"""Tests for lib/pr_state.py — centralized PR state transitions."""

import asyncio
import sqlite3
import sys
import os
from unittest.mock import AsyncMock, MagicMock, patch

import pytest

# Mock heavy dependencies before importing pr_state
sys.modules.setdefault("aiohttp", MagicMock())

# Add lib parent to path so `lib.pr_state` resolves
sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))

from lib.pr_state import (
    approve_pr,
    close_pr,
    mark_conflict,
    mark_conflict_permanent,
    mark_merged,
    reopen_pr,
    reset_for_reeval,
    start_fixing,
    start_review,
)


# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------

def _make_db():
    """Create a minimal in-memory DB with the prs table."""
    conn = sqlite3.connect(":memory:")
    conn.row_factory = sqlite3.Row
    conn.execute("""
        CREATE TABLE prs (
            number INTEGER PRIMARY KEY,
            source_path TEXT,
            branch TEXT,
            status TEXT NOT NULL DEFAULT 'open',
            domain TEXT,
            auto_merge INTEGER DEFAULT 0,
            leo_verdict TEXT DEFAULT 'pending',
            domain_verdict TEXT DEFAULT 'pending',
            eval_attempts INTEGER DEFAULT 0,
            eval_issues TEXT DEFAULT '[]',
            merge_cycled INTEGER DEFAULT 0,
            merge_failures INTEGER DEFAULT 0,
            conflict_rebase_attempts INTEGER DEFAULT 0,
            last_error TEXT,
            merged_at TEXT,
            last_attempt TEXT,
            tier0_pass INTEGER,
            fix_attempts INTEGER DEFAULT 0,
            cost_usd REAL DEFAULT 0,
            created_at TEXT DEFAULT (datetime('now'))
        )
    """)
    return conn


def _insert_pr(conn, number=100, status="open", domain=None, **kwargs):
    """Insert a test PR row."""
    cols = ["number", "status"]
    vals = [number, status]
    if domain is not None:
        cols.append("domain")
        vals.append(domain)
    for k, v in kwargs.items():
        cols.append(k)
        vals.append(v)
    placeholders = ", ".join(["?"] * len(vals))
    col_names = ", ".join(cols)
    conn.execute(f"INSERT INTO prs ({col_names}) VALUES ({placeholders})", vals)
    conn.commit()


def _get_pr(conn, number=100):
    """Read a PR row back."""
    return conn.execute("SELECT * FROM prs WHERE number = ?", (number,)).fetchone()


# ---------------------------------------------------------------------------
# close_pr
# ---------------------------------------------------------------------------

class TestClosePr:
    def test_close_calls_forgejo_and_updates_db(self):
        conn = _make_db()
        _insert_pr(conn, 42)

        mock_api = AsyncMock(return_value={})
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            asyncio.run(close_pr(conn, 42, last_error="test close"))

        row = _get_pr(conn, 42)
        assert row["status"] == "closed"
        assert row["last_error"] == "test close"
        mock_api.assert_called_once()

    def test_close_skips_forgejo_when_opted_out(self):
        conn = _make_db()
        _insert_pr(conn, 42)

        mock_api = AsyncMock(return_value={})
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            asyncio.run(close_pr(conn, 42, last_error="reconciled", close_on_forgejo=False))

        row = _get_pr(conn, 42)
        assert row["status"] == "closed"
        mock_api.assert_not_called()

    def test_close_increments_merge_failures(self):
        conn = _make_db()
        _insert_pr(conn, 42, merge_failures=2)

        mock_api = AsyncMock(return_value={})
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            asyncio.run(close_pr(conn, 42, merge_cycled=True, inc_merge_failures=True))

        row = _get_pr(conn, 42)
        assert row["merge_cycled"] == 1
        assert row["merge_failures"] == 3

    def test_close_without_last_error(self):
        conn = _make_db()
        _insert_pr(conn, 42, last_error="old error")

        mock_api = AsyncMock(return_value={})
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            result = asyncio.run(close_pr(conn, 42))

        assert result is True
        row = _get_pr(conn, 42)
        assert row["status"] == "closed"
        # last_error not overwritten when not provided
        assert row["last_error"] == "old error"

    def test_close_returns_false_on_forgejo_failure(self):
        """Critical: if Forgejo API fails, DB must NOT be updated (ghost PR prevention)."""
        conn = _make_db()
        _insert_pr(conn, 42)

        mock_api = AsyncMock(return_value=None)  # forgejo_api returns None on failure
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            result = asyncio.run(close_pr(conn, 42, last_error="should not persist"))

