from __future__ import annotations

import hashlib
import json
import os
from pathlib import Path
import unittest

from app.main import compile_system_xml_network
from app.simulation.benchmark_regression import (
    evaluate_regression_golden,
    load_regression_manifest,
    run_regression_suite,
    source_simulation_config,
)
from app.simulation.systems.generic import GenericFluidSystem
from app.system_xml import validate_system_xml_document


MANIFEST_PATH = Path(
    "tests/baselines/simulation/test_mql_full_branches/manifest.json"
)
LONG_RUN_ENVIRONMENT = "RUN_TEST_MQL_FULL_BRANCHES_LONG_REGRESSION"


class MqlFullBranchesStaticRegressionTests(unittest.TestCase):
    @classmethod
    def setUpClass(cls) -> None:
        cls.manifest = load_regression_manifest(MANIFEST_PATH)
        cls.source_path = Path(cls.manifest["_sourcePath"])
        cls.source_payload = cls.source_path.read_bytes()
        cls.validation = validate_system_xml_document(cls.source_payload)

    def test_authoritative_xml_hash_and_simulation_settings_are_fixed(self) -> None:
        source = self.manifest["source"]

        self.assertEqual(
            hashlib.sha256(self.source_payload).hexdigest(), source["sha256"]
        )
        self.assertEqual(len(self.source_payload), source["bytes"])
        self.assertEqual(
            source_simulation_config(self.source_payload), source["simulation"]
        )

    def test_structure_snapshot_covers_the_historical_solver_shape(self) -> None:
        self.assertTrue(self.validation.valid, self.validation.as_dict())
        assert self.validation.document is not None
        network = compile_system_xml_network(self.validation.document)
        system = GenericFluidSystem(network)
        expected = self.manifest["structure"]
        pressure_flow = network.pressure_flow_structure_dict()
        causal_execution = system.pressure_flow_solver.causal_execution_diagnostics()
        jacobian = system.jacobian_sparsity_diagnostics()

        self.assertEqual(len(network.components), expected["componentCount"])
        self.assertEqual(len(network.connections), expected["connectionCount"])
        self.assertEqual(
            len(network.dynamic_components()), expected["dynamicComponentCount"]
        )
        self.assertEqual(
            sum(component.state_size for component in network.dynamic_components()),
            expected["stateCount"],
        )
        self.assertEqual(
            len(network.result_variable_metadata()), expected["resultVariableCount"]
        )
        self.assertEqual(
            pressure_flow["unknownCount"], expected["pressureFlowUnknownCount"]
        )
        self.assertEqual(
            pressure_flow["equationCount"], expected["pressureFlowEquationCount"]
        )
        self.assertEqual(pressure_flow["isSquare"], expected["pressureFlowIsSquare"])
        for key in (
            "logicalEffortCoordinateCount",
            "eliminatedEffortAliasCount",
            "canonicalCoordinateCount",
            "compatibilityScatterCount",
        ):
            self.assertEqual(causal_execution[key], expected[key])
        self.assertEqual(jacobian["nonzeroCount"], expected["jacobianNonzeroCount"])
        self.assertEqual(
            jacobian["colorGroupCount"], expected["jacobianColorGroupCount"]
        )
        self.assertEqual(
            system.mechanical_state_reducer.has_state_events,
            expected["hasMechanicalStateEvents"],
        )

    def test_three_production_repeats_replay_approved_goldens_exactly(self) -> None:
        repository_root = Path(self.manifest["_repositoryRoot"])
        evidence = self.manifest["acceptanceEvidence"]
        self.assertEqual(evidence["status"], "approved")
        self.assertEqual(evidence["lane"], "production")
        self.assertEqual(evidence["repeatCount"], 3)
        self.assertTrue(evidence["physicalValuesIdenticalAcrossRepeats"])

        expected_counts = {"0.81s": 480, "2.10s": 720}
        stable_signatures: dict[str, object] = {}
        for report_reference in evidence["reports"]:
            report_path = repository_root / report_reference["path"]
            payload = report_path.read_bytes()
            self.assertEqual(len(payload), report_reference["bytes"])
            self.assertEqual(
                hashlib.sha256(payload).hexdigest(),
                report_reference["sha256"],
            )
            report = json.loads(payload)
            self.assertEqual(report["lane"], "production")
            self.assertEqual(
                report["source"]["sha256"], self.manifest["source"]["sha256"]
            )

            for case_id in self.manifest["sequence"]:
                case = next(
                    item for item in report["cases"] if item["caseId"] == case_id
                )
                self.assertEqual(case["outcome"], "completed")
                self.assertTrue(case["acceptance"]["passed"])
                summary = case["worker"]["summary"]
                golden = self.manifest["_goldens"][case_id]["production"]
                audit = evaluate_regression_golden(summary, golden)
                self.assertTrue(audit["passed"], audit)
                self.assertEqual(
                    audit["comparedValueCount"], expected_counts[case_id]
                )
                self.assertEqual(audit["maxAbsoluteError"], 0.0)
                self.assertEqual(audit["maxToleranceRatio"], 0.0)
                self.assertEqual(audit["issues"], [])

                diagnostics = dict(summary["diagnostics"])
                diagnostics.pop("performance", None)
                signature = {
                    "physicalContract": summary["physicalContract"],
                    "eventTrace": summary["eventTrace"],
                    "outputContract": summary["outputContract"],
                    "diagnosticsWithoutPerformance": diagnostics,
                }
                if case_id not in stable_signatures:
                    stable_signatures[case_id] = signature
                else:
                    self.assertEqual(stable_signatures[case_id], signature)

    def test_both_horizons_have_the_expected_signal_schedule(self) -> None:
        assert self.validation.document is not None
        system = GenericFluidSystem(
            compile_system_xml_network(self.validation.document)
        )

        for case_id in self.manifest["sequence"]:
            variant = self.manifest["variants"][case_id]
            actual = system.signal_resolver.event_times(
                0.0, float(variant["stopTime"])
            )
            self.assertEqual(actual, tuple(variant["expectedSignalEventTimes"]))


@unittest.skipUnless(
    os.getenv(LONG_RUN_ENVIRONMENT, "").strip().lower() in {"1", "true", "yes"},
    f"Set {LONG_RUN_ENVIRONMENT}=1 to run bounded 0.81/2.10 s integration.",
)
class MqlFullBranchesLongRegressionTests(unittest.TestCase):
    def test_both_horizons_complete_within_their_safety_budgets(self) -> None:
        report = run_regression_suite(MANIFEST_PATH, lane="production")
        outcomes = [case["outcome"] for case in report["cases"]]
        self.assertEqual(outcomes, ["completed", "completed"], report["cases"])
        self.assertTrue(
            all(
                case["acceptance"]["regressionGolden"]["passed"]
                for case in report["cases"]
            ),
            report["cases"],
        )


if __name__ == "__main__":
    unittest.main()