"""
sfm/server.py — Seismograph Field Module REST API

Wraps the minimateplus library in a small FastAPI service.
Terra-view proxies /api/sfm/* to this service (same pattern as SLMM at :8100).

Default port: 8200

Endpoints
---------
GET  /health              Service heartbeat — no device I/O
GET  /device/info         POLL + serial number + full config read
GET  /device/events       Download all stored events (headers + peak values)
POST /device/connect      Explicit connect/identify (same as /device/info)
GET  /device/event/{idx}  Single event by index (header + waveform record)

Transport query params (supply one set):
  Serial (direct RS-232 cable):
    port  — serial port name (e.g. COM5, /dev/ttyUSB0)
    baud  — baud rate (default 38400)

  TCP (modem / ACH Auto Call Home):
    host      — IP address or hostname of the modem or ACH relay
    tcp_port  — TCP port number (default 12345, Blastware default)

Each call opens the connection, does its work, then closes it.
(Stateless / reconnect-per-call, matching Blastware's observed behaviour.)

Run with:
    python -m uvicorn sfm.server:app --host 0.0.0.0 --port 8200 --reload
or:
    python sfm/server.py
"""

from __future__ import annotations

import logging
import sys
from typing import Optional

# FastAPI / Pydantic
try:
    from fastapi import FastAPI, HTTPException, Query
    from fastapi.responses import JSONResponse
    import uvicorn
except ImportError:
    print(
        "fastapi and uvicorn are required for the SFM server.\n"
        "Install them with:  pip install fastapi uvicorn",
        file=sys.stderr,
    )
    sys.exit(1)

from minimateplus import MiniMateClient
from minimateplus.protocol import ProtocolError
from minimateplus.models import DeviceInfo, Event, PeakValues, ProjectInfo, Timestamp
from minimateplus.transport import TcpTransport, DEFAULT_TCP_PORT

logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s  %(levelname)-7s  %(name)s  %(message)s",
    datefmt="%H:%M:%S",
)
log = logging.getLogger("sfm.server")

# ── FastAPI app ────────────────────────────────────────────────────────────────

app = FastAPI(
    title="Seismograph Field Module (SFM)",
    description=(
        "REST API for Instantel MiniMate Plus seismographs.\n"
        "Implements the minimateplus RS-232 protocol library.\n"
        "Proxied by terra-view at /api/sfm/*."
    ),
    version="0.1.0",
)


# ── Serialisers ────────────────────────────────────────────────────────────────
# Plain dict helpers — avoids a Pydantic dependency in the library layer.

def _serialise_timestamp(ts: Optional[Timestamp]) -> Optional[dict]:
    if ts is None:
        return None
    return {
        "year": ts.year,
        "month": ts.month,
        "day": ts.day,
        "clock_set": ts.clock_set,
        "display": str(ts),
    }


def _serialise_peak_values(pv: Optional[PeakValues]) -> Optional[dict]:
    if pv is None:
        return None
    return {
        "tran_in_s": pv.tran,
        "vert_in_s": pv.vert,
        "long_in_s": pv.long,
        "micl_psi":  pv.micl,
    }


def _serialise_project_info(pi: Optional[ProjectInfo]) -> Optional[dict]:
    if pi is None:
        return None
    return {
        "setup_name":      pi.setup_name,
        "project":         pi.project,
        "client":          pi.client,
        "operator":        pi.operator,
        "sensor_location": pi.sensor_location,
        "notes":           pi.notes,
    }


def _serialise_device_info(info: DeviceInfo) -> dict:
    return {
        "serial":           info.serial,
        "firmware_version": info.firmware_version,
        "firmware_minor":   info.firmware_minor,
        "dsp_version":      info.dsp_version,
        "manufacturer":     info.manufacturer,
        "model":            info.model,
    }


def _serialise_event(ev: Event) -> dict:
    return {
        "index":        ev.index,
        "timestamp":    _serialise_timestamp(ev.timestamp),
        "sample_rate":  ev.sample_rate,
        "record_type":  ev.record_type,
        "peak_values":  _serialise_peak_values(ev.peak_values),
        "project_info": _serialise_project_info(ev.project_info),
    }


# ── Transport factory ─────────────────────────────────────────────────────────

def _build_client(
    port: Optional[str],
    baud: int,
    host: Optional[str],
    tcp_port: int,
) -> MiniMateClient:
    """
    Return a MiniMateClient configured for either serial or TCP transport.