        assert result is False
        row = _get_pr(conn, 42)
        assert row["status"] == "open"  # DB not touched
        assert row["last_error"] is None  # last_error not set

    def test_close_skips_forgejo_check_when_opted_out(self):
        """close_on_forgejo=False always succeeds (caller already closed Forgejo)."""
        conn = _make_db()
        _insert_pr(conn, 42)

        mock_api = AsyncMock(return_value=None)  # would fail if called
        with patch("lib.pr_state.forgejo_api", mock_api), \
             patch("lib.pr_state.repo_path", lambda s: f"/repos/test/{s}"):
            result = asyncio.run(close_pr(conn, 42, close_on_forgejo=False))

        assert result is True
        row = _get_pr(conn, 42)
        assert row["status"] == "closed"
        mock_api.assert_not_called()


# ---------------------------------------------------------------------------
# approve_pr
# ---------------------------------------------------------------------------

class TestApprovePr:
    def test_approve_sets_domain_and_auto_merge(self):
        conn = _make_db()
        _insert_pr(conn, 50)

        approve_pr(conn, 50, domain="internet-finance", auto_merge=1)

        row = _get_pr(conn, 50)
        assert row["status"] == "approved"
        assert row["domain"] == "internet-finance"
        assert row["auto_merge"] == 1

    def test_approve_raises_on_empty_domain(self):
        conn = _make_db()
        _insert_pr(conn, 50)

        with pytest.raises(ValueError, match="without domain"):
            approve_pr(conn, 50, domain="")

    def test_approve_raises_on_none_domain(self):
        conn = _make_db()
        _insert_pr(conn, 50)

        with pytest.raises(ValueError, match="without domain"):
            approve_pr(conn, 50, domain=None)

    def test_approve_sets_verdicts(self):
        conn = _make_db()
        _insert_pr(conn, 50)

        approve_pr(conn, 50, domain="cross-domain", auto_merge=1,
                   leo_verdict="skipped", domain_verdict="skipped")

        row = _get_pr(conn, 50)
        assert row["leo_verdict"] == "skipped"
        assert row["domain_verdict"] == "skipped"

    def test_approve_preserves_existing_domain(self):
        conn = _make_db()
        _insert_pr(conn, 50, domain="living-agents")

        approve_pr(conn, 50, domain="cross-domain", auto_merge=0)

        row = _get_pr(conn, 50)
        # COALESCE(domain, ?) preserves existing domain
        assert row["domain"] == "living-agents"


# ---------------------------------------------------------------------------
# mark_merged
# ---------------------------------------------------------------------------

class TestMarkMerged:
    def test_sets_merged_at_and_clears_error(self):
        conn = _make_db()
        _insert_pr(conn, 60, status="approved", last_error="some old error")

        mark_merged(conn, 60)

        row = _get_pr(conn, 60)
        assert row["status"] == "merged"
        assert row["merged_at"] is not None
        assert row["last_error"] is None


# ---------------------------------------------------------------------------
# mark_conflict
# ---------------------------------------------------------------------------

class TestMarkConflict:
    def test_increments_failures_and_sets_cycled(self):
        conn = _make_db()
        _insert_pr(conn, 70, status="approved", merge_failures=0)

        mark_conflict(conn, 70, last_error="cherry-pick failed")

        row = _get_pr(conn, 70)
        assert row["status"] == "conflict"
        assert row["merge_cycled"] == 1
        assert row["merge_failures"] == 1
        assert row["last_error"] == "cherry-pick failed"

    def test_accumulates_failures(self):
        conn = _make_db()
        _insert_pr(conn, 70, merge_failures=5)

        mark_conflict(conn, 70)

        row = _get_pr(conn, 70)
        assert row["merge_failures"] == 6


# ---------------------------------------------------------------------------
# mark_conflict_permanent
# ---------------------------------------------------------------------------

class TestMarkConflictPermanent:
    def test_sets_status_and_attempts(self):
        conn = _make_db()
        _insert_pr(conn, 80, status="conflict")

        mark_conflict_permanent(conn, 80,
                                last_error="rebase failed 3x",
                                conflict_rebase_attempts=3)

        row = _get_pr(conn, 80)
        assert row["status"] == "conflict_permanent"
        assert row["last_error"] == "rebase failed 3x"
        assert row["conflict_rebase_attempts"] == 3


