet (Exit: {worker.returncode})\nstderr:\n{stderr_content}"
                    )
                except Exception:
                    error_msg = f"S9Api Worker {worker_idx} ist beendet (Exit: {worker.returncode})"
                logger.error(error_msg)
                return False, error_msg

            # Formatiere Parameter
            params_str = "|||".join([f"{key}={value}" for key, value in xslt_params.items()])

            # Erstelle Job-String (Tab-separated)
            job = f"{source_xml}\t{xsl_stylesheet}\t{output_fo}\t{params_str}\n"

            logger.debug(f"Sende Job an S9Api Worker {worker_idx}: {source_xml.name}")

            # Sende Job an Worker
            worker.stdin.write(job)
            worker.stdin.flush()

            # Warte auf Antwort
            response = worker.stdout.readline().strip()

            logger.debug(f"S9Api Worker {worker_idx} Antwort: '{response}'")

            if response == "OK":
                return True, "Erfolgreich"
            elif response.startswith("ERROR:"):
                error_msg = response[6:].strip()
                return False, f"Saxon-Fehler (s9api): {error_msg}"
            else:
                # Leere Antwort bedeutet Worker ist crashed
                if not response:
                    stderr_log = self.worker_log_dir / f"s9api_worker_{worker_idx}_stderr.log"
                    try:
                        with open(stderr_log, "r") as f:
                            stderr_content = f.read()[-500:]  # Letzte 500 Zeichen
                        return False, f"S9Api Worker {worker_idx} crashed (keine Antwort)\nstderr:\n{stderr_content}"
                    except Exception:
                        return False, f"S9Api Worker {worker_idx} crashed (keine Antwort)"
                return False, f"Unerwartete Antwort: {response}"

        except Exception as e:
            logger.error(f"Fehler bei S9Api Worker {worker_idx}: {e}")
            return False, f"Worker-Fehler: {str(e)}"

        finally:
            # Gebe Worker-Lock frei
            self.worker_locks[worker_idx].release()

    def measure_ram_usage(self) -> tuple[float, float, list[float]]:
        """
        Misst den aktuellen RAM-Verbrauch aller Worker-Prozesse.

        Returns:
            tuple: (total_mb, average_mb, per_worker_mb_list)
        """
        ram_per_worker = []

        for i, worker in enumerate(self.workers):
            try:
                if worker.poll() is None:  # Worker läuft noch
                    process = psutil.Process(worker.pid)
                    # Hole Speicherinfo (RSS = Resident Set Size in Bytes)
                    mem_info = process.memory_info()
                    ram_mb = mem_info.rss / (1024 * 1024)  # Konvertiere zu MB
                    ram_per_worker.append(ram_mb)
                else:
                    logger.warning(f"Worker {i} ist nicht mehr aktiv (kann RAM nicht messen)")
            except (psutil.NoSuchProcess, psutil.AccessDenied) as e:
                logger.warning(f"Konnte RAM für Worker {i} nicht messen: {e}")

        total_ram = sum(ram_per_worker)
        average_ram = total_ram / len(ram_per_worker) if ram_per_worker else 0.0

        return total_ram, average_ram, ram_per_worker

    def capture_ram_before_transform(self):
        """Erfasst RAM-Verbrauch vor der ersten Transformation."""
        total, average, per_worker = self.measure_ram_usage()
        self.metrics.ram_before_transform_mb_per_worker = per_worker
        self.metrics.total_ram_before_mb = total
        self.metrics.average_ram_before_mb = average

        logger.info(
            f"RAM vor Transformation: {self.metrics.total_ram_before_mb:.1f} MB "
            f"(Durchschnitt: {self.metrics.average_ram_before_mb:.1f} MB/Worker)"
        )

    def capture_ram_after_transform(self):
        """Erfasst RAM-Verbrauch nach allen Transformationen."""
        total, average, per_worker = self.measure_ram_usage()
        self.metrics.ram_after_transform_mb_per_worker = per_worker
        self.metrics.total_ram_after_mb = total
        self.metrics.average_ram_after_mb = average

        logger.info(
            f"RAM nach Transformation: {self.metrics.total_ram_after_mb:.1f} MB "
            f"(Durchschnitt: {self.metrics.average_ram_after_mb:.1f} MB/Worker)"
        )

    def shutdown(self):
        """Beendet alle Worker-Prozesse sauber."""
        logger.info("Beende Saxon-S9Api-Worker-Pool...")

        for i, worker in enumerate(self.workers):
            try:
                # Sende EXIT-Befehl
                if worker.stdin and not worker.stdin.closed:
                    worker.stdin.write("EXIT\n")
                    worker.stdin.flush()

                # Warte auf Beendigung (max 2 Sekunden)
                worker.wait(timeout=2)
                logger.debug(f"S9Api Worker {i} beendet")

            except subprocess.TimeoutExpired:
                # Force kill falls nötig
                worker.kill()
                logger.warning(f"S9Api Worker {i} musste gekillt werden")

            except Exception as e:
                logger.error(f"Fehler beim Beenden von S9Api Worker {i}: {e}")

        # Lösche temporäres Verzeichnis
        if self.temp_dir and self.temp_dir.exists():
            try:
                import shutil

                shutil.rmtree(self.temp_dir)
                logger.debug(f"Temporäres Verzeichnis gelöscht: {self.temp_dir}")
            except Exception as e:
                logger.warning(f"Konnte temporäres Verzeichnis nicht löschen: {e}")

        logger.info("Saxon-S9Api-Worker-Pool beendet")

    def __enter__(self):
        """Context manager entry."""
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        """Context manager exit."""
        self.shutdown()