monochange 0.6.2

use std::collections::BTreeSet;
use std::path::Path;
use std::path::PathBuf;

use monochange_config::validate_workspace;
use monochange_core::CliCommandDefinition;
use monochange_core::ReleaseManifest;
use rmcp::ErrorData as McpError;
use rmcp::ServerHandler;
use rmcp::ServiceExt;
use rmcp::handler::server::router::tool::ToolRouter;
use rmcp::handler::server::wrapper::Parameters;
use rmcp::model::*;
use rmcp::schemars;
use rmcp::tool;
use rmcp::tool_handler;
use rmcp::tool_router;
use serde::Deserialize;
use serde::Serialize;
use serde_json::json;

use crate::ChangeBump;
use crate::PreparedRelease;

/// Common `path` parameter used by MCP tools that operate on a repository root.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct PathParam {
	pub path: Option<String>,
}

/// Empty payload for tools that do not need arguments.
#[derive(Debug, Default, Deserialize, schemars::JsonSchema)]
pub struct EmptyParam {}

/// Input payload for the MCP changeset diagnostics tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct DiagnosticsParam {
	pub path: Option<String>,
	#[serde(default)]
	pub changeset: Vec<String>,
}

/// Input payload for the MCP lint explanation tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct LintExplainParam {
	pub id: String,
}

/// Input payload for the MCP change-file creation tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct ChangeParam {
	pub path: Option<String>,
	pub package: Vec<String>,
	pub bump: McpChangeBump,
	pub version: Option<String>,
	pub reason: String,
	#[serde(rename = "type")]
	pub change_type: Option<String>,
	#[serde(default)]
	pub caused_by: Vec<String>,
	pub details: Option<String>,
	pub output: Option<String>,
}

/// Input payload for the MCP changeset-policy evaluation tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct AffectedParam {
	pub path: Option<String>,
	pub changed_paths: Vec<String>,
	#[serde(default)]
	pub labels: Vec<String>,
}

/// Input payload for the MCP analyze-changes tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct AnalyzeChangesParam {
	pub path: Option<String>,
	/// Explicit frame specification (e.g., "working", "main...feature", "pr:target,source")
	pub frame: Option<String>,
	/// Detection level: "basic", "signature", or "semantic"
	pub detection_level: Option<String>,
	/// Maximum number of changeset suggestions to generate
	pub max_suggestions: Option<usize>,
}

/// Input payload for the MCP validate-changeset tool.
#[derive(Debug, Deserialize, schemars::JsonSchema)]
pub struct ValidateChangesetParam {
	pub path: Option<String>,
	/// Path to the changeset file to validate
	pub changeset_path: String,
}

/// Validation issue for a changeset.
#[derive(Debug, Serialize, schemars::JsonSchema)]
#[non_exhaustive]
pub struct ValidationIssue {
	pub severity: String,
	pub message: String,
	pub suggestion: Option<String>,
}

/// Parse a frame string into a `ChangeFrame`.
fn parse_frame(frame_str: &str) -> monochange_analysis::ChangeFrame {
	use monochange_analysis::ChangeFrame;

	if frame_str == "working" || frame_str == "HEAD" {
		return ChangeFrame::WorkingDirectory;
	}

	if frame_str == "staged" {
		return ChangeFrame::StagedOnly;
	}

	// Try parsing as branch range: "main...feature"
	if let Some((base, head)) = frame_str.split_once("...") {
		return ChangeFrame::BranchRange {
			base: base.to_string(),
			head: head.to_string(),
		};
	}

	// Try parsing as PR format: "pr:target,source"
	if let Some(stripped) = frame_str.strip_prefix("pr:")
		&& let Some((target, pr_branch)) = stripped.split_once(',')
	{
		return ChangeFrame::PullRequest {
			target: target.to_string(),
			pr_branch: pr_branch.to_string(),
		};
	}

	// Default to working directory
	ChangeFrame::WorkingDirectory
}

/// Parse a detection level string.
fn parse_detection_level(level: &str) -> monochange_analysis::DetectionLevel {
	use monochange_analysis::DetectionLevel;

	match level.to_lowercase().as_str() {
		"basic" => DetectionLevel::Basic,
		"semantic" => DetectionLevel::Semantic,
		_ => DetectionLevel::Signature, // Default
	}
}

