#!/usr/bin/env python3
#
# conc_local.py --- Short-Range Dispersion Simulations
#                   See HYSPLIT Tutorial Sec. 17.4
#
# Change history:
# 11 May 2026 (BB) - standard-aligned, cross-platform version
# 16 Jun 2026 (SZ) - create image files when DSP=NO
# 18 Jun 2026 (SZ) - standardize code for run_cmd(), convert_html_to_img(),
#                    etc. across Python scripts
#                  - ensure encoding is specified when opening files

import os
import sys
import platform
from pathlib import Path
import subprocess
import webbrowser

if sys.version_info < (3, 8):
    print("Please use Python 3.8 or higher.")
    sys.exit(1)

system = platform.system().lower()
if system == "windows":
    PGM = Path(sys.argv[1]) if len(sys.argv) > 1 else Path("C:\\hysplit")
    OUT = Path(sys.argv[2]) if len(sys.argv) > 2 else PGM / "working"
    DSP = sys.argv[3] if len(sys.argv) > 3 else "YES"
    TTR = Path(os.environ.get("TTR", "C:\\Tutorial"))
    exe_suffix = ".exe"
else:
    PGM = Path(sys.argv[1]) if len(sys.argv) > 1 else Path.home() / "hysplit"
    OUT = Path(sys.argv[2]) if len(sys.argv) > 2 else PGM / "working"
    DSP = sys.argv[3] if len(sys.argv) > 3 else "YES"
    TTR = Path(os.environ.get("TTR", Path.home() / "tutorial"))
    exe_suffix = ""

if not PGM.exists():
    script = Path(__file__).name if "__file__" in globals() else "conc_local.py"
    print(f"ERROR: HYSPLIT not found at {PGM}")
    print(f"""
Please specify the path to your HYSPLIT installation using a command-line argument:

python {script} YOUR_HYSPLIT_DIRECTORY [OUT] [DSP (YES|NO)]

Example:
    python {script} C:\\hysplit C:\\hysplit\\working YES
""")
    sys.exit(1)

if not TTR.exists():
    print(f"ERROR: HYSPLIT tutorial not found at {TTR}")
    print("""
Please set the TTR environment variable to point to your HYSPLIT tutorial directory.

For Windows users (Command Prompt):
   SET TTR=YOUR_HYSPLIT_TUTORIAL_DIRECTORY

For Linux users (bash shell):
   export TTR='YOUR_HYSPLIT_TUTORIAL_DIRECTORY'

For Linux users (csh or tcsh shell):
   setenv TTR 'YOUR_HYSPLIT_TUTORIAL_DIRECTORY'""")
    sys.exit(1)

os.chdir(OUT)


# ------------------------------------------------------------------
# Helper functions
# ------------------------------------------------------------------

def run_cmd(cmd, desc="", allow_fail=False, stdout_file=None, append=False):
    if desc:
        print(f"{desc}...")

    exitcode = 0
    with subprocess.Popen(cmd,
                         stdout=subprocess.PIPE,
                         stderr=subprocess.STDOUT,
                         text=True) as p:
        if stdout_file:
            mode="a" if append else "w"
            with open(stdout_file, mode, encoding="utf-8") as f_out:
                for ln in p.stdout:
                    print(ln, end="")
                    f_out.write(ln)
        else:
            with p.stdout as f:
                for ln in iter(f.readline, b'\n'):
                    if len(ln) == 0:
                        break
                    print(ln.rstrip())

        done = False
        while not done:
            try:
                exitcode = p.wait(timeout=1)
                done = True
            except subprocess.TimeoutExpired:
                print("WARN: subprocess timed out.")

    if exitcode != 0:
        if allow_fail:
            print(f"WARN: command failed with exit code {exitcode} -> {' '.join(cmd)}")
        else:
            print(f"ERROR: command failed with exit code {exitcode} -> {' '.join(cmd)}")
            sys.exit(1)


def convert_html_to_img(html_file, img_name_frame_nums):
    # Split SVG into Linux-consistent naming: F00-sec71_001.svg, etc.
    temp_img_name = "temp"
    run_cmd([str(PGM / "exec" / f"splitsvg{exe_suffix}"),
             f"-i{html_file}", f"-o{temp_img_name}.svg"])

