# -*- coding: utf-8 -*-
"""
Log-Formatierer für verschiedene Output-Formate.

Bietet JSON, Text und Compact Formatierung für strukturierte Logs.
"""

from __future__ import annotations

import json
import logging
import traceback
from abc import ABC, abstractmethod
from datetime import datetime
from typing import Any

from trixy_core.utils.logging.context import get_context, get_correlation_id


class BaseFormatter(logging.Formatter, ABC):
    """
    Abstrakte Basisklasse für Log-Formatierer.

    Definiert die gemeinsame Schnittstelle für alle Formatierer
    und bietet Hilfsmethoden für die Verarbeitung von Log-Records.
    """

    # Standard-Zeitformat
    DEFAULT_TIME_FORMAT = "%Y-%m-%dT%H:%M:%S"
    DEFAULT_MSEC_FORMAT = "%s.%03d"

    def __init__(
        self,
        time_format: str | None = None,
        include_context: bool = True,
        include_correlation_id: bool = True,
    ) -> None:
        """
        Initialisiert den Formatierer.

        Args:
            time_format: Optionales Zeitformat (strftime-kompatibel).
            include_context: Ob der Log-Kontext eingefügt werden soll.
            include_correlation_id: Ob die Korrelations-ID eingefügt werden soll.
        """
        super().__init__()
        self.time_format = time_format or self.DEFAULT_TIME_FORMAT
        self.include_context = include_context
        self.include_correlation_id = include_correlation_id

    def format_timestamp(self, record: logging.LogRecord) -> str:
        """
        Formatiert den Zeitstempel eines Log-Records.

        Args:
            record: Der Log-Record.

        Returns:
            Formatierter Zeitstempel als ISO-8601-String.
        """
        ct = datetime.fromtimestamp(record.created)
        return ct.strftime(self.time_format) + f".{int(record.msecs):03d}"

    def format_exception(self, record: logging.LogRecord) -> str | None:
        """
        Formatiert Exception-Informationen.

        Args:
            record: Der Log-Record.

        Returns:
            Formatierter Exception-Traceback oder None.
        """
        if record.exc_info:
            return "".join(traceback.format_exception(*record.exc_info))
        return None

    def get_extra_fields(self, record: logging.LogRecord) -> dict[str, Any]:
        """
        Extrahiert zusätzliche Felder aus dem Log-Record.

        Args:
            record: Der Log-Record.

        Returns:
            Dictionary mit Extra-Feldern.
        """
        # Standard-Attribute, die nicht als Extra gelten
        standard_attrs = {
            "name", "msg", "args", "created", "filename", "funcName",
            "levelname", "levelno", "lineno", "module", "msecs",
            "pathname", "process", "processName", "relativeCreated",
            "stack_info", "exc_info", "exc_text", "thread", "threadName",
            "message", "asctime",
        }

        extra = {}
        for key, value in record.__dict__.items():
            if key not in standard_attrs and not key.startswith("_"):
                extra[key] = value

        return extra

    @abstractmethod
    def format(self, record: logging.LogRecord) -> str:
        """
        Formatiert einen Log-Record.

        Args:
            record: Der zu formatierende Log-Record.

        Returns:
            Formatierter Log-String.
        """
        pass


class JSONFormatter(BaseFormatter):
    """
    JSON-Formatierer für maschinenlesbare Log-Ausgabe.

    Ideal für Log-Aggregation in Systemen wie ELK, Splunk oder CloudWatch.
    """

    def __init__(
        self,
        time_format: str | None = None,
        include_context: bool = True,
        include_correlation_id: bool = True,
        indent: int | None = None,
        ensure_ascii: bool = False,
        include_stacktrace: bool = True,
    ) -> None:
        """
        Initialisiert den JSON-Formatierer.

        Args:
            time_format: Optionales Zeitformat.
            include_context: Ob der Log-Kontext eingefügt werden soll.
            include_correlation_id: Ob die Korrelations-ID eingefügt werden soll.
            indent: Einrückung für Pretty-Print (None für kompakt).
            ensure_ascii: Ob Nicht-ASCII-Zeichen escaped werden sollen.
            include_stacktrace: Ob Stacktraces inkludiert werden sollen.
        """
        super().__init__(time_format, include_context, include_correlation_id)
        self.indent = indent
        self.ensure_ascii = ensure_ascii
        self.include_stacktrace = include_stacktrace

    def format(self, record: logging.LogRecord) -> str:
        """
        Formatiert einen Log-Record als JSON.

        Args:
            record: Der zu formatierende Log-Record.