/// Validate changeset content against semantic diff output.
fn validate_changeset_content(
	changeset: &monochange_config::LoadedChangesetFile,
	analysis: &monochange_analysis::ChangeAnalysis,
) -> Vec<ValidationIssue> {
	let mut issues = Vec::new();
	let changeset_text = render_changeset_text(changeset);
	let mentioned_refs = extract_backticked_refs(&changeset_text);
	let mut known_item_refs = BTreeSet::new();
	let mut known_package_refs = BTreeSet::new();
	let mut targeted_package_ids = BTreeSet::new();

	for signal in &changeset.signals {
		targeted_package_ids.insert(signal.package_id.clone());
	}

	for package_id in &targeted_package_ids {
		let Some(package_analysis) = find_package_analysis(analysis, package_id) else {
			issues.push(ValidationIssue {
				severity: "error".to_string(),
				message: format!(
					"changeset targets `{package_id}` but that package has no current diff in the analyzed frame"
				),
				suggestion: Some(
					"remove the stale target, update the changeset to match the current diff, or analyze a different frame".to_string(),
				),
			});
			continue;
		};
		let package_label = &package_analysis.package_id;

		known_package_refs.insert(package_analysis.package_id.clone());
		known_package_refs.insert(package_analysis.package_name.clone());
		known_package_refs.insert(package_analysis.package_record_id.clone());

		let item_refs = semantic_item_refs(package_analysis);
		known_item_refs.extend(item_refs.iter().cloned());

		if package_analysis.semantic_changes.is_empty() {
			issues.push(ValidationIssue {
				severity: "warning".to_string(),
				message: format!(
					"changeset targets `{package_label}` but no semantic changes were detected for that package"
				),
				suggestion: Some(
					"if the change is intentionally internal, review it manually; otherwise update the changeset or the analyzed frame".to_string(),
				),
			});
			continue;
		}

		let mentions_detected_item = mentioned_refs
			.iter()
			.any(|reference| item_refs.contains(reference));
		if !mentioned_refs.is_empty() && mentions_detected_item {
			continue;
		}

		debug_assert!(
			!item_refs.is_empty(),
			"semantic changes should yield at least one item reference"
		);
		let examples = render_semantic_item_examples(item_refs.iter());

		issues.push(ValidationIssue {
			severity: "warning".to_string(),
			message: format!(
				"changeset does not mention any detected semantic item for `{package_label}`"
			),
			suggestion: Some(format!(
				"mention one or more changed items such as {examples}"
			)),
		});
	}

	for reference in mentioned_refs {
		if known_item_refs.contains(&reference) || known_package_refs.contains(&reference) {
			continue;
		}

		issues.push(ValidationIssue {
			severity: "error".to_string(),
			message: format!(
				"changeset references `{reference}` but that item was not found in the current semantic diff"
			),
			suggestion: Some(
				"remove the stale reference or update it to match the current code change"
					.to_string(),
			),
		});
	}

	issues
}

fn find_package_analysis<'a>(
	analysis: &'a monochange_analysis::ChangeAnalysis,
	package_id: &str,
) -> Option<&'a monochange_analysis::PackageChangeAnalysis> {
	analysis
		.package_analyses
		.values()
		.find(|package| package.package_id == package_id || package.package_record_id == package_id)
}

fn render_changeset_text(changeset: &monochange_config::LoadedChangesetFile) -> String {
	let mut text = String::new();
	let mut wrote_part = false;
	if let Some(summary) = &changeset.summary {
		text.push_str(summary);
		wrote_part = true;
	}
	if let Some(details) = &changeset.details {
		if wrote_part {
			text.push_str("\n\n");
		}
		text.push_str(details);
	}
	text
}

fn render_semantic_item_examples<'a>(items: impl IntoIterator<Item = &'a String>) -> String {
	let mut rendered = String::new();
	for (index, item) in items.into_iter().take(3).enumerate() {
		if index > 0 {
			rendered.push_str(", ");
		}
		rendered.push('`');
		rendered.push_str(item);
		rendered.push('`');
	}
	rendered
}

fn extract_backticked_refs(text: &str) -> BTreeSet<String> {
	let mut refs = BTreeSet::new();
	let mut current = String::new();
	let mut inside = false;

