import json
import os
import sys
from pathlib import Path
from urllib.request import Request, HTTPRedirectHandler, build_opener
from urllib.parse import urljoin, urlsplit


class NoRedirect(HTTPRedirectHandler):
    def redirect_request(self, req, fp, code, msg, headers, newurl):
        return None


origin = os.environ.get("STASHBAY_ORIGIN", "https://stashbay.net").rstrip("/")
key = os.environ["STASHBAY_API_KEY"]
path = Path(sys.argv[1])
client = build_opener(NoRedirect)


def api(route, body):
    request = Request(origin + "/api/v1" + route, method="POST",
                      data=json.dumps(body).encode(),
                      headers={"Authorization": "Bearer " + key,
                               "Content-Type": "application/json"})
    with client.open(request, timeout=300) as response:
        return json.load(response)


size = path.stat().st_size
with path.open("rb") as file:
    plan = api("/uploads/init", {"filename": path.name, "sizeBytes": size})
    print("Upload ID:", plan["fileId"], file=sys.stderr)
    if not 1 <= plan["partSize"] <= 64 * 1024 * 1024:
        raise ValueError("Unexpected part size")
    parts = []
    for number in range(1, plan["partCount"] + 1):
        length = min(plan["partSize"], size - (number - 1) * plan["partSize"])
        data = file.read(length)
        if len(data) != length:
            raise ValueError("File changed during upload")
        address = plan["uploadUrl"] if plan["single"] else api(
            "/uploads/parts", {"fileId": plan["fileId"], "from": number, "count": 1}
        )["parts"][0]["url"]
        url = urljoin(origin, address)
        target, base = urlsplit(url), urlsplit(origin)
        headers = {"Content-Type": "application/octet-stream"}
        if plan["strategy"] == "proxy" and (target.scheme, target.netloc) == (base.scheme, base.netloc):
            headers["Authorization"] = "Bearer " + key
        elif plan["strategy"] != "presigned" or target.scheme != "https":
            raise ValueError("Unexpected upload URL or strategy")
        if plan["single"] and plan["strategy"] == "presigned":
            headers["If-None-Match"] = "*"
        with client.open(Request(url, data=data, headers=headers, method="PUT"), timeout=300) as response:
            if not plan["single"]:
                etag = json.load(response)["etag"] if plan["strategy"] == "proxy" else response.headers.get("ETag")
                if not etag:
                    raise ValueError("Missing part ETag")
                parts.append({"partNumber": number, "etag": etag.strip('"')})
    result = api("/uploads/complete", {"fileId": plan["fileId"], "parts": parts})
    print(result.get("shareUrl") or json.dumps(result))