#!/usr/bin/env python3
"""Rebuild data/misc/country.tsv from datasets/country-codes (PDDL).

    data-import/country.py [--source URL_OR_FILE] [--out FILE]
"""
import argparse
import csv
import io
import re
import sys
import urllib.request
from pathlib import Path

SOURCE = "https://raw.githubusercontent.com/datasets/country-codes/main/data/country-codes.csv"
OUT = Path(__file__).resolve().parent.parent / "data" / "misc" / "country.tsv"
COLUMNS = ["alpha2", "alpha3", "calling-code", "capital", "currency", "flag", "languages", "name", "numeric", "tld"]
# Gaps in the source, keyed by alpha2.
FIXUPS = {"TR": {"currency": "TRY"}}


def read(source):
    if re.match(r"^https?://", source):
        with urllib.request.urlopen(source, timeout=60) as r:
            return r.read().decode("utf-8")
    return Path(source).read_text(encoding="utf-8")


def flag(alpha2):
    return "".join(chr(0x1F1E6 + ord(c) - ord("A")) for c in alpha2)


def calling_code(dial):
    first = re.sub(r"[^0-9-]", "", dial.split(",")[0])
    return first if re.match(r"^\d+-\d{3}$", first) else first.split("-")[0]


def languages(field):
    return ",".join(p for p in field.split(",") if p)


def rows(text):
    for r in csv.DictReader(io.StringIO(text)):
        alpha2 = r["ISO3166-1-Alpha-2"]
        row = {
            "alpha2": alpha2,
            "alpha3": r["ISO3166-1-Alpha-3"],
            "calling-code": calling_code(r["Dial"]),
            "capital": r["Capital"],
            "currency": r["ISO4217-currency_alphabetic_code"].split(",")[0],
            "flag": flag(alpha2),
            "languages": languages(r["Languages"]),
            "name": r["CLDR display name"] or r["official_name_en"],
            "numeric": r["ISO3166-1-numeric"].zfill(3),
            "tld": r["TLD"],
        }
        row.update(FIXUPS.get(alpha2, {}))
        if all(row[c] for c in ("alpha2", "alpha3", "calling-code", "capital", "currency", "name", "tld")):
            yield row


def write(out, table):
    lines = ["\t".join(COLUMNS)]
    for row in sorted(table, key=lambda r: r["alpha2"]):
        cells = [row[c] for c in COLUMNS]
        assert not any("\t" in c or "\n" in c for c in cells), row
        lines.append("\t".join(cells))
    Path(out).write_text("\n".join(lines) + "\n", encoding="utf-8")
    return len(lines) - 1


def main():
    p = argparse.ArgumentParser(description=__doc__.splitlines()[0])
    p.add_argument("--source", default=SOURCE)
    p.add_argument("--out", default=str(OUT))
    a = p.parse_args()
    n = write(a.out, rows(read(a.source)))
    print(f"{a.out}: {n} rows", file=sys.stderr)


if __name__ == "__main__":
    main()