	for character in text.chars() {
		if character == '`' {
			if inside && !current.trim().is_empty() {
				refs.insert(current.trim().to_string());
			}
			inside = !inside;
			current.clear();
			continue;
		}

		if inside {
			current.push(character);
		}
	}

	refs
}

fn semantic_item_refs(
	package_analysis: &monochange_analysis::PackageChangeAnalysis,
) -> BTreeSet<String> {
	let mut refs = BTreeSet::new();
	for change in &package_analysis.semantic_changes {
		refs.insert(change.item_path.clone());
		if let Some(last_segment) = change.item_path.rsplit("::").next() {
			refs.insert(last_segment.to_string());
		}
	}
	refs
}

/// Semver bump accepted by the MCP change-file tool.
#[derive(Debug, Clone, Copy, Deserialize, schemars::JsonSchema)]
#[serde(rename_all = "snake_case")]
pub enum McpChangeBump {
	None,
	Patch,
	Minor,
	Major,
}

impl From<McpChangeBump> for ChangeBump {
	fn from(value: McpChangeBump) -> Self {
		match value {
			McpChangeBump::None => Self::None,
			McpChangeBump::Patch => Self::Patch,
			McpChangeBump::Minor => Self::Minor,
			McpChangeBump::Major => Self::Major,
		}
	}
}

/// Stdio MCP server exposing structured `monochange` tools.
#[derive(Debug, Clone)]
pub struct MonochangeMcpServer {
	#[allow(dead_code)]
	tool_router: ToolRouter<Self>,
}

#[tool_handler]
impl ServerHandler for MonochangeMcpServer {
	fn get_info(&self) -> ServerInfo {
		let mut info = ServerInfo::default();
		info.instructions = Some(
			"monochange manages versions and releases across Cargo, npm, Deno, and Dart/Flutter \
			 workspaces. Prefer validation and dry-run planning before mutating release state. \
			 Read monochange.toml first, inspect the normalized model with discover, use change \
			 to write explicit .changeset files, and use release preview or release manifest \
			 tools before source-provider publishing."
				.into(),
		);
		info.capabilities = ServerCapabilities::builder().enable_tools().build();
		info
	}
}

fn resolve_root(path: Option<&str>) -> PathBuf {
	let Some(path_str) = path else {
		return std::env::current_dir().unwrap_or_else(|_| PathBuf::from("."));
	};

	PathBuf::from(path_str)
}

fn json_result(value: serde_json::Value) -> CallToolResult {
	let text = serde_json::to_string_pretty(&value)
		.unwrap_or_else(|_| "{\"ok\":false,\"summary\":\"failed to serialize\"}".to_string());
	let mut result = CallToolResult::success(vec![Content::text(text)]);
	result.structured_content = Some(value);
	result
}

fn json_error_result(value: serde_json::Value) -> CallToolResult {
	let text = serde_json::to_string_pretty(&value)
		.unwrap_or_else(|_| "{\"ok\":false,\"summary\":\"failed to serialize\"}".to_string());
	let mut result = CallToolResult::error(vec![Content::text(text)]);
	result.structured_content = Some(value);
	result
}

fn manifest_for_prepared_release(prepared_release: &PreparedRelease) -> ReleaseManifest {
	let cli_command = CliCommandDefinition {
		name: "release-manifest".to_string(),
		help_text: Some("Render a release manifest for MCP consumers".to_string()),
		inputs: Vec::new(),
		steps: Vec::new(),
		dry_run: false,
	};
	super::build_release_manifest(&cli_command, prepared_release, &[])
}

fn prepared_release_value(prepared_release: &PreparedRelease) -> serde_json::Value {
	json!({
		"dry_run": prepared_release.dry_run,
		"version": prepared_release.version,
		"group_version": prepared_release.group_version,
		"released_packages": prepared_release.released_packages,
		"release_targets": prepared_release.release_targets,
		"changed_files": prepared_release.changed_files,
		"updated_changelogs": prepared_release.updated_changelogs,
		"deleted_changesets": prepared_release.deleted_changesets,
		"changesets": prepared_release.changesets,
		"plan": prepared_release.plan,
	})
}