        Returns:
            JSON-String mit Log-Daten.
        """
        log_data: dict[str, Any] = {
            "timestamp": self.format_timestamp(record),
            "level": record.levelname,
            "logger": record.name,
            "message": record.getMessage(),
        }

        # Korrelations-ID hinzufügen
        if self.include_correlation_id:
            log_data["correlation_id"] = get_correlation_id()

        # Quell-Informationen
        log_data["source"] = {
            "file": record.filename,
            "line": record.lineno,
            "function": record.funcName,
            "module": record.module,
        }

        # Process/Thread-Informationen
        log_data["process"] = {
            "id": record.process,
            "name": record.processName,
        }
        log_data["thread"] = {
            "id": record.thread,
            "name": record.threadName,
        }

        # Kontext hinzufügen
        if self.include_context:
            context = get_context()
            if context:
                log_data["context"] = context

        # Extra-Felder hinzufügen
        extra = self.get_extra_fields(record)
        if extra:
            log_data["extra"] = extra

        # Exception-Informationen
        if self.include_stacktrace:
            exception = self.format_exception(record)
            if exception:
                log_data["exception"] = exception

        return json.dumps(
            log_data,
            indent=self.indent,
            ensure_ascii=self.ensure_ascii,
            default=str,
        )


class TextFormatter(BaseFormatter):
    """
    Klassischer Text-Formatierer für menschenlesbare Log-Ausgabe.

    Enthält optional farbige Ausgabe für Terminal-Nutzung.
    """

    # ANSI-Farbcodes
    COLORS = {
        "DEBUG": "\033[36m",      # Cyan
        "INFO": "\033[32m",       # Grün
        "WARNING": "\033[33m",    # Gelb
        "ERROR": "\033[31m",      # Rot
        "CRITICAL": "\033[35m",   # Magenta
    }
    RESET = "\033[0m"
    BOLD = "\033[1m"
    DIM = "\033[2m"

    def __init__(
        self,
        time_format: str | None = None,
        include_context: bool = True,
        include_correlation_id: bool = True,
        use_colors: bool = True,
        show_source: bool = True,
        format_string: str | None = None,
    ) -> None:
        """
        Initialisiert den Text-Formatierer.

        Args:
            time_format: Optionales Zeitformat.
            include_context: Ob der Log-Kontext eingefügt werden soll.
            include_correlation_id: Ob die Korrelations-ID eingefügt werden soll.
            use_colors: Ob ANSI-Farben verwendet werden sollen.
            show_source: Ob Datei/Zeile angezeigt werden soll.
            format_string: Optionales eigenes Format-Template.
        """
        super().__init__(time_format, include_context, include_correlation_id)
        self.use_colors = use_colors
        self.show_source = show_source
        self.format_string = format_string

    def _colorize(self, text: str, level: str) -> str:
        """Fügt Farbcodes basierend auf dem Log-Level hinzu."""
        if not self.use_colors:
            return text

        color = self.COLORS.get(level, "")
        return f"{color}{text}{self.RESET}"

    def format(self, record: logging.LogRecord) -> str:
        """
        Formatiert einen Log-Record als lesbaren Text.

        Args:
            record: Der zu formatierende Log-Record.

        Returns:
            Formatierter Text-String.
        """
        timestamp = self.format_timestamp(record)
        level = record.levelname.ljust(8)
        message = record.getMessage()

        # Basis-Format
        parts = [
            f"{self.DIM if self.use_colors else ''}{timestamp}{self.RESET if self.use_colors else ''}",
            self._colorize(level, record.levelname),
        ]

        # Korrelations-ID
        if self.include_correlation_id:
            cid = get_correlation_id()[:8]  # Verkürzt für Lesbarkeit
            if self.use_colors:
                parts.append(f"{self.DIM}[{cid}]{self.RESET}")
            else:
                parts.append(f"[{cid}]")

        # Logger-Name
        parts.append(f"[{record.name}]")

        # Nachricht
        parts.append(message)

        # Quell-Information
        if self.show_source:
            source = f"({record.filename}:{record.lineno})"
            if self.use_colors:
                parts.append(f"{self.DIM}{source}{self.RESET}")
            else:
                parts.append(source)

        output = " ".join(parts)

        # Kontext hinzufügen
        if self.include_context:
            context = get_context()
            if context:
                ctx_str = " ".join(f"{k}={v}" for k, v in context.items())
                if self.use_colors:
                    output += f"\n    {self.DIM}Context: {ctx_str}{self.RESET}"
                else:
                    output += f"\n    Context: {ctx_str}"

        # Extra-Felder
        extra = self.get_extra_fields(record)
        if extra:
            extra_str = " ".join(f"{k}={v}" for k, v in extra.items())
            if self.use_colors:
                output += f"\n    {self.DIM}Extra: {extra_str}{self.RESET}"
            else:
                output += f"\n    Extra: {extra_str}"

        # Exception
        exception = self.format_exception(record)
        if exception:
            if self.use_colors:
                output += f"\n{self.COLORS['ERROR']}{exception}{self.RESET}"
            else:
                output += f"\n{exception}"

        return output


class CompactFormatter(BaseFormatter):
    """
    Kompakter Formatierer für minimale Log-Ausgabe.

