from __future__ import annotations

import io
import json
import zipfile
from pathlib import Path

import pytest
import requests

from backend.app import mineru_client
from backend.app.mineru_client import MineruClient, MineruClientError


class FakeResponse:
    def __init__(self, status: int, body: bytes):
        self.status = status
        self._body = body

    def read(self) -> bytes:
        return self._body

    def __enter__(self) -> "FakeResponse":
        return self

    def __exit__(self, *_args: object) -> None:
        return None


class FakeRequestsResponse:
    def __init__(self, status_code: int, text: str = ""):
        self.status_code = status_code
        self.text = text


def _zip_with_json() -> bytes:
    buffer = io.BytesIO()
    with zipfile.ZipFile(buffer, "w") as archive:
        archive.writestr(
            "demo_middle.json",
            json.dumps({"pdf_info": [{"page_idx": 0, "page_size": [1, 1], "para_blocks": []}]}),
        )
    return buffer.getvalue()


def _zip_with_layout_and_model() -> bytes:
    buffer = io.BytesIO()
    with zipfile.ZipFile(buffer, "w") as archive:
        archive.writestr("demo_model.json", json.dumps([[{"type": "header"}]]))
        archive.writestr(
            "layout.json",
            json.dumps({"pdf_info": [{"page_idx": 0, "page_size": [2, 2], "para_blocks": []}]}),
        )
    return buffer.getvalue()


def test_submit_pdf_downloads_and_loads_structured_json(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    calls: list[str] = []

    def fake_urlopen(request_obj, timeout=0):
        url = request_obj.full_url if hasattr(request_obj, "full_url") else request_obj
        calls.append(str(url))
        if str(url).endswith("/api/v4/file-urls/batch"):
            return FakeResponse(
                200,
                json.dumps(
                    {"code": 0, "data": {"batch_id": "batch-1", "file_urls": ["https://upload.example/file"]}}
                ).encode(),
            )
        if str(url) == "https://upload.example/file":
            raise AssertionError("upload URL should be handled by requests.put")
        if str(url).endswith("/api/v4/extract/task"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"task_id": "task-1"}}).encode(),
            )
        if str(url).endswith("/api/v4/extract/task/task-1"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"state": "done", "full_zip_url": "https://download.example/result.zip"}}).encode(),
            )
        if str(url) == "https://download.example/result.zip":
            return FakeResponse(200, _zip_with_json())
        raise AssertionError(f"unexpected URL {url}")

    monkeypatch.setattr(mineru_client.request, "urlopen", fake_urlopen)
    monkeypatch.setattr(mineru_client.requests, "put", lambda url, data, timeout=0: FakeRequestsResponse(200))
    pdf_path = tmp_path / "preview.pdf"
    pdf_path.write_bytes(b"%PDF-1.7")

    payload = MineruClient(api_key="secret", poll_interval_seconds=0, max_polls=1).parse_pdf(pdf_path, tmp_path)

    assert payload["pdf_info"][0]["page_size"] == [1, 1]
    assert calls == [
        "https://mineru.net/api/v4/file-urls/batch",
        "https://mineru.net/api/v4/extract/task",
        "https://mineru.net/api/v4/extract/task/task-1",
        "https://download.example/result.zip",
    ]
    assert (tmp_path / "mineru_result.zip").exists()


def test_submit_pdf_raises_on_failed_task(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    def fake_urlopen(request_obj, timeout=0):
        url = request_obj.full_url if hasattr(request_obj, "full_url") else request_obj
        if str(url).endswith("/api/v4/file-urls/batch"):
            return FakeResponse(
                200,
                json.dumps(
                    {"code": 0, "data": {"batch_id": "batch-1", "file_urls": ["https://upload.example/file"]}}
                ).encode(),
            )
        if str(url) == "https://upload.example/file":
            raise AssertionError("upload URL should be handled by requests.put")
        if str(url).endswith("/api/v4/extract/task"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"task_id": "task-1"}}).encode(),
            )
        if str(url).endswith("/api/v4/extract/task/task-1"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"state": "failed", "err_msg": "bad pdf"}}).encode(),
            )
        raise AssertionError(f"unexpected URL {url}")

    monkeypatch.setattr(mineru_client.request, "urlopen", fake_urlopen)
    monkeypatch.setattr(mineru_client.requests, "put", lambda url, data, timeout=0: FakeRequestsResponse(200))
    pdf_path = tmp_path / "preview.pdf"
    pdf_path.write_bytes(b"%PDF-1.7")

    with pytest.raises(MineruClientError, match="bad pdf"):
        MineruClient(api_key="secret", poll_interval_seconds=0, max_polls=1).parse_pdf(pdf_path, tmp_path)


def test_submit_pdf_raises_on_upload_http_error(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    def fake_urlopen(request_obj, timeout=0):
        url = request_obj.full_url if hasattr(request_obj, "full_url") else request_obj
        if str(url).endswith("/api/v4/file-urls/batch"):
            return FakeResponse(
                200,
                json.dumps(
                    {"code": 0, "data": {"batch_id": "batch-1", "file_urls": ["https://upload.example/file"]}}
                ).encode(),
            )
        raise AssertionError(f"unexpected URL {url}")

    monkeypatch.setattr(mineru_client.request, "urlopen", fake_urlopen)
    monkeypatch.setattr(
        mineru_client.requests,
        "put",
        lambda url, data, timeout=0: FakeRequestsResponse(403, "SignatureDoesNotMatch"),
    )
    pdf_path = tmp_path / "preview.pdf"
    pdf_path.write_bytes(b"%PDF-1.7")

    with pytest.raises(MineruClientError, match="HTTP 403"):
        MineruClient(api_key="secret", poll_interval_seconds=0, max_polls=1).parse_pdf(pdf_path, tmp_path)


def test_submit_pdf_prefers_layout_json_over_model_json(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    def fake_urlopen(request_obj, timeout=0):
        url = request_obj.full_url if hasattr(request_obj, "full_url") else request_obj
        if str(url).endswith("/api/v4/file-urls/batch"):
            return FakeResponse(
                200,
                json.dumps(
                    {"code": 0, "data": {"batch_id": "batch-1", "file_urls": ["https://upload.example/file"]}}
                ).encode(),
            )
        if str(url).endswith("/api/v4/extract/task"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"task_id": "task-1"}}).encode(),
            )
        if str(url).endswith("/api/v4/extract/task/task-1"):
            return FakeResponse(
                200,
                json.dumps({"code": 0, "data": {"state": "done", "full_zip_url": "https://download.example/result.zip"}}).encode(),
            )
        if str(url) == "https://download.example/result.zip":
            return FakeResponse(200, _zip_with_layout_and_model())
        raise AssertionError(f"unexpected URL {url}")

    monkeypatch.setattr(mineru_client.request, "urlopen", fake_urlopen)
    monkeypatch.setattr(mineru_client.requests, "put", lambda url, data, timeout=0: FakeRequestsResponse(200))
    pdf_path = tmp_path / "preview.pdf"
    pdf_path.write_bytes(b"%PDF-1.7")

    payload = MineruClient(api_key="secret", poll_interval_seconds=0, max_polls=1).parse_pdf(pdf_path, tmp_path)

    assert payload["pdf_info"][0]["page_size"] == [2, 2]