#[tool_router]
impl MonochangeMcpServer {
	/// Construct a server with the default tool router.
	pub fn new() -> Self {
		Self {
			tool_router: Self::tool_router(),
		}
	}

	#[tool(
		name = "monochange_validate",
		description = "Validate monochange.toml and .changeset targets for a repository."
	)]
	async fn validate(
		&self,
		Parameters(params): Parameters<PathParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		if let Err(error) = validate_workspace(&root) {
			return Ok(json_error_result(json!({
				"ok": false,
				"action": "validate",
				"root": root,
				"summary": error.render(),
				"error": error.render()
			})));
		}

		Ok(json_result(json!({
			"ok": true,
			"action": "validate",
			"root": root,
			"summary": "workspace validation passed"
		})))
	}

	#[tool(
		name = "monochange_discover",
		description = "Discover packages, dependencies, and groups across the repository."
	)]
	async fn discover(
		&self,
		Parameters(params): Parameters<PathParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		let report = match crate::discover_workspace(&root) {
			Ok(report) => report,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "discover",
					"root": root,
					"summary": error.render(),
					"error": error.render()
				})));
			}
		};

		Ok(json_result(json!({
			"ok": true,
			"action": "discover",
			"summary": format!(
				"Discovered {} package(s) and {} dependency edge(s).",
				report.packages.len(),
				report.dependencies.len()
			),
			"report": report,
		})))
	}

	#[tool(
		name = "monochange_diagnostics",
		description = "Inspect pending changesets with git and review context as structured JSON."
	)]
	async fn diagnostics(
		&self,
		Parameters(params): Parameters<DiagnosticsParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		let report = match crate::changesets::diagnose_changesets(&root, &params.changeset).await {
			Ok(report) => report,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "diagnostics",
					"root": root,
					"summary": error.render(),
					"error": error.render()
				})));
			}
		};

		Ok(json_result(json!({
			"ok": true,
			"action": "diagnostics",
			"summary": format!(
				"Loaded {} changeset diagnostic record(s).",
				report.changesets.len()
			),
			"report": report,
		})))
	}

	#[tool(
		name = "monochange_change",
		description = "Write a .changeset markdown file for one or more package or group ids."
	)]
	async fn change(
		&self,
		Parameters(params): Parameters<ChangeParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());
		let output = params.output.as_deref().map(Path::new);
		let bump = ChangeBump::from(params.bump);

		let request = crate::AddChangeFileRequest::builder()
			.package_refs(&params.package)
			.bump(bump.into())
			.reason(&params.reason)
			.version(params.version.as_deref())
			.change_type(params.change_type.as_deref())
			.caused_by(&params.caused_by)
			.details(params.details.as_deref())
			.output(output)
			.build();

		let path = match crate::add_change_file(&root, request) {
			Ok(path) => path,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "change",
					"root": root,
					"summary": error.render(),
					"error": error.render()
				})));
			}
		};

		Ok(json_result(json!({
			"ok": true,
			"action": "change",
			"root": root,
			"path": path,
			"summary": format!("Wrote change file {}", path.display())
		})))
	}

	#[tool(
		name = "monochange_release_preview",
		description = "Prepare a dry-run release preview from discovered .changeset files."
	)]
	async fn release_preview(
		&self,
		Parameters(params): Parameters<PathParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		let prepared_release = match crate::prepare_release(&root, true).await {
			Ok(release) => release,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "release_preview",
					"root": root,
					"summary": error.render(),
					"error": error.render()
				})));
			}
		};

		Ok(json_result(json!({
			"ok": true,
			"action": "release_preview",
			"summary": format!(
				"Prepared dry-run release preview with {} release target(s).",
				prepared_release.release_targets.len()
			),
			"release": prepared_release_value(&prepared_release)
		})))
	}

	#[tool(
		name = "monochange_release_manifest",
		description = "Generate a dry-run release manifest JSON document for downstream automation."
	)]
	async fn release_manifest(
		&self,
		Parameters(params): Parameters<PathParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		let prepared_release = match crate::prepare_release(&root, true).await {
			Ok(release) => release,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "release_manifest",
					"root": root,
					"summary": error.render(),
					"error": error.render()
				})));
			}
		};

		let manifest = manifest_for_prepared_release(&prepared_release);

