from __future__ import annotations

from typing import Dict, Iterable, List

from prometheus_client.core import CounterMetricFamily, GaugeMetricFamily, InfoMetricFamily

from .models import DeviceHealthState, DeviceMetricsSnapshot


class TransceiverCollector:
    """
    自定义 Collector，基于 MetricsCache 与 HealthState 输出所有指标。
    """

    def __init__(
        self,
        cache: Dict[str, DeviceMetricsSnapshot],
        health: Dict[str, DeviceHealthState],
    ) -> None:
        self._cache = cache
        self._health = health

    def collect(self) -> Iterable:
        # 复制快照，避免长时间持锁（由调用方负责线程安全）
        cache_items = list(self._cache.items())
        health_items = list(self._health.items())

        # 健康指标
        scrape_duration = GaugeMetricFamily(
            "netconf_scrape_duration_seconds",
            "Duration of last NETCONF scrape per device",
            labels=["device"],
        )
        scrape_success = GaugeMetricFamily(
            "netconf_scrape_success",
            "Whether last NETCONF scrape succeeded (1) or failed (0)",
            labels=["device"],
        )
        last_scrape_ts = GaugeMetricFamily(
            "netconf_last_scrape_timestamp_seconds",
            "Timestamp of last NETCONF scrape per device",
            labels=["device"],
        )
        staleness = GaugeMetricFamily(
            "transceiver_data_staleness_seconds",
            "Age of last successful transceiver scrape per device",
            labels=["device"],
        )
        errors_total = CounterMetricFamily(
            "netconf_scrape_errors_total",
            "Total number of NETCONF scrape errors by device and type",
            labels=["device", "error_type"],
        )

        # health map for quick lookup
        health_map = dict(health_items)

        # 填充健康指标
        for device, hs in health_items:
            if hs.last_scrape_duration is not None:
                scrape_duration.add_metric([device], hs.last_scrape_duration)
            if hs.last_scrape_success is not None:
                scrape_success.add_metric([device], 1.0 if hs.last_scrape_success else 0.0)
            if hs.last_scrape_timestamp is not None:
                last_scrape_ts.add_metric([device], hs.last_scrape_timestamp)
            if hs.last_error_type:
                errors_total.add_metric([device, hs.last_error_type], 1.0)

        # 业务指标
        tx_temp = GaugeMetricFamily(
            "transceiver_temperature_celsius",
            "Transceiver temperature in degrees Celsius",
            labels=["device", "port", "component_name"],
        )
        tx_supply_v = GaugeMetricFamily(
            "transceiver_supply_voltage_volts",
            "Transceiver supply voltage",
            labels=["device", "port", "component_name"],
        )
        tx_present = GaugeMetricFamily(
            "transceiver_present",
            "Transceiver present state (1 present, 0 otherwise)",
            labels=["device", "port", "component_name"],
        )

        ch_rx_power = GaugeMetricFamily(
            "transceiver_channel_rx_power_dbm",
            "Receive optical power per channel (dBm)",
            labels=["device", "port", "channel", "component_name"],
        )
        ch_tx_power = GaugeMetricFamily(
            "transceiver_channel_tx_power_dbm",
            "Transmit optical power per channel (dBm)",
            labels=["device", "port", "channel", "component_name"],
        )
        ch_bias = GaugeMetricFamily(
            "transceiver_channel_bias_current_ma",
            "Laser bias current per channel (mA)",
            labels=["device", "port", "channel", "component_name"],
        )
        ch_laser_temp = GaugeMetricFamily(
            "transceiver_channel_laser_temperature_celsius",
            "Laser temperature per channel (Celsius)",
            labels=["device", "port", "channel", "component_name"],
        )

        tx_info = InfoMetricFamily(
            "transceiver_info",
            "Transceiver static information",
            labels=["device", "port", "component_name", "vendor", "serial", "form_factor", "part_number", "hardware_rev"],
        )
        ch_info = InfoMetricFamily(
            "transceiver_channel_info",
            "Transceiver channel info",
            labels=["device", "port", "channel", "channel_index", "component_name"],
        )

        # 为 last_scrape_success==True 的设备导出业务指标
        for device, snapshot in cache_items:
            hs = health_map.get(device)
            if not hs or not hs.last_scrape_success:
                continue

            # transceiver 指标
            for t in snapshot.transceivers:
                labels = [t.device, t.logical_port, t.component_name]
                if t.temperature_c is not None:
                    tx_temp.add_metric(labels, t.temperature_c)
                if t.supply_voltage_v is not None:
                    tx_supply_v.add_metric(labels, t.supply_voltage_v)
                if t.present is not None:
                    present_val = 1.0 if t.present.upper() == "PRESENT" else 0.0
                    tx_present.add_metric(labels, present_val)

                # Info
                info_labels = [
                    t.device,
                    t.logical_port,
                    t.component_name,
                    t.vendor or "",
                    t.serial or "",
                    "",  # form_factor 留空占位
                    t.part_number or "",
                    t.hardware_rev or "",
                ]
                tx_info.add_metric(info_labels, {})

            # channel 指标
            for ch in snapshot.channels:
                labels = [ch.device, ch.logical_port, ch.logical_channel, ch.component_name]
                if ch.rx_power_dbm is not None:
                    ch_rx_power.add_metric(labels, ch.rx_power_dbm)
                if ch.tx_power_dbm is not None:
                    ch_tx_power.add_metric(labels, ch.tx_power_dbm)
                if ch.bias_current_ma is not None:
                    ch_bias.add_metric(labels, ch.bias_current_ma)
                if ch.laser_temperature_c is not None:
                    ch_laser_temp.add_metric(labels, ch.laser_temperature_c)

                ch_info.add_metric(
                    [
                        ch.device,
                        ch.logical_port,
                        ch.logical_channel,
                        str(ch.channel_index),
                        ch.component_name,
                    ],
                    {},
                )

        # 依次 yield 所有指标
        yield scrape_duration
        yield scrape_success
        yield last_scrape_ts
        yield staleness
        yield errors_total

        yield tx_temp
        yield tx_supply_v
        yield tx_present
        yield ch_rx_power
        yield ch_tx_power
        yield ch_bias
        yield ch_laser_temp
        yield tx_info
        yield ch_info