let
  lib = import <nixpkgs/lib>;
  agentsLib = (import ../../lib {inherit lib;}).agents;

  # Test 1: renderForTool throws for unknown tools
  testUnknownTool = let
    result = builtins.tryEval (
      agentsLib.renderForTool {
        pkgs = {};
        agentsInput = {};
        tool = "unknown-tool";
      }
    );
  in
    assert result.success == false; {result = "pass";};

  # Test 2: loadCanonical extracts loadAgents from input
  testLoadCanonical = let
    fakeInput = {lib.loadAgents = {test = {description = "test";};};};
    result = agentsLib.loadCanonical {agentsInput = fakeInput;};
  in
    assert result == {test = {description = "test";};}; {result = "pass";};

  # Test 3: renderForPi accepts codingRules parameter without error (null case)
  # Verifies that passing codingRules = null produces the same result as omitting it.
  # Uses a minimal fake canonical set instead of a real agents repo.
  testPiNullCodingRules = let
    pkgs = import <nixpkgs> {};
    canonical = {
      chiron = {
        mode = "primary";
        description = "Test primary agent";
        display_name = "Chiron";
        systemPrompt = "You are a test agent.";
        permissions = {};
      };
    };
    result = agentsLib.renderForPi {
      inherit pkgs canonical;
      codingRules = null;
    };
    agentsMd = builtins.readFile "${result}/AGENTS.md";
    hasMarkers = builtins.match ".*CODING-RULES:START.*" agentsMd != null;
  in
    assert hasMarkers == false; {result = "pass";};

  # Test 4: renderForPi with codingRules includes rules in AGENTS.md
  # Uses the real AGENTS repo to read rule files (requires --impure or local path)
  testPiWithCodingRules = let
    agentsPath = /home/sascha.koenig/p/AI/AGENTS;
    pkgs = import <nixpkgs> {};
    canonical = {
      chiron = {
        mode = "primary";
        description = "Test primary agent";
        display_name = "Chiron";
        systemPrompt = "You are a test agent.";
        permissions = {};
      };
    };
    result = agentsLib.renderForPi {
      inherit pkgs canonical;
      codingRules = {
        agents = agentsPath;
        concerns = ["coding-style"];
        languages = [];
        frameworks = [];
      };
    };
    agentsMd = builtins.readFile "${result}/AGENTS.md";
    hasStartMarker = builtins.match ".*CODING-RULES:START.*" agentsMd != null;
    hasEndMarker = builtins.match ".*CODING-RULES:END.*" agentsMd != null;
    hasCodingStyle = builtins.match ".*Coding Style.*" agentsMd != null;
    # Also verify agent descriptions are still present
    hasAgentInstructions = builtins.match ".*Agent Instructions.*" agentsMd != null;
  in
    assert hasStartMarker == true;
    assert hasEndMarker == true;
    assert hasCodingStyle == true;
    assert hasAgentInstructions == true; {result = "pass";};
in {
  unknown-tool-throws = testUnknownTool;
  load-canonical = testLoadCanonical;
  pi-null-coding-rules = testPiNullCodingRules;
  pi-with-coding-rules = testPiWithCodingRules;
}