    TCP takes priority if *host* is supplied; otherwise *port* (serial) is used.
    Raises HTTPException(422) if neither is provided.
    """
    if host:
        # TCP / modem / ACH path
        transport = TcpTransport(host, port=tcp_port)
        log.debug("TCP transport: %s:%d", host, tcp_port)
        return MiniMateClient(transport=transport)
    elif port:
        # Direct serial path
        log.debug("Serial transport: %s baud=%d", port, baud)
        return MiniMateClient(port, baud)
    else:
        raise HTTPException(
            status_code=422,
            detail=(
                "Specify either 'port' (serial, e.g. ?port=COM5) "
                "or 'host' (TCP, e.g. ?host=192.168.1.50&tcp_port=12345)"
            ),
        )


# ── Endpoints ──────────────────────────────────────────────────────────────────

@app.get("/health")
def health() -> dict:
    """Service heartbeat.  No device I/O."""
    return {"status": "ok", "service": "sfm", "version": "0.1.0"}


@app.get("/device/info")
def device_info(
    port:     Optional[str] = Query(None,          description="Serial port (e.g. COM5, /dev/ttyUSB0)"),
    baud:     int           = Query(38400,          description="Serial baud rate (default 38400)"),
    host:     Optional[str] = Query(None,          description="TCP host — modem IP or ACH relay (e.g. 203.0.113.5)"),
    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
) -> dict:
    """
    Connect to the device, perform the POLL startup handshake, and return
    identity information (serial number, firmware version, model).

    Supply either *port* (serial) or *host* (TCP/modem).
    Equivalent to POST /device/connect — provided as GET for convenience.
    """
    log.info("GET /device/info  port=%s host=%s tcp_port=%d", port, host, tcp_port)

    try:
        with _build_client(port, baud, host, tcp_port) as client:
            info = client.connect()
    except HTTPException:
        raise
    except ProtocolError as exc:
        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
    except OSError as exc:
        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
    except Exception as exc:
        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc

    return _serialise_device_info(info)


@app.post("/device/connect")
def device_connect(
    port:     Optional[str] = Query(None,          description="Serial port (e.g. COM5)"),
    baud:     int           = Query(38400,          description="Serial baud rate"),
    host:     Optional[str] = Query(None,          description="TCP host — modem IP or ACH relay"),
    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
) -> dict:
    """
    Connect to the device and return identity.  POST variant for terra-view
    compatibility with the SLMM proxy pattern.
    """
    return device_info(port=port, baud=baud, host=host, tcp_port=tcp_port)


@app.get("/device/events")
def device_events(
    port:     Optional[str] = Query(None,          description="Serial port (e.g. COM5)"),
    baud:     int           = Query(38400,          description="Serial baud rate"),
    host:     Optional[str] = Query(None,          description="TCP host — modem IP or ACH relay"),
    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
) -> dict:
    """
    Connect to the device, read the event index, and download all stored
    events (event headers + full waveform records with peak values).

    Supply either *port* (serial) or *host* (TCP/modem).

    This does NOT download raw ADC waveform samples — those are large and
    fetched separately via GET /device/event/{idx}/waveform (future endpoint).
    """
    log.info("GET /device/events  port=%s host=%s", port, host)

    try:
        with _build_client(port, baud, host, tcp_port) as client:
            info   = client.connect()
            events = client.get_events()
    except HTTPException:
        raise
    except ProtocolError as exc:
        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
    except OSError as exc:
        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
    except Exception as exc:
        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc

    return {
        "device":      _serialise_device_info(info),
        "event_count": len(events),
        "events":      [_serialise_event(ev) for ev in events],
    }


@app.get("/device/event/{index}")
def device_event(
    index:    int,
    port:     Optional[str] = Query(None,          description="Serial port (e.g. COM5)"),
    baud:     int           = Query(38400,          description="Serial baud rate"),
    host:     Optional[str] = Query(None,          description="TCP host — modem IP or ACH relay"),
    tcp_port: int           = Query(DEFAULT_TCP_PORT, description=f"TCP port (default {DEFAULT_TCP_PORT})"),
) -> dict:
    """
    Download a single event by index (0-based).

    Supply either *port* (serial) or *host* (TCP/modem).
    Performs: POLL startup → event index → event header → waveform record.
    """
    log.info("GET /device/event/%d  port=%s host=%s", index, port, host)

    try:
        with _build_client(port, baud, host, tcp_port) as client:
            client.connect()
            events = client.get_events()
    except HTTPException:
        raise
    except ProtocolError as exc:
        raise HTTPException(status_code=502, detail=f"Protocol error: {exc}") from exc
    except OSError as exc:
        raise HTTPException(status_code=502, detail=f"Connection error: {exc}") from exc
    except Exception as exc:
        raise HTTPException(status_code=500, detail=f"Device error: {exc}") from exc

    matching = [ev for ev in events if ev.index == index]
    if not matching:
        raise HTTPException(
            status_code=404,
            detail=f"Event index {index} not found on device",
        )

    return _serialise_event(matching[0])


# ── Entry point ────────────────────────────────────────────────────────────────

if __name__ == "__main__":
    import argparse

    ap = argparse.ArgumentParser(description="SFM — Seismograph Field Module API server")
    ap.add_argument("--host", default="0.0.0.0", help="Bind address (default: 0.0.0.0)")
    ap.add_argument("--port", type=int, default=8200, help="Port (default: 8200)")
    ap.add_argument("--reload", action="store_true", help="Enable auto-reload (dev mode)")
    args = ap.parse_args()

    log.info("Starting SFM server on %s:%d", args.host, args.port)
    uvicorn.run(
        "sfm.server:app",
        host=args.host,
        port=args.port,
        reload=args.reload,
    )