"""FastAPI TestClient-based tests for accurate coverage measurement."""
from __future__ import annotations
import io, json, pytest
from fastapi.testclient import TestClient
from web.api import app

client = TestClient(app)


def test_index():
    r = client.get("/")
    assert r.status_code == 200
    assert "verify" in r.text.lower()


def test_verify_422_empty():
    r = client.post("/verify")
    assert r.status_code == 422


def test_verify_202():
    r = client.post("/verify",
        files={
            "copybook": ("t.cpy", b"x", "text/plain"),
            "cobol_src": ("t.cbl", b"x", "text/plain"),
            "java_src": ("t.java", b"x", "text/plain"),
            "mapping": ("t.yaml", b"x", "text/plain"),
        },
        data={"runner": "native"})
    assert r.status_code == 202
    body = r.json()
    assert "task_id" in body
    return body["task_id"]


def test_verify_large_file_413():
    r = client.post("/verify",
        files={
            "copybook": ("t.cpy", b"x", "text/plain"),
            "cobol_src": ("t.cbl", b"x" * (10 * 1024 * 1024 + 1), "application/octet-stream"),
            "java_src": ("t.java", b"x", "text/plain"),
            "mapping": ("t.yaml", b"x", "text/plain"),
        },
        data={"runner": "native"})
    assert r.status_code == 413


def test_status_404():
    r = client.get("/status/nonexistent")
    assert r.status_code == 404


def test_status_ok():
    tid = test_verify_202()
    r = client.get(f"/status/{tid}")
    assert r.status_code == 200
    body = r.json()
    assert body["status"] in ("queued", "running", "done", "error")


def test_fields_404():
    r = client.get("/fields/nonexistent")
    assert r.status_code == 404


def test_fields_ok():
    tid = test_verify_202()
    r = client.get(f"/fields/{tid}")
    assert r.status_code == 200
    body = r.json()
    assert "fields" in body
    assert "debug" in body
    assert "build_log" in body


def test_result_404():
    r = client.get("/result/nonexistent")
    assert r.status_code == 404


def test_result_page():
    tid = test_verify_202()
    r = client.get(f"/result/{tid}")
    assert r.status_code == 200
    assert tid in r.text


def test_static_css():
    r = client.get("/static/style.css")
    assert r.status_code == 200


def test_static_js():
    r = client.get("/static/script.js")
    assert r.status_code == 200