#!/usr/bin/env python3
from __future__ import annotations

import math
import re
from pathlib import Path


ROOT = Path("/home/user/Desktop")
EXPECTED = (0.0, 39.9, 0.071472)
REL_TOL = 2.0e-3
ABS_TOL = 2.0e-5


def read(path: Path) -> str:
    return path.read_text(encoding="utf-8", errors="ignore")


def close(
    actual: float,
    expected: float,
    rel_tol: float = REL_TOL,
    abs_tol: float = ABS_TOL,
) -> bool:
    return math.isfinite(actual) and abs(actual - expected) <= max(
        abs_tol, rel_tol * max(1.0, abs(expected))
    )


def parameter(text: str, name: str) -> str:
    match = re.search(
        rf"^\s*(\S+).*?\s{re.escape(name)}\s+-",
        text,
        re.MULTILINE,
    )
    if not match:
        raise ValueError(f"missing parameter {name}")
    return match.group(1).strip('"').rstrip(",")


def output_metrics(path: Path) -> tuple[float, float, float]:
    lines = read(path).splitlines()
    if "at commit v5.0.0" not in "\n".join(lines[:5]):
        raise ValueError("output was not generated by OpenFAST 5.0.0")

    header_index = next(
        index
        for index, line in enumerate(lines)
        if line.split()[:1] == ["Time"]
    )
    headers = lines[header_index].split()
    units = lines[header_index + 1].split()
    time_i = headers.index("Time")
    power_i = headers.index("GenPwr")
    speed_i = headers.index("RotSpeed")
    pitch_indices = [
        headers.index(f"BldPitch{blade}")
        for blade in (1, 2, 3)
    ]
    if (
        units[time_i] != "(s)"
        or units[power_i] != "(kW)"
        or units[speed_i] != "(rpm)"
        or any(units[index] != "(deg)" for index in pitch_indices)
    ):
        raise ValueError("unexpected native OpenFAST units")

    rows: list[list[float]] = []
    for line in lines[header_index + 2 :]:
        fields = line.split()
        if len(fields) != len(headers):
            continue
        try:
            rows.append([float(value) for value in fields])
        except ValueError:
            continue
    if len(rows) != 901:
        raise ValueError("incorrect output sample count")
    for index, row in enumerate(rows):
        if not close(
            row[time_i],
            index / 10.0,
            rel_tol=0.0,
            abs_tol=2.0e-8,
        ):
            raise ValueError("output timestamps are not 0.1-second samples")

    shutdown_rows = rows[200:]
    if abs(rows[199][power_i]) < 100.0:
        raise ValueError("generator was already disconnected before 20 seconds")
    power_time = next(
        row[time_i] - 20.0
        for row in shutdown_rows
        if abs(row[power_i]) < 100.0
    )
    feather_time = next(
        row[time_i] - 20.0
        for row in shutdown_rows
        if all(row[index] >= 89.9 for index in pitch_indices)
    )

    for row in shutdown_rows:
        pitches = [row[index] for index in pitch_indices]
        if max(pitches) - min(pitches) > 2.0e-6:
            raise ValueError("blade pitch trajectories are not collective")
    if any(
        not close(rows[-1][index], 90.0, rel_tol=0.0, abs_tol=2.0e-6)
        for index in pitch_indices
    ):
        raise ValueError("final blade pitch is not 90 degrees")
    return power_time, feather_time, abs(rows[-1][speed_i])


def parse_summary(path: Path) -> tuple[float, float, float]:
    rows = [line.strip() for line in read(path).splitlines() if line.strip()]
    if len(rows) != 1:
        raise ValueError("summary must contain exactly one row")
    values = tuple(float(field.strip()) for field in rows[0].split(","))
    if len(values) != 3 or not all(math.isfinite(value) for value in values):
        raise ValueError("summary must contain three finite values")
    return values


def check() -> bool:
    required = (
        "build_case.py",
        "postprocess.py",
        "inflow_shutdown.dat",
        "elasto_shutdown.dat",
        "aero_shutdown.dat",
        "servo_shutdown.dat",
        "shutdown_case.fst",
        "shutdown_case.out",
        "shutdown_case.log",
        "summary.txt",
    )
    if any(
        not (ROOT / name).is_file() or (ROOT / name).stat().st_size == 0
        for name in required
    ):
        return False

    inflow = read(ROOT / "inflow_shutdown.dat")
    expected_inflow = {
        "WindType": "1",
        "HWindSpeed": "15.0",
    }
    if any(
        parameter(inflow, name) != value
        for name, value in expected_inflow.items()
    ):
        return False

    elasto = read(ROOT / "elasto_shutdown.dat")
    if parameter(elasto, "RotSpeed") != "12.1":
        return False
    if '"../5MW_Baseline/' in elasto:
        return False
    if any(
        f'"{channel}"' not in elasto
        for channel in ("BldPitch1", "BldPitch2", "BldPitch3", "RotSpeed")
    ):
        return False
    if '"../5MW_Baseline/' in read(ROOT / "aero_shutdown.dat"):
        return False

    servo = read(ROOT / "servo_shutdown.dat")
    expected_servo = {
        "GenTiStp": "True",
        "TimGenOf": "20.0",
        "HSSBrMode": "0",
        "TPitManS(1)": "20.0",
        "TPitManS(2)": "20.0",
        "TPitManS(3)": "20.0",
        "PitManRat(1)": "2.0",
        "PitManRat(2)": "2.0",
        "PitManRat(3)": "2.0",
        "BlPitchF(1)": "90.0",
        "BlPitchF(2)": "90.0",
        "BlPitchF(3)": "90.0",
    }
    if any(
        parameter(servo, name) != value
        for name, value in expected_servo.items()
    ):
        return False
    if '"GenPwr"' not in servo or '"../5MW_Baseline/' in servo:
        return False

    main = read(ROOT / "shutdown_case.fst")
    expected_main = {
        "TMax": "90.0",
        "DT_Out": "0.1",
        "OutFileFmt": "1",
        "EDFile": "elasto_shutdown.dat",
        "InflowFile": "inflow_shutdown.dat",
        "AeroFile": "aero_shutdown.dat",
        "ServoFile": "servo_shutdown.dat",
    }
    if any(
        parameter(main, name) != value
        for name, value in expected_main.items()
    ):
        return False

    log = read(ROOT / "shutdown_case.log")
    if (
        "OpenFAST-v5.0.0" not in log
        or "OpenFAST terminated normally." not in log
        or "Simulated Time:        90 seconds" not in log
        or "FATAL ERROR" in log
    ):
        return False

    calculated = output_metrics(ROOT / "shutdown_case.out")
    reported = parse_summary(ROOT / "summary.txt")
    return (
        all(
            close(actual, expected)
            for actual, expected in zip(calculated, EXPECTED)
        )
        and all(
            close(actual, expected)
            for actual, expected in zip(reported, EXPECTED)
        )
        and all(
            close(
                actual,
                calculated_value,
                rel_tol=0.0,
                abs_tol=2.0e-6,
            )
            for actual, calculated_value in zip(reported, calculated)
        )
    )


def main() -> int:
    try:
        result = check()
    except Exception:
        result = False
    print("True" if result else "False")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())