import os
import io
import uuid
import asyncio
from time import sleep
import sys
from pathlib import Path

import pytest
from fastapi.testclient import TestClient

# Ensure required env vars for app import/config
os.environ.setdefault("SECRET_KEY", "x" * 32)
os.environ.setdefault("DATABASE_URL", "sqlite:////tmp/delphi_test.sqlite")

ROOT = Path(__file__).resolve().parents[1]
if str(ROOT) not in sys.path:
    sys.path.insert(0, str(ROOT))

from app.main import app  # noqa: E402
from app.auth.security import get_current_user  # noqa: E402
from app.config import settings  # noqa: E402
from app.services.template_search import TemplateSearchService  # noqa: E402


def _dummy_docx_bytes():
    try:
        from docx import Document  # type: ignore
    except Exception:
        return b"PK\x03\x04"
    d = Document()
    p = d.add_paragraph()
    p.add_run("Cache Test ")
    p.add_run("{{TOKEN}}")
    buf = io.BytesIO()
    d.save(buf)
    return buf.getvalue()


def _upload_template(client: TestClient, name: str, category: str = "GENERAL") -> int:
    files = {"file": (f"{name}.docx", _dummy_docx_bytes(), "application/vnd.openxmlformats-officedocument.wordprocessingml.document")}
    resp = client.post(
        "/api/templates/upload",
        data={"name": name, "category": category, "semantic_version": "1.0.0"},
        files=files,
    )
    assert resp.status_code == 200, resp.text
    return int(resp.json()["id"])


@pytest.fixture()
def client_no_redis():
    class _User:
        def __init__(self):
            self.id = "tmpl-cache-user"
            self.username = "tester"
            self.is_admin = True
            self.is_active = True

    app.dependency_overrides[get_current_user] = lambda: _User()
    # Disable Redis to exercise in-memory fallback
    settings.cache_enabled = False
    settings.redis_url = ""
    # Clear template caches
    try:
        asyncio.run(TemplateSearchService.invalidate_all())
    except Exception:
        pass
    try:
        yield TestClient(app)
    finally:
        app.dependency_overrides.pop(get_current_user, None)


def test_templates_search_caches_in_memory(client_no_redis: TestClient):
    # Upload in unique category to avoid interference
    category = f"CAT_{uuid.uuid4().hex[:8]}"
    _upload_template(client_no_redis, f"T-{uuid.uuid4().hex[:6]}", category)

    params = {"category": category}
    r1 = client_no_redis.get("/api/templates/search", params=params)
    assert r1.status_code == 200
    d1 = r1.json()

    # Second call should be served from cache and be identical
    r2 = client_no_redis.get("/api/templates/search", params=params)
    assert r2.status_code == 200
    d2 = r2.json()
    assert d1 == d2


def test_templates_search_invalidation_on_upload_in_memory(client_no_redis: TestClient):
    # Use unique empty category; first query caches empty list
    category = f"EMPTY_{uuid.uuid4().hex[:8]}"
    r_empty = client_no_redis.get("/api/templates/search", params={"category": category})
    assert r_empty.status_code == 200
    assert r_empty.json() == []

    # Upload a template into that category -> triggers invalidation
    _upload_template(client_no_redis, f"New-{uuid.uuid4().hex[:6]}", category)
    sleep(0.05)

    # Query again should reflect the new item (cache invalidated)
    r_after = client_no_redis.get("/api/templates/search", params={"category": category})
    assert r_after.status_code == 200
    ids = [it["id"] for it in r_after.json()]
    assert len(ids) >= 1


def test_templates_search_invalidation_on_keyword_update_in_memory(client_no_redis: TestClient):
    category = f"KW_{uuid.uuid4().hex[:8]}"
    tid = _upload_template(client_no_redis, f"KW-{uuid.uuid4().hex[:6]}", category)

    # Initial query has_keywords=true should be empty and cached
    r1 = client_no_redis.get("/api/templates/search", params={"category": category, "has_keywords": True})
    assert r1.status_code == 200
    assert r1.json() == []

    # Add a keyword to the template -> invalidates caches
    r_add = client_no_redis.post(f"/api/templates/{tid}/keywords", json={"keywords": ["alpha"]})
    assert r_add.status_code == 200
    sleep(0.05)

    # Now search with has_keywords=true should include our template
    r2 = client_no_redis.get("/api/templates/search", params={"category": category, "has_keywords": True})
    assert r2.status_code == 200
    ids2 = {it["id"] for it in r2.json()}
    assert tid in ids2


@pytest.fixture()
def client_with_redis():
    if not settings.redis_url:
        pytest.skip("Redis not configured for caching tests")

    class _User:
        def __init__(self):
            self.id = "tmpl-cache-user-redis"
            self.username = "tester"
            self.is_admin = True
            self.is_active = True

    app.dependency_overrides[get_current_user] = lambda: _User()
    settings.cache_enabled = True
    # Clear template caches
    try:
        asyncio.run(TemplateSearchService.invalidate_all())
    except Exception:
        pass
    try:
        yield TestClient(app)
    finally:
        app.dependency_overrides.pop(get_current_user, None)


def test_templates_search_caches_with_redis(client_with_redis: TestClient):
    category = f"RCAT_{uuid.uuid4().hex[:8]}"
    _upload_template(client_with_redis, f"RT-{uuid.uuid4().hex[:6]}", category)

    params = {"category": category}
    r1 = client_with_redis.get("/api/templates/search", params=params)
    assert r1.status_code == 200
    d1 = r1.json()

    r2 = client_with_redis.get("/api/templates/search", params=params)
    assert r2.status_code == 200
    d2 = r2.json()
    assert d1 == d2


def test_templates_search_invalidation_on_upload_with_redis(client_with_redis: TestClient):
    category = f"RADD_{uuid.uuid4().hex[:8]}"
    r_empty = client_with_redis.get("/api/templates/search", params={"category": category})
    assert r_empty.status_code == 200 and r_empty.json() == []

    _upload_template(client_with_redis, f"RNew-{uuid.uuid4().hex[:6]}", category)
    sleep(0.05)

    r_after = client_with_redis.get("/api/templates/search", params={"category": category})
    assert r_after.status_code == 200
    assert len(r_after.json()) >= 1


def test_templates_search_invalidation_on_keyword_update_with_redis(client_with_redis: TestClient):
    category = f"RKW_{uuid.uuid4().hex[:8]}"
    tid = _upload_template(client_with_redis, f"RTKW-{uuid.uuid4().hex[:6]}", category)

    r1 = client_with_redis.get("/api/templates/search", params={"category": category, "has_keywords": True})
    assert r1.status_code == 200 and r1.json() == []

    r_add = client_with_redis.post(f"/api/templates/{tid}/keywords", json={"keywords": ["beta"]})
    assert r_add.status_code == 200
    sleep(0.05)

    r2 = client_with_redis.get("/api/templates/search", params={"category": category, "has_keywords": True})
    ids = {it["id"] for it in r2.json()}
    assert tid in ids