"""Tests for the managed proxy pool."""

import json
import time

import pytest

from s5p.config import ChainHop, PoolSourceConfig, ProxyPoolConfig
from s5p.pool import ProxyEntry, ProxyPool


class TestProxyEntry:
    """Test ProxyEntry defaults."""

    def test_defaults(self):
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        entry = ProxyEntry(hop=hop)
        assert entry.alive is False
        assert entry.fails == 0
        assert entry.tests == 0


class TestProxyPoolMerge:
    """Test proxy deduplication and merge."""

    def test_merge_dedup(self):
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        proxies = [
            ChainHop(proto="socks5", host="1.2.3.4", port=1080),
            ChainHop(proto="socks5", host="1.2.3.4", port=1080),
            ChainHop(proto="socks5", host="5.6.7.8", port=1080),
        ]
        pool._merge(proxies)
        assert pool.count == 2

    def test_merge_updates_existing(self):
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        pool._merge([hop])
        first_seen = pool._proxies["socks5://1.2.3.4:1080"].last_seen

        # merge again -- last_seen should update
        time.sleep(0.01)
        pool._merge([hop])
        assert pool._proxies["socks5://1.2.3.4:1080"].last_seen >= first_seen
        assert pool.count == 1


class TestProxyPoolGet:
    """Test proxy selection."""

    def test_get_empty(self):
        import asyncio

        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        result = asyncio.run(pool.get())
        assert result is None

    def test_get_returns_alive(self):
        import asyncio

        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        pool._proxies["socks5://1.2.3.4:1080"] = ProxyEntry(hop=hop, alive=True)
        pool._rebuild_alive()
        result = asyncio.run(pool.get())
        assert result is not None
        assert result.host == "1.2.3.4"


class TestProxyPoolWeight:
    """Test weighted proxy selection."""

    def test_recent_proxy_preferred(self):
        import asyncio
        from collections import Counter

        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)

        now = time.time()
        fresh = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        stale = ChainHop(proto="socks5", host="10.0.0.2", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=fresh, alive=True, last_ok=now,
        )
        pool._proxies["socks5://10.0.0.2:1080"] = ProxyEntry(
            hop=stale, alive=True, last_ok=now - 3600,
        )
        pool._rebuild_alive()

        counts: Counter[str] = Counter()
        for _ in range(1000):
            hop = asyncio.run(pool.get())
            counts[hop.host] += 1

        assert counts["10.0.0.1"] > counts["10.0.0.2"] * 3

    def test_weight_values(self):
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        now = 1000.0

        # just tested
        entry = ProxyEntry(hop=hop, last_ok=now)
        assert ProxyPool._weight(entry, now) == pytest.approx(1.0)

        # 5 minutes ago
        entry.last_ok = now - 300
        assert ProxyPool._weight(entry, now) == pytest.approx(0.5)

        # never tested
        entry.last_ok = 0
        assert ProxyPool._weight(entry, now) == pytest.approx(0.01)

    def test_weight_failure_penalty(self):
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        now = 1000.0

        # healthy proxy: weight ~1.0
        entry = ProxyEntry(hop=hop, last_ok=now)
        assert ProxyPool._weight(entry, now) == pytest.approx(1.0)

        # just failed: weight drops to floor (fail_age=0 -> multiplier=0)
        entry.last_fail = now
        assert ProxyPool._weight(entry, now) == pytest.approx(0.01)

        # 30s after failure: base=1/(1+30/300)=0.909, penalty=30/60=0.5 -> ~0.45
        assert ProxyPool._weight(entry, now + 30) == pytest.approx(0.4545, abs=0.05)

        # 60s after failure: penalty=1.0, only base decay -> 1/(1+60/300)=0.833
        assert ProxyPool._weight(entry, now + 60) == pytest.approx(0.833, abs=0.05)

    def test_report_failure(self):
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        pool._proxies["socks5://1.2.3.4:1080"] = ProxyEntry(
            hop=hop, alive=True, last_ok=time.time(),
        )

        assert pool._proxies["socks5://1.2.3.4:1080"].last_fail == 0.0
        pool.report_failure(hop)
        assert pool._proxies["socks5://1.2.3.4:1080"].last_fail > 0.0

    def test_report_failure_unknown_proxy(self):
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        hop = ChainHop(proto="socks5", host="9.9.9.9", port=1080)
        pool.report_failure(hop)  # should not raise


class TestProxyPoolHealthTests:
    """Test selective health testing."""