# ---------------------------------------------------------------------------
# reopen_pr
# ---------------------------------------------------------------------------

class TestReopenPr:
    def test_simple_reopen(self):
        conn = _make_db()
        _insert_pr(conn, 90, status="reviewing")

        reopen_pr(conn, 90)

        row = _get_pr(conn, 90)
        assert row["status"] == "open"

    def test_reopen_with_rejection(self):
        conn = _make_db()
        _insert_pr(conn, 90, status="reviewing")

        reopen_pr(conn, 90, leo_verdict="skipped",
                  last_error="domain rejected",
                  eval_issues='["factual_error"]')

        row = _get_pr(conn, 90)
        assert row["status"] == "open"
        assert row["leo_verdict"] == "skipped"
        assert row["last_error"] == "domain rejected"
        assert row["eval_issues"] == '["factual_error"]'

    def test_reopen_dec_eval_attempts(self):
        conn = _make_db()
        _insert_pr(conn, 90, status="reviewing", eval_attempts=3)

        reopen_pr(conn, 90, dec_eval_attempts=True)

        row = _get_pr(conn, 90)
        assert row["eval_attempts"] == 2

    def test_reopen_reset_for_reeval(self):
        conn = _make_db()
        _insert_pr(conn, 90, status="conflict",
                   leo_verdict="approve", domain_verdict="approve",
                   eval_attempts=2)

        reopen_pr(conn, 90, reset_for_reeval=True,
                  conflict_rebase_attempts=1)

        row = _get_pr(conn, 90)
        assert row["status"] == "open"
        assert row["leo_verdict"] == "pending"
        assert row["domain_verdict"] == "pending"
        assert row["eval_attempts"] == 0
        assert row["conflict_rebase_attempts"] == 1


# ---------------------------------------------------------------------------
# start_review
# ---------------------------------------------------------------------------

class TestStartReview:
    def test_claims_open_pr(self):
        conn = _make_db()
        _insert_pr(conn, 100)

        assert start_review(conn, 100) is True

        row = _get_pr(conn, 100)
        assert row["status"] == "reviewing"

    def test_rejects_non_open_pr(self):
        conn = _make_db()
        _insert_pr(conn, 100, status="reviewing")

        assert start_review(conn, 100) is False

    def test_double_claim_fails(self):
        conn = _make_db()
        _insert_pr(conn, 100)

        assert start_review(conn, 100) is True
        assert start_review(conn, 100) is False


# ---------------------------------------------------------------------------
# start_fixing
# ---------------------------------------------------------------------------

class TestStartFixing:
    def test_claims_open_pr(self):
        conn = _make_db()
        _insert_pr(conn, 200)

        assert start_fixing(conn, 200) is True

        row = _get_pr(conn, 200)
        assert row["status"] == "fixing"
        assert row["fix_attempts"] == 1

    def test_increments_fix_attempts(self):
        conn = _make_db()
        _insert_pr(conn, 200, fix_attempts=3)

        assert start_fixing(conn, 200) is True

        row = _get_pr(conn, 200)
        assert row["fix_attempts"] == 4

    def test_sets_last_attempt(self):
        conn = _make_db()
        _insert_pr(conn, 200)

        start_fixing(conn, 200)

        row = _get_pr(conn, 200)
        assert row["last_attempt"] is not None

    def test_rejects_non_open_pr(self):
        conn = _make_db()
        _insert_pr(conn, 200, status="reviewing")

        assert start_fixing(conn, 200) is False

    def test_double_claim_fails(self):
        conn = _make_db()
        _insert_pr(conn, 200)

        assert start_fixing(conn, 200) is True
        assert start_fixing(conn, 200) is False


# ---------------------------------------------------------------------------
# reset_for_reeval
# ---------------------------------------------------------------------------

class TestResetForReeval:
    def test_resets_all_eval_state(self):
        conn = _make_db()
        _insert_pr(conn, 300, status="fixing",
                   eval_attempts=3, leo_verdict="request_changes",
                   domain_verdict="approve")
        conn.execute(
            "UPDATE prs SET eval_issues = ?, tier0_pass = 1, last_error = 'some error' WHERE number = 300",
            ('["broken_wiki_links"]',),
        )

        reset_for_reeval(conn, 300)

        row = _get_pr(conn, 300)
        assert row["status"] == "open"
        assert row["eval_attempts"] == 0
        assert row["eval_issues"] == "[]"
        assert row["tier0_pass"] is None
        assert row["domain_verdict"] == "pending"
        assert row["leo_verdict"] == "pending"
        assert row["last_error"] is None

    def test_preserves_non_eval_fields(self):
        conn = _make_db()
        _insert_pr(conn, 300, status="fixing", domain="internet-finance",
                   fix_attempts=2)

        reset_for_reeval(conn, 300)

        row = _get_pr(conn, 300)
        assert row["domain"] == "internet-finance"
        assert row["fix_attempts"] == 2