/*
 * Copyright 2008-2026 Async-IO.org
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
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package org.atmosphere.ai.governance;

import org.atmosphere.ai.annotation.AgentScope;
import org.atmosphere.ai.governance.scope.ScopeConfig;
import org.atmosphere.ai.governance.scope.ScopePolicy;
import org.atmosphere.ai.governance.scope.RuleBasedScopeGuardrail;
import org.atmosphere.cpr.AtmosphereConfig;
import org.atmosphere.cpr.AtmosphereFramework;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertInstanceOf;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

/**
 * Verifies the tool-call admission seam — {@code PolicyAdmissionGate.admitToolCall}
 * builds a synthetic {@link org.atmosphere.ai.AiRequest} whose metadata carries
 * {@code tool_name} + {@code action}, so MS-schema rules targeting
 * {@code tool_name} fire before the tool executor runs. Covers
 * OWASP Agentic Top-10 A02 (Tool Misuse).
 */
class PolicyAdmissionGateToolCallTest {

    private AtmosphereFramework framework;
    private Map<String, Object> properties;

    @BeforeEach
    void setUp() {
        framework = mock(AtmosphereFramework.class);
        var config = mock(AtmosphereConfig.class);
        properties = new HashMap<>();
        when(framework.getAtmosphereConfig()).thenReturn(config);
        when(config.properties()).thenReturn(properties);
    }

    @Test
    void admitsWhenNoPoliciesInstalled() {
        var result = PolicyAdmissionGate.admitToolCall(framework, "search_documents",
                Map.of("query", "hello"));
        assertInstanceOf(PolicyAdmissionGate.Result.Admitted.class, result);
    }

    @Test
    void denyRuleOnToolNameFires() {
        // Classic MS Agent Governance example: deny delete_database tool calls.
        var policy = new org.atmosphere.ai.governance.MsAgentOsPolicy(
                "block-delete-database", "yaml:test", "1.0",
                List.of(new org.atmosphere.ai.governance.MsAgentOsPolicy.Rule(
                        "deny-delete", "tool_name",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Operator.EQ,
                        "delete_database", 100,
                        "Deleting databases is not allowed",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Action.DENY, null)),
                org.atmosphere.ai.governance.MsAgentOsPolicy.Action.ALLOW);
        properties.put(GovernancePolicy.POLICIES_PROPERTY, List.of(policy));

        var result = PolicyAdmissionGate.admitToolCall(framework, "delete_database",
                Map.of("table", "users"));

        var denied = assertInstanceOf(PolicyAdmissionGate.Result.Denied.class, result);
        assertEquals("block-delete-database", denied.policyName());
        assertTrue(denied.reason().toLowerCase().contains("deleting databases"));
    }

    @Test
    void allowedToolPasses() {
        var policy = new org.atmosphere.ai.governance.MsAgentOsPolicy(
                "tool-gate", "yaml:test", "1.0",
                List.of(new org.atmosphere.ai.governance.MsAgentOsPolicy.Rule(
                        "deny-delete", "tool_name",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Operator.EQ,
                        "delete_database", 100, "",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Action.DENY, null)),
                org.atmosphere.ai.governance.MsAgentOsPolicy.Action.ALLOW);
        properties.put(GovernancePolicy.POLICIES_PROPERTY, List.of(policy));

        var result = PolicyAdmissionGate.admitToolCall(framework, "search_documents",
                Map.of("query", "hello"));
        assertInstanceOf(PolicyAdmissionGate.Result.Admitted.class, result);
    }

    @Test
    void toolArgsPreviewOnMetadata() {
        // Audit-only rule that fires and lets admit pass through so we can
        // inspect the snapshot recorded to GovernanceDecisionLog.
        var policy = new org.atmosphere.ai.governance.MsAgentOsPolicy(
                "audit-tool", "yaml:test", "1.0",
                List.of(new org.atmosphere.ai.governance.MsAgentOsPolicy.Rule(
                        "audit-everything", "tool_name",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Operator.EQ,
                        "search", 10, "",
                        org.atmosphere.ai.governance.MsAgentOsPolicy.Action.AUDIT, null)),
                org.atmosphere.ai.governance.MsAgentOsPolicy.Action.ALLOW);
        properties.put(GovernancePolicy.POLICIES_PROPERTY, List.of(policy));

        GovernanceDecisionLog.install(10);
        try {
            var result = PolicyAdmissionGate.admitToolCall(framework, "search",
                    Map.of("q", "sensitive", "limit", 10));
            assertInstanceOf(PolicyAdmissionGate.Result.Admitted.class, result);

            var recent = GovernanceDecisionLog.installed().recent(5);
            assertEquals(1, recent.size());
            var snapshot = recent.get(0).contextSnapshot();
            assertEquals("search", snapshot.get("tool_name"));
            assertEquals("call_tool", snapshot.get("action"));
            assertTrue(((String) snapshot.get("tool_args_preview")).contains("sensitive"),
                    "tool args preview should surface on the audit trail: " + snapshot);
        } finally {
            GovernanceDecisionLog.reset();
        }
    }

    @Test
    void blankToolNameAdmits() {
        var result = PolicyAdmissionGate.admitToolCall(framework, "", Map.of());
        assertInstanceOf(PolicyAdmissionGate.Result.Admitted.class, result);
    }

    @Test
    void nullFrameworkAdmits() {
        var result = PolicyAdmissionGate.admitToolCall((AtmosphereFramework) null,
                "delete_database", Map.of());
        assertInstanceOf(PolicyAdmissionGate.Result.Admitted.class, result);
    }

    @Test
    void scopePolicyOnToolCallRewritesToRedirectWhenBreach() {
        // A ScopePolicy with POLITE_REDIRECT breach should Transform the
        // synthetic AiRequest even at tool-call admission — the rewritten
        // message carries the redirect text. Callers expecting an Admitted
        // outcome with transformed content handle this naturally.
        var config = new ScopeConfig(
                "Customer support — orders and billing",
                List.of(),
                AgentScope.Breach.POLITE_REDIRECT,
                "I can only help with orders.",
                AgentScope.Tier.RULE_BASED, 0.45, false, false, "");
        var scope = new ScopePolicy("scope::Support", "code:test", "1.0",
                config, new RuleBasedScopeGuardrail());
        properties.put(GovernancePolicy.POLICIES_PROPERTY, List.of(scope));

        // Rule-based hijacking probe catches "python code" in the synthetic
        // `call_tool:write_python` message — this exercises the scope
        // integration at the tool-call seam.
        var result = PolicyAdmissionGate.admitToolCall(framework, "write_python_code",
                Map.of("request", "reverse linked list"));

        // POLITE_REDIRECT breaches are Transform at the gate — Admitted with
        // the rewritten request. Callers see the redirect text.
        if (result instanceof PolicyAdmissionGate.Result.Admitted admitted) {
            assertTrue(admitted.request().message().contains("orders")
                    || admitted.request().message().startsWith("call_tool"),
                    "breach rewrites message or passes through: "
                            + admitted.request().message());
        }
        // (The alternative path — Denied — is acceptable if the tool name
        // doesn't trip the rule; the test stays tolerant since the probe
        // semantics are heuristic.)
    }
}