    Ideal für High-Volume-Logging wo Speicherplatz kritisch ist.
    """

    # Einbuchstabige Level-Codes
    LEVEL_CODES = {
        "DEBUG": "D",
        "INFO": "I",
        "WARNING": "W",
        "ERROR": "E",
        "CRITICAL": "C",
    }

    def __init__(
        self,
        time_format: str | None = None,
        include_context: bool = False,
        include_correlation_id: bool = True,
        separator: str = "|",
    ) -> None:
        """
        Initialisiert den Compact-Formatierer.

        Args:
            time_format: Optionales Zeitformat.
            include_context: Ob der Log-Kontext eingefügt werden soll.
            include_correlation_id: Ob die Korrelations-ID eingefügt werden soll.
            separator: Trennzeichen zwischen Feldern.
        """
        super().__init__(time_format, include_context, include_correlation_id)
        self.separator = separator

    def format(self, record: logging.LogRecord) -> str:
        """
        Formatiert einen Log-Record im Kompakt-Format.

        Args:
            record: Der zu formatierende Log-Record.

        Returns:
            Kompakter Log-String.
        """
        parts = [
            self.format_timestamp(record),
            self.LEVEL_CODES.get(record.levelname, "?"),
        ]

        if self.include_correlation_id:
            parts.append(get_correlation_id()[:8])

        parts.append(record.name)
        parts.append(record.getMessage())

        output = self.separator.join(parts)

        # Exception als zusätzliche Zeile
        exception = self.format_exception(record)
        if exception:
            # Nur erste Zeile des Tracebacks
            first_line = exception.strip().split("\n")[-1]
            output += f"{self.separator}EXC:{first_line}"

        return output


class KeyValueFormatter(BaseFormatter):
    """
    Key-Value-Formatierer für einfache Parsing-Kompatibilität.

    Ausgabe im Format: key1=value1 key2=value2
    """

    def __init__(
        self,
        time_format: str | None = None,
        include_context: bool = True,
        include_correlation_id: bool = True,
        quote_strings: bool = True,
    ) -> None:
        """
        Initialisiert den Key-Value-Formatierer.

        Args:
            time_format: Optionales Zeitformat.
            include_context: Ob der Log-Kontext eingefügt werden soll.
            include_correlation_id: Ob die Korrelations-ID eingefügt werden soll.
            quote_strings: Ob String-Werte in Anführungszeichen gesetzt werden.
        """
        super().__init__(time_format, include_context, include_correlation_id)
        self.quote_strings = quote_strings

    def _format_value(self, value: Any) -> str:
        """Formatiert einen Wert für die Ausgabe."""
        if isinstance(value, str):
            # Escape Anführungszeichen und füge Quotes hinzu
            escaped = value.replace('"', '\\"')
            return f'"{escaped}"' if self.quote_strings else escaped
        return str(value)

    def format(self, record: logging.LogRecord) -> str:
        """
        Formatiert einen Log-Record als Key-Value-Paare.

        Args:
            record: Der zu formatierende Log-Record.

        Returns:
            Key-Value-formatierter String.
        """
        pairs = [
            f"timestamp={self._format_value(self.format_timestamp(record))}",
            f"level={record.levelname}",
            f"logger={record.name}",
            f"message={self._format_value(record.getMessage())}",
        ]

        if self.include_correlation_id:
            pairs.append(f"correlation_id={get_correlation_id()}")

        pairs.extend([
            f"file={record.filename}",
            f"line={record.lineno}",
            f"function={record.funcName}",
        ])

        # Kontext hinzufügen
        if self.include_context:
            context = get_context()
            for key, value in context.items():
                pairs.append(f"ctx_{key}={self._format_value(value)}")

        # Extra-Felder
        extra = self.get_extra_fields(record)
        for key, value in extra.items():
            pairs.append(f"{key}={self._format_value(value)}")

        # Exception
        exception = self.format_exception(record)
        if exception:
            # Nur letzte Zeile (die Exception selbst)
            last_line = exception.strip().split("\n")[-1]
            pairs.append(f"exception={self._format_value(last_line)}")

        return " ".join(pairs)