from __future__ import annotations

import json
from pathlib import Path

import requests

from github_datapipe.config import GithubConfig
from github_datapipe.extract_repos import SampleReposOptions, resolve_query, sample_repositories


def test_resolve_query_uses_default_when_missing() -> None:
    """ Verifies that an empty or missing query string falls back to the config default. """
    assert resolve_query(None) == GithubConfig.default_query


def test_resolve_query_uses_override_when_present() -> None:
    """ Verifies that a user-provided query overrides the config default. """
    assert resolve_query("stars:>50") == "stars:>50"


def test_sample_repositories_dedupes_and_persists(monkeypatch, tmp_path: Path) -> None:
    """
    Tests the core data pipeline: ensures pagination works, duplicates are 
    ignored across pages, and data is correctly saved to the file system.
    """

    # ==========================================
    # ARRANGE
    # ==========================================
    monkeypatch.setenv("github_token", "token")

    # Create a mock GitHub API that returns 3 total repos across 2 pages.
    # Notice that 'repo-one' (ID 100) is returned twice to test deduplication.
    class FakeSampler:
        def __init__(self, token: str, session: requests.Session | None = None) -> None:
            self.token = token

        def search_repositories(self, query: str, page: int, per_page: int) -> dict:
            if page == 1:
                return {
                    "total_count": 3,
                    "items": [
                        fake_repo(100, "owner/repo-one"),
                        fake_repo(100, "owner/repo-one"),
                        fake_repo(101, "owner/repo-two"),
                    ],
                }
            return {"total_count": 3, "items": [fake_repo(102, "owner/repo-three")]}

    # Inject the mock sampler into the main code
    monkeypatch.setattr("github_datapipe.extract_repos.GithubRepoSampler", FakeSampler)

    options = SampleReposOptions(
        count=3,
        output_root=tmp_path, # Safely write files to a temporary test folder
        query="stars:>10",
        mode="append-deduped",
        run_id="run-test",
    )

    # ==========================================
    # ACT
    # ==========================================

    result = sample_repositories(options)

    # ==========================================
    # ASSERT
    # ==========================================
    repos_path = Path(result["repos_path"])
    rows = [json.loads(line) for line in repos_path.read_text(encoding="utf-8").splitlines()]
    assert len(rows) == 3
    assert [row["repo_id"] for row in rows] == [100, 101, 102]

    seen_path = tmp_path / "seen_repo_ids.json"
    seen_payload = json.loads(seen_path.read_text(encoding="utf-8"))
    assert seen_payload == [100, 101, 102]


def fake_repo(repo_id: int, full_name: str) -> dict:
    """
    Helper function to generate a mock GitHub repository payload.
    Provides only the fields required by the `normalize_repo_record` function.
    """
    return {
        "id": repo_id,
        "full_name": full_name,
        "html_url": f"https://github.com/{full_name}",
        "url": f"https://api.github.com/repos/{full_name}",
        "default_branch": "main",
        "language": "Python",
        "description": f"Description for {full_name}",
        "stargazers_count": 42,
        "size": 2048,
        "fork": False,
        "archived": False,
        "visibility": "public",
    }