"""Download all hero portraits from Steam CDN as fallback templates.

Usage:
    python fetch_cdn_templates.py

Writes:
    heroes.json            - hero id / key / English name table (from OpenDota constants)
    templates/cdn/{key}.png - face-centered square crop resized to canonical size
"""

import json
from pathlib import Path

import cv2
import numpy as np
import requests

from common import ROOT, TEMPLATES_CDN, load_config

# Valve's own feed: ids, localized names, primary attribute. The hero-selection
# grid groups by that attribute and sorts by that localized name, so taking both
# from the same source is what lets grid.py place every cell without matching.
HEROES_URL = "https://www.dota2.com/datafeed/herolist?language={lang}"
IMG_URL = "https://cdn.cloudflare.steamstatic.com/apps/dota2/images/dota_react/heroes/{key}.png"
ATTRS = {0: "str", 1: "agi", 2: "int", 3: "all"}

# The top bar shows a fixed window of the landscape hero art, not a centred
# square. These bounds were fitted against 15 portraits captured in game:
# they lift the mean match score from 0.65 to 0.94. Stored as fractions of
# the source width so they hold whatever size the CDN serves.
CROP_X0, CROP_X1 = 38 / 256, (38 + 182) / 256


def fetch_heroes(lang: str = "schinese") -> list[dict]:
    data = requests.get(HEROES_URL.format(lang=lang), timeout=30).json()
    heroes = data.get("result", {}).get("data", {}).get("heroes") or data.get("heroes")
    if not heroes:
        raise SystemExit("hero list came back empty")
    return heroes


def main() -> None:
    cfg = load_config()
    size = cfg["canonical_size"]
    TEMPLATES_CDN.mkdir(parents=True, exist_ok=True)

    print("fetching hero list from the Dota 2 data feed...")
    heroes = fetch_heroes()

    table = []
    ok, fail = 0, 0
    for h in heroes:
        key = h["name"].removeprefix("npc_dota_hero_")
        table.append({
            "id": h["id"],
            "key": key,
            "name": h["name_english_loc"],
            "attr": ATTRS.get(h["primary_attr"], "all"),
            "name_loc": h["name_loc"],
        })
        out = TEMPLATES_CDN / f"{key}.png"
        if out.exists():
            ok += 1
            continue
        try:
            raw = requests.get(IMG_URL.format(key=key), timeout=30).content
            img = cv2.imdecode(np.frombuffer(raw, np.uint8), cv2.IMREAD_COLOR)
            if img is None:
                raise ValueError("decode failed")
            iw = img.shape[1]
            window = img[:, int(iw * CROP_X0) : int(iw * CROP_X1)]
            cv2.imwrite(str(out), cv2.resize(window, (size, size), interpolation=cv2.INTER_AREA))
            ok += 1
        except Exception as e:  # noqa: BLE001
            print(f"  FAILED {key}: {e}")
            fail += 1

    with open(ROOT / "heroes.json", "w", encoding="utf-8") as f:
        json.dump(sorted(table, key=lambda t: t["id"]), f, ensure_ascii=False, indent=1)
    print(f"done: {ok} templates, {fail} failures, {len(table)} heroes in heroes.json")


if __name__ == "__main__":
    main()