    # Locate ImageMagick for cross-platform conversion
    if system == "windows":
        convert_exe = None
        imgk_dir = next(
            (k for k in os.environ.get('PATH', '').split(os.pathsep)
             if "ImageMagick" in k),
            None
        )
        if imgk_dir:
            # Use magick.exe for ImageMagick 7.x and later. Use convert.exe for earlier versions.
            for cmd in ('magick', 'convert'):
                candidate = os.path.join(imgk_dir, f'{cmd}{exe_suffix}')
                if os.path.exists(candidate):
                    convert_exe = candidate
                    break
    else:
        convert_exe = "convert"

    if convert_exe:
        # Match Linux naming for DSP=NO mode exactly
        for img_name, frame_num in img_name_frame_nums:
            svg = Path(f"F{frame_num:02d}-{temp_img_name}.svg")
            run_cmd([convert_exe, str(svg), img_name])
            print(f"Converted {svg} -> {img_name}")
            svg.unlink()
    else:
        print("ImageMagick not found — skipping .svg conversion")


def find_met_dir(dat_name: str):
    env_override = os.environ.get("METDIR")
    candidates = []

    if env_override:
        candidates.append(Path(env_override))

    candidates += [
        wrk / "sage",
        TTR / "sage",
        TTR,
        PGM / "tutorial" / "sage",
        PGM / "tutorial",
        OUT / "sage",
        PGM / "met",
        PGM / "meteorology",
    ]

    for base in candidates:
        if base and (base / dat_name).exists():
            return base

    for root in [TTR, wrk, PGM]:
        try:
            for p in Path(root).rglob(dat_name):
                return p.parent
        except Exception:
            pass

    return None


# ---------- Mirror BAT variables ----------
wrk = OUT.parent

syr, smo, sda, shr = 13, 10, 18, 19
lat, lon, lvl = 43.59066, -112.938, 10.0
run, top = 3, 10000.0

dat = "sage5_wrf01.bin"

met = find_met_dir(dat)

if met is None:
    print(f"ERROR: Meteorological file not found: {dat}")
    print("Set METDIR to the directory containing the file.")
    print("Example Windows: SET METDIR=C:\\Tutorial\\sage")
    sys.exit(1)

meas_file = met / "sage5_meas.txt"
if not meas_file.exists():
    print(f"Warning: measurement file not found at {meas_file}")

# Clean files
for fname in [
    "ASCDATA.CFG",
    "CONTROL",
    "SETUP.CFG",
    "LABELS.CFG",
    "cdump",
    "sage5.txt",
    "statA.txt",
    "dataA.txt",
    "scatter.html",
    "concplot.html",
]:
    p = OUT / fname
    if p.exists():
        p.unlink()

# ASCDATA.CFG
with open(OUT / "ASCDATA.CFG", "w", encoding="ascii") as f:
    f.write("-90.0   -180.0  lat/lon of lower left corner  \n")
    f.write("1.0     1.0     lat/lon spacing in degrees    \n")
    f.write("180     360     lat/lon number of data points \n")
    f.write("2               default land use category     \n")
    f.write("0.2             default roughness length (m)  \n")
    f.write(f"'{PGM / 'bdyfiles'}{os.sep}'  directory of files\n")

# CONTROL
odir = f".{os.sep}"

with open(OUT / "CONTROL", "w", encoding="ascii") as f:
    f.write(f"{syr:02d} {smo:02d} {sda:02d} {shr:02d}\n")
    f.write("1\n")
    f.write(f"{lat:.5f} {lon:.3f} {lvl:.1f}\n")
    f.write(f"{run}\n")
    f.write("0\n")
    f.write(f"{top:.1f}\n")
    f.write("1\n")
    f.write(f"{met}{os.sep}\n")
    f.write(f"{dat}\n")
    f.write("1\n")
    f.write("SF6E\n")
    f.write("3708.0\n")
    f.write("2.5\n")
    f.write("13 10 18 19 30\n")
    f.write("1\n")
    f.write("43.59 -112.94\n")
    f.write("0.001 0.001\n")
    f.write("0.2 0.2\n")
    f.write(f"{odir}\n")
    f.write("cdump\n")
    f.write("1\n")
    f.write("25\n")
    f.write("13 10 18 20 00\n")
    f.write("13 10 18 22 00\n")
    f.write("00 00 10\n")
    f.write("1\n")
    f.write("0.0 0.0 0.0\n")
    f.write("0.0 0.0 0.0 0.0 0.0\n")
    f.write("0.0 0.0 0.0\n")
    f.write("0.0\n")
    f.write("0.0\n")