		Ok(json_result(json!({
			"ok": true,
			"action": "release_manifest",
			"summary": format!(
				"Generated dry-run release manifest with {} release target(s).",
				manifest.release_targets.len()
			),
			"manifest": manifest,
		})))
	}

	#[tool(
		name = "monochange_affected_packages",
		description = "Evaluate changeset policy from changed paths and optional labels."
	)]
	async fn affected_packages(
		&self,
		Parameters(params): Parameters<AffectedParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());

		let evaluation =
			match crate::affected_packages(&root, &params.changed_paths, &params.labels).await {
				Ok(eval) => eval,
				Err(error) => {
					return Ok(json_error_result(json!({
						"ok": false,
						"action": "affected_packages",
						"root": root,
						"summary": error.render(),
						"error": error.render()
					})));
				}
			};

		Ok(json_result(json!({
			"ok": evaluation.status != monochange_core::ChangesetPolicyStatus::Failed,
			"action": "affected_packages",
			"summary": evaluation.summary,
			"evaluation": evaluation,
		})))
	}

	#[tool(
		name = "monochange_lint_catalog",
		description = "List registered manifest lint rules and presets as structured JSON."
	)]
	async fn lint_catalog(
		&self,
		Parameters(_params): Parameters<EmptyParam>,
	) -> Result<CallToolResult, McpError> {
		let rules = crate::lint::available_lint_rules();
		let presets = crate::lint::available_lint_presets();

		Ok(json_result(json!({
			"ok": true,
			"action": "lint_catalog",
			"summary": format!(
				"Loaded {} lint rule(s) and {} preset(s).",
				rules.len(),
				presets.len()
			),
			"rules": rules,
			"presets": presets,
		})))
	}

	#[tool(
		name = "monochange_lint_explain",
		description = "Explain one manifest lint rule or preset as structured JSON."
	)]
	async fn lint_explain(
		&self,
		Parameters(params): Parameters<LintExplainParam>,
	) -> Result<CallToolResult, McpError> {
		if let Some(rule) = crate::lint::explain_lint_rule(&params.id) {
			return Ok(json_result(json!({
				"ok": true,
				"action": "lint_explain",
				"kind": "rule",
				"summary": format!("Loaded lint rule `{}`.", rule.id),
				"entry": rule,
			})));
		}

		if let Some(preset) = crate::lint::explain_lint_preset(&params.id) {
			return Ok(json_result(json!({
				"ok": true,
				"action": "lint_explain",
				"kind": "preset",
				"summary": format!("Loaded lint preset `{}`.", preset.id),
				"entry": preset,
			})));
		}

		Ok(json_error_result(json!({
			"ok": false,
			"action": "lint_explain",
			"summary": format!("Unknown lint rule or preset `{}`.", params.id),
			"error": format!("unknown lint rule or preset `{}`", params.id)
		})))
	}

	#[tool(
		name = "monochange_analyze_changes",
		description = "Analyze git diff and return ecosystem-specific semantic diffs for changed packages."
	)]
	async fn analyze_changes(
		&self,
		Parameters(params): Parameters<AnalyzeChangesParam>,
	) -> Result<CallToolResult, McpError> {
		use monochange_analysis::AnalysisConfig;
		use monochange_analysis::ChangeFrame;

		let root = resolve_root(params.path.as_deref());

		// Determine the change frame
		let frame = match params.frame {
			Some(frame_str) => parse_frame(&frame_str),
			None => {
				match ChangeFrame::detect(&root) {
					Ok(f) => f,
					Err(e) => {
						return Ok(json_error_result(json!({
							"ok": false,
							"action": "analyze_changes",
							"root": root,
							"summary": format!("Failed to detect change frame: {}", e),
							"error": e.to_string()
						})));
					}
				}
			}
		};

		// Configure analysis
		// Configure analysis
		let detection_level = params.detection_level.as_deref().map(parse_detection_level);
		let config = AnalysisConfig {
			detection_level: detection_level.unwrap_or_else(|| {
				use monochange_analysis::DetectionLevel;
				DetectionLevel::Signature
			}),
			thresholds: monochange_analysis::GroupingThresholds::default(),
			max_suggestions: params.max_suggestions.unwrap_or(10),
		};