    def test_selective_keys(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)

        now = time.time()
        hop_a = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        hop_b = ChainHop(proto="socks5", host="10.0.0.2", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=hop_a, alive=False, last_seen=now,
        )
        pool._proxies["socks5://10.0.0.2:1080"] = ProxyEntry(
            hop=hop_b, alive=False, last_seen=now,
        )

        # only test proxy A
        with patch.object(pool, "_test_proxy", new_callable=AsyncMock, return_value=True) as mock:
            asyncio.run(pool._run_health_tests(keys=["socks5://10.0.0.1:1080"]))
            # should only have been called for proxy A
            assert mock.call_count == 1
            assert mock.call_args[0][0] == "socks5://10.0.0.1:1080"

        assert pool._proxies["socks5://10.0.0.1:1080"].alive is True
        # proxy B untouched
        assert pool._proxies["socks5://10.0.0.2:1080"].alive is False

    def test_chain_check_skips_on_failure(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        chain_hop = ChainHop(proto="socks5", host="127.0.0.1", port=9050)
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [chain_hop], timeout=10.0)

        now = time.time()
        hop = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=hop, alive=True, last_seen=now, last_ok=now,
        )
        pool._rebuild_alive()

        # chain test fails -> proxy tests should be skipped
        with (
            patch.object(pool, "_test_chain", new_callable=AsyncMock, return_value=False),
            patch.object(pool, "_test_proxy", new_callable=AsyncMock) as mock_proxy,
        ):
            asyncio.run(pool._run_health_tests())
            mock_proxy.assert_not_called()

        # proxy should remain in its previous state (untouched)
        assert pool._proxies["socks5://10.0.0.1:1080"].alive is True

    def test_chain_check_passes(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        chain_hop = ChainHop(proto="socks5", host="127.0.0.1", port=9050)
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [chain_hop], timeout=10.0)

        now = time.time()
        hop = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=hop, alive=False, last_seen=now,
        )

        # chain test passes -> proxy tests should run
        with (
            patch.object(pool, "_test_chain", new_callable=AsyncMock, return_value=True),
            patch.object(pool, "_test_proxy", new_callable=AsyncMock, return_value=True),
        ):
            asyncio.run(pool._run_health_tests())

        assert pool._proxies["socks5://10.0.0.1:1080"].alive is True

    def test_no_chain_skips_check(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)  # no static chain

        now = time.time()
        hop = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=hop, alive=False, last_seen=now,
        )

        # no chain -> _test_chain should not be called, proxy tests run
        with (
            patch.object(pool, "_test_chain", new_callable=AsyncMock) as mock_chain,
            patch.object(pool, "_test_proxy", new_callable=AsyncMock, return_value=True),
        ):
            asyncio.run(pool._run_health_tests())
            mock_chain.assert_not_called()

        assert pool._proxies["socks5://10.0.0.1:1080"].alive is True


class TestProxyPoolStaleExpiry:
    """Test stale proxy eviction."""

    def test_stale_dead_proxy_evicted(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        cfg = ProxyPoolConfig(sources=[], refresh=300)
        pool = ProxyPool(cfg, [], timeout=10.0)

        now = time.time()
        # stale + dead: should be evicted
        stale = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=stale, alive=False, last_seen=now - 1200,
        )
        # fresh + dead: should survive (recently seen, might recover)
        fresh_dead = ChainHop(proto="socks5", host="10.0.0.2", port=1080)
        pool._proxies["socks5://10.0.0.2:1080"] = ProxyEntry(
            hop=fresh_dead, alive=False, last_seen=now,
        )

        with patch.object(pool, "_test_proxy", new_callable=AsyncMock, return_value=False):
            asyncio.run(pool._run_health_tests())

        assert "socks5://10.0.0.1:1080" not in pool._proxies
        assert "socks5://10.0.0.2:1080" in pool._proxies

    def test_stale_alive_proxy_kept(self):
        import asyncio
        from unittest.mock import AsyncMock, patch

        cfg = ProxyPoolConfig(sources=[], refresh=300)
        pool = ProxyPool(cfg, [], timeout=10.0)

        now = time.time()
        # stale but alive: should survive (still passing health tests)
        hop = ChainHop(proto="socks5", host="10.0.0.1", port=1080)
        pool._proxies["socks5://10.0.0.1:1080"] = ProxyEntry(
            hop=hop, alive=True, last_seen=now - 1200, last_ok=now,
        )

        with patch.object(pool, "_test_proxy", new_callable=AsyncMock, return_value=True):
            asyncio.run(pool._run_health_tests())

        assert "socks5://10.0.0.1:1080" in pool._proxies


class TestProxyPoolFetchFile:
    """Test file source parsing."""