# SETUP.CFG
with open(OUT / "SETUP.CFG", "w", encoding="ascii") as f:
    f.write("&SETUP\n")
    f.write("initd = 0,\n")
    f.write("kbls = 1,\n")
    f.write("kblt = 2,\n")
    f.write("numpar = 50000,\n")
    f.write("maxpar = 100000,\n")
    f.write("cpack = 1,\n")
    f.write("ichem = 6,\n")
    f.write("/\n")

# Run model
run_cmd(
    [str(PGM / "exec" / f"hycs_std{exe_suffix}")],
    "Running hycs_std"
)

# Statistics
run_cmd([
    str(PGM / "exec" / f"c2datem{exe_suffix}"),
    "-icdump",
    "-xi",
    "-osage5.txt",
    "-c1.986E+08",
    f"-m{meas_file}",
], "Creating DATEM file")

run_cmd([
    str(PGM / "exec" / f"statmain{exe_suffix}"),
    "-t0",
    "-rsage5.txt",
    f"-d{meas_file}",
    "-l10.0",
    "-o1",
], "Running statistics")

# Scatter plot
run_cmd([
    str(PGM / "exec" / f"scatter{exe_suffix}"),
    "+g1",
    "-idataA.txt",
    "-p10.0",
], "Creating scatter plot")

scatter_html = OUT / "scatter.html"
if scatter_html.exists():
    if DSP == "YES":
        webbrowser.open(str(scatter_html.resolve()))
    else:
        convert_html_to_img(str(scatter_html), [("sage010.png",1)])

if DSP == "YES":
    input("Press Enter to continue...")

stat_file = OUT / "statA.txt"
if stat_file.exists():
    print("\n--- statA.txt ---\n")
    print(stat_file.read_text(encoding="ascii", errors="replace"))
else:
    print("Warning: statA.txt not generated")

if DSP == "YES":
    input("Press Enter to continue...")

# LABELS.CFG
with open(OUT / "LABELS.CFG", "w", encoding="ascii") as f:
    f.write(f"'TITLE&','### {Path(sys.argv[0]).name} ### &'\n")
    f.write("'LAYER&',' between &'\n")
    f.write("'UNITS&','ppt&'\n")
    f.write("'VOLUM&','&'\n")
    f.write("'RELEASE&','SF6&'\n")

# Concentration plot
run_cmd([
    str(PGM / "exec" / f"concplot{exe_suffix}"),
    "+g1",
    "-icdump",
    f"-j{PGM / 'graphics' / 'arlmap'}",
    "-z100",
    "-x1.986E+08",
    "-g5:1",
    "-c4",
    "-v10000+5000+2000+1000+500+200+100+50+20+10",
    f"-q{meas_file}",
], "Creating concentration plot")

conc_html = OUT / "concplot.html"
if conc_html.exists():
    if DSP == "YES":
        webbrowser.open(str(conc_html.resolve()))
    else:
        convert_html_to_img(str(conc_html), [("sage013.png",1)])

if DSP == "YES":
    input("Press Enter to continue...")

# Concentration plot - zoom in the previous plot
run_cmd([
    str(PGM / "exec" / f"concplot{exe_suffix}"),
    "+g1",
    "-icdump",
    f"-j{PGM / 'graphics' / 'arlmap'}",
    "-z100",
    "-x1.986E+08",
    "-H43.6:-112.94",
    "-g3:1",
    "-c4",
    "-v10000+5000+2000+1000+500+200+100+50+20+10",
    f"-q{meas_file}",
], "Creating concentration plot")

conc_html = OUT / "concplot.html"
if conc_html.exists():
    if DSP == "YES":
        webbrowser.open(str(conc_html.resolve()))
    else:
        convert_html_to_img(str(conc_html), [("sage014.png",1)])

print("\nScript completed successfully!")