		// Run analysis
		let analysis = match monochange_analysis::analyze_changes(&root, &frame, &config) {
			Ok(a) => a,
			Err(e) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "analyze_changes",
					"root": root,
					"summary": format!("Analysis failed: {}", e.render()),
					"error": e.render()
				})));
			}
		};

		// Convert to JSON
		let analysis_json = serde_json::to_value(&analysis)
			.map_err(|e| McpError::internal_error(e.to_string(), None))?;

		let package_count = analysis.package_analyses.len();
		let semantic_change_count = analysis
			.package_analyses
			.values()
			.map(|package| package.semantic_changes.len())
			.sum::<usize>();

		Ok(json_result(json!({
			"ok": true,
			"action": "analyze_changes",
			"frame": frame.to_string(),
			"analysis": analysis_json,
			"summary": format!(
				"Analyzed {} package(s) and found {} semantic change(s)",
				package_count,
				semantic_change_count,
			)
		})))
	}

	#[tool(
		name = "monochange_validate_changeset",
		description = "Validate that a changeset matches the current semantic diff for its targeted packages."
	)]
	async fn validate_changeset(
		&self,
		Parameters(params): Parameters<ValidateChangesetParam>,
	) -> Result<CallToolResult, McpError> {
		let root = resolve_root(params.path.as_deref());
		let changeset_path = root.join(&params.changeset_path);

		// Load the changeset
		let configuration = match monochange_config::load_workspace_configuration(&root) {
			Ok(c) => c,
			Err(e) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "validate_changeset",
					"root": root,
					"summary": format!("Failed to load workspace: {}", e.render()),
					"error": e.render()
				})));
			}
		};

		let discovery = match crate::discover_workspace(&root) {
			Ok(d) => d,
			Err(e) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "validate_changeset",
					"root": root,
					"summary": format!("Failed to discover workspace: {}", e.render()),
					"error": e.render()
				})));
			}
		};

		let loaded = match monochange_config::load_changeset_file(
			&changeset_path,
			&configuration,
			&discovery.packages,
		) {
			Ok(l) => l,
			Err(e) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "validate_changeset",
					"root": root,
					"changeset_path": changeset_path,
					"summary": format!("Failed to load changeset: {}", e.render()),
					"error": e.render()
				})));
			}
		};

		let frame = match monochange_analysis::ChangeFrame::detect(&root) {
			Ok(frame) => frame,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "validate_changeset",
					"root": root,
					"changeset_path": changeset_path,
					"summary": format!("Failed to detect change frame: {error}"),
					"error": error.to_string()
				})));
			}
		};

		let analysis = match monochange_analysis::analyze_changes(
			&root,
			&frame,
			&monochange_analysis::AnalysisConfig::default(),
		) {
			Ok(analysis) => analysis,
			Err(error) => {
				return Ok(json_error_result(json!({
					"ok": false,
					"action": "validate_changeset",
					"root": root,
					"changeset_path": changeset_path,
					"summary": format!("Semantic analysis failed: {}", error.render()),
					"error": error.render()
				})));
			}
		};

		let issues = validate_changeset_content(&loaded, &analysis);
		let valid = issues.is_empty();
		let lifecycle_status = if issues.iter().any(|issue| issue.severity == "error") {
			"stale"
		} else if issues.is_empty() {
			"current"
		} else {
			"incomplete"
		};

		Ok(json_result(json!({
			"ok": valid,
			"action": "validate_changeset",
			"frame": frame.to_string(),
			"changeset_path": params.changeset_path,
			"valid": valid,
			"issues": issues,
			"lifecycle_status": lifecycle_status,
			"summary": if valid {
				"Changeset validation passed".to_string()
			} else {
				format!("Found {} validation issue(s)", issues.len())
			}
		})))
	}
}

/// Run the stdio MCP server used by `mc mcp`.
pub async fn run_server() {
	let server = MonochangeMcpServer::new();
	let transport = rmcp::transport::io::stdio();

	let running = match server.serve(transport).await {
		Ok(running) => running,
		Err(error) => {
			eprintln!("monochange-mcp: failed to start server: {error}");
			return;
		}
	};

	let _ = running.waiting().await;
}

#[allow(clippy::disallowed_methods)]
#[cfg(test)]
#[path = "__tests__/mcp_tests.rs"]
mod tests;