"""
Data models for the metrics module.
"""
from datetime import datetime, timedelta, timezone
from typing import List, Dict, Any, Optional
from dataclasses import dataclass

# Default time range: last 1 hour
DEFAULT_END_TIME = datetime.now(timezone.utc)
DEFAULT_START_TIME = DEFAULT_END_TIME - timedelta(hours=1)

# Default metrics to query
DEFAULT_METRICS = [
    "tidb_server_query_total",
    "tidb_server_connections",
    "tidb_server_handle_query_duration_seconds",
    "process_cpu_seconds_total",
    "process_resident_memory_bytes"
]


@dataclass
class MetricDataPoint:
    """A single data point for a metric."""
    timestamp: float
    value: float
    labels: Dict[str, str]


@dataclass
class MetricsQuery:
    """Parameters for querying metrics."""
    cluster_id: str
    start_time: datetime
    end_time: datetime
    metrics: List[str]
    instance: Optional[str] = None
    step: str = "15s"


@dataclass
class MetricsResult:
    """Result of a metrics query."""
    status: str
    data: Dict[str, Any]
    error: Optional[str] = None
    warnings: Optional[List[str]] = None


# Type aliases for better type hints
MetricName = str
InstanceName = str
MetricValues = Dict[float, float]  # timestamp -> value
MetricSeries = Dict[InstanceName, MetricValues]