    def test_parse_file(self, tmp_path):
        proxy_file = tmp_path / "proxies.txt"
        proxy_file.write_text(
            "# comment\n"
            "socks5://1.2.3.4:1080\n"
            "socks5://user:pass@5.6.7.8:1080\n"
            "http://proxy.example.com:8080\n"
            "\n"
            "  # another comment\n"
        )
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        src = PoolSourceConfig(file=str(proxy_file))
        result = pool._fetch_file_sync(src)
        assert len(result) == 3
        assert result[0].proto == "socks5"
        assert result[0].host == "1.2.3.4"
        assert result[1].username == "user"
        assert result[1].password == "pass"
        assert result[2].proto == "http"

    def test_parse_file_with_proto_filter(self, tmp_path):
        proxy_file = tmp_path / "proxies.txt"
        proxy_file.write_text(
            "socks5://1.2.3.4:1080\n"
            "http://proxy.example.com:8080\n"
        )
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        src = PoolSourceConfig(file=str(proxy_file), proto="socks5")
        result = pool._fetch_file_sync(src)
        assert len(result) == 1
        assert result[0].proto == "socks5"

    def test_missing_file(self, tmp_path):
        cfg = ProxyPoolConfig(sources=[])
        pool = ProxyPool(cfg, [], timeout=10.0)
        src = PoolSourceConfig(file=str(tmp_path / "nonexistent.txt"))
        result = pool._fetch_file_sync(src)
        assert result == []


class TestProxyPoolPersistence:
    """Test state save/load."""

    def test_save_and_load(self, tmp_path):
        state_file = str(tmp_path / "pool.json")
        cfg = ProxyPoolConfig(sources=[], state_file=state_file)
        pool = ProxyPool(cfg, [], timeout=10.0)

        hop = ChainHop(proto="socks5", host="1.2.3.4", port=1080)
        pool._proxies["socks5://1.2.3.4:1080"] = ProxyEntry(
            hop=hop, alive=True, fails=0, tests=5, last_ok=1000.0,
        )
        pool._rebuild_alive()
        pool._save_state()

        # load into a fresh pool
        pool2 = ProxyPool(cfg, [], timeout=10.0)
        pool2._load_state()
        assert pool2.count == 1
        assert pool2.alive_count == 1
        entry = pool2._proxies["socks5://1.2.3.4:1080"]
        assert entry.hop.host == "1.2.3.4"
        assert entry.tests == 5
        assert entry.alive is True

    def test_corrupt_state(self, tmp_path):
        state_file = tmp_path / "pool.json"
        state_file.write_text("{invalid json")
        cfg = ProxyPoolConfig(sources=[], state_file=str(state_file))
        pool = ProxyPool(cfg, [], timeout=10.0)
        pool._load_state()
        assert pool.count == 0

    def test_missing_state(self, tmp_path):
        cfg = ProxyPoolConfig(sources=[], state_file=str(tmp_path / "missing.json"))
        pool = ProxyPool(cfg, [], timeout=10.0)
        pool._load_state()  # should not raise
        assert pool.count == 0

    def test_state_with_auth(self, tmp_path):
        state_file = str(tmp_path / "pool.json")
        cfg = ProxyPoolConfig(sources=[], state_file=state_file)
        pool = ProxyPool(cfg, [], timeout=10.0)

        hop = ChainHop(
            proto="socks5", host="1.2.3.4", port=1080,
            username="user", password="pass",
        )
        pool._proxies["socks5://1.2.3.4:1080"] = ProxyEntry(hop=hop, alive=True)
        pool._save_state()

        pool2 = ProxyPool(cfg, [], timeout=10.0)
        pool2._load_state()
        entry = pool2._proxies["socks5://1.2.3.4:1080"]
        assert entry.hop.username == "user"
        assert entry.hop.password == "pass"