import json
from typing import Optional

from prometheus_client import Counter, Histogram

WEBHOOK_EVENTS_TOTAL = Counter(
    "matrix_ops_bot_webhook_events_total",
    "Incoming webhook events by source and processing result.",
    ["source", "result"],
)

MESSAGES_SENT_TOTAL = Counter(
    "matrix_ops_bot_messages_sent_total",
    "Messages successfully sent to Matrix by source.",
    ["source"],
)

MESSAGE_SEND_FAILURES_TOTAL = Counter(
    "matrix_ops_bot_message_send_failures_total",
    "Failures while sending messages to Matrix by source and reason.",
    ["source", "reason"],
)

MATRIX_AUTH_TOTAL = Counter(
    "matrix_ops_bot_matrix_auth_total",
    "Matrix authentication and credential-restore attempts by mode and result.",
    ["mode", "result"],
)

MATRIX_SYNC_ERRORS_TOTAL = Counter(
    "matrix_ops_bot_matrix_sync_errors_total",
    "Matrix sync loop errors by coarse reason.",
    ["reason"],
)

EVENT_TO_SEND_SECONDS = Histogram(
    "matrix_ops_bot_event_to_send_seconds",
    "Time from webhook receipt to first Matrix send attempt by source.",
    ["source"],
)

CONFIG_LOADED_TOTAL = Counter(
    "matrix_ops_bot_config_loaded_total",
    "Bot config load outcomes at startup.",
    ["result"],
)


def source_label(source: Optional[str]) -> str:
    if source is None:
        return "unknown"
    normalized = source.strip().lower().replace("-", "_")
    if normalized in {"gitlab", "pagerduty", "aws_sns", "alertmanager"}:
        return normalized
    return "unknown"


def classify_send_failure(exc: Exception) -> str:
    msg = f"{type(exc).__name__} {exc}".lower()
    if "forbidden" in msg or "403" in msg:
        return "forbidden"
    if "rate limit" in msg or "too many requests" in msg or "429" in msg:
        return "ratelimit"
    if "unknown room" in msg or "room not found" in msg:
        return "unknown_room"
    if (
        "timeout" in msg
        or "connection" in msg
        or "network" in msg
        or "dns" in msg
        or "refused" in msg
    ):
        return "network"
    return "exception"


def classify_sync_error(exc: Exception) -> str:
    msg = f"{type(exc).__name__} {exc}".lower()
    if "401" in msg or "403" in msg or "unauthorized" in msg or "forbidden" in msg:
        return "auth"
    if (
        "timeout" in msg
        or "connection" in msg
        or "network" in msg
        or "dns" in msg
        or "refused" in msg
    ):
        return "network"
    if "megolm" in msg or "olm" in msg or "decrypt" in msg:
        return "crypto"
    return "unknown"


def classify_payload_error(exc: Exception) -> str:
    if isinstance(exc, (ValueError, TypeError, KeyError, json.JSONDecodeError)):
        return "invalid_payload"
    return "handler_error"