barbacane_compiler/spec_parser/

parser.rs

use std::collections::{BTreeMap, HashSet};

use serde_json::Value;

use super::error::ParseError;
use super::model::{
    ApiSpec, ContentSchema, DispatchConfig, Message, MiddlewareConfig, Operation, Parameter,
    RequestBody, ResponseContent, SpecFormat,
};

/// Resolve a JSON Reference like `#/components/schemas/User` from the spec root.
///
/// Only local references (`#/...`) are supported. Returns `None` for external refs.
fn resolve_ref<'a>(root: &'a Value, ref_path: &str) -> Option<&'a Value> {
    if !ref_path.starts_with("#/") {
        return None;
    }
    let mut current = root;
    for segment in ref_path[2..].split('/') {
        let unescaped = segment.replace("~1", "/").replace("~0", "~");
        current = current.get(&unescaped)?;
    }
    Some(current)
}

/// Recursively resolve all `$ref` pointers in a JSON Schema value.
///
/// Inlines the referenced definition in place. `visited` tracks the current resolution
/// chain to detect circular references.
fn resolve_schema_refs(
    value: &Value,
    root: &Value,
    visited: &mut HashSet<String>,
) -> Result<Value, ParseError> {
    match value {
        Value::Object(obj) => {
            if let Some(ref_str) = obj.get("$ref").and_then(|v| v.as_str()) {
                if !visited.insert(ref_str.to_string()) {
                    return Err(ParseError::SchemaError(format!(
                        "circular $ref detected: {}",
                        ref_str
                    )));
                }
                let target = resolve_ref(root, ref_str)
                    .ok_or_else(|| ParseError::UnresolvedRef(ref_str.to_string()))?;
                let resolved = resolve_schema_refs(target, root, visited)?;
                visited.remove(ref_str);
                Ok(resolved)
            } else {
                let mut new_obj = serde_json::Map::with_capacity(obj.len());
                for (key, val) in obj {
                    new_obj.insert(key.clone(), resolve_schema_refs(val, root, visited)?);
                }
                Ok(Value::Object(new_obj))
            }
        }
        Value::Array(arr) => {
            let items: Result<Vec<_>, _> = arr
                .iter()
                .map(|v| resolve_schema_refs(v, root, visited))
                .collect();
            Ok(Value::Array(items?))
        }
        other => Ok(other.clone()),
    }
}

/// HTTP methods we recognize in OpenAPI paths.
/// Includes `query` from OpenAPI 3.2 (RFC 9110 extension).
const HTTP_METHODS: &[&str] = &[
    "get", "post", "put", "delete", "patch", "head", "options", "trace", "query",
];

/// Parse an OpenAPI or AsyncAPI spec from a YAML/JSON string.
pub fn parse_spec(input: &str) -> Result<ApiSpec, ParseError> {
    // Parse YAML (also handles JSON since JSON is valid YAML)
    let root: Value =
        serde_yaml::from_str(input).map_err(|e| ParseError::ParseError(e.to_string()))?;

    let root_obj = root
        .as_object()
        .ok_or_else(|| ParseError::ParseError("spec root must be an object".into()))?;

    // Detect format
    let (format, version) = detect_format(root_obj)?;

    // Extract info
    let info = root_obj
        .get("info")
        .and_then(|v| v.as_object())
        .ok_or_else(|| ParseError::SchemaError("missing 'info' object".into()))?;

    let title = info
        .get("title")
        .and_then(|v| v.as_str())
        .ok_or_else(|| ParseError::SchemaError("missing 'info.title'".into()))?
        .to_string();

    let api_version = info
        .get("version")
        .and_then(|v| v.as_str())
        .unwrap_or("0.0.0")
        .to_string();

    // Extract root-level x-barbacane-* extensions
    let extensions = extract_extensions(root_obj);

    // Extract global middlewares
    let global_middlewares = extract_middlewares(root_obj);

    // Parse operations based on format
    let operations = match format {
        SpecFormat::OpenApi => parse_openapi_paths(root_obj, &root)?,
        SpecFormat::AsyncApi => parse_asyncapi_channels(root_obj, &root)?,
    };

    Ok(ApiSpec {
        filename: None,
        format,
        version,
        title,
        api_version,
        operations,
        global_middlewares,
        extensions,
    })
}

/// Parse a spec from a file path.
pub fn parse_spec_file(path: &std::path::Path) -> Result<ApiSpec, ParseError> {
    let content = std::fs::read_to_string(path)?;
    let mut spec = parse_spec(&content)?;
    spec.filename = path
        .file_name()
        .and_then(|s| s.to_str())
        .map(|s| s.to_string());
    Ok(spec)
}

/// Detect whether this is OpenAPI or AsyncAPI and extract the version.
fn detect_format(
    root: &serde_json::Map<String, Value>,
) -> Result<(SpecFormat, String), ParseError> {
    if let Some(version) = root.get("openapi").and_then(|v| v.as_str()) {
        if !version.starts_with("3.") {
            return Err(ParseError::SchemaError(format!(
                "unsupported OpenAPI version: {} (only 3.x supported)",
                version
            )));
        }
        Ok((SpecFormat::OpenApi, version.to_string()))
    } else if let Some(version) = root.get("asyncapi").and_then(|v| v.as_str()) {
        if !version.starts_with("3.") {
            return Err(ParseError::SchemaError(format!(
                "unsupported AsyncAPI version: {} (only 3.x supported)",
                version
            )));
        }
        Ok((SpecFormat::AsyncApi, version.to_string()))
    } else {
        Err(ParseError::UnknownFormat)
    }
}

/// Extract all x-barbacane-* keys from an object.
fn extract_extensions(obj: &serde_json::Map<String, Value>) -> BTreeMap<String, Value> {
    obj.iter()
        .filter(|(k, _)| k.starts_with("x-barbacane-"))
        .map(|(k, v)| (k.clone(), v.clone()))
        .collect()
}

/// Extract x-barbacane-middlewares from an object.
fn extract_middlewares(obj: &serde_json::Map<String, Value>) -> Vec<MiddlewareConfig> {
    obj.get("x-barbacane-middlewares")
        .and_then(|v| v.as_array())
        .map(|arr| {
            arr.iter()
                .filter_map(|item| serde_json::from_value(item.clone()).ok())
                .collect()
        })
        .unwrap_or_default()
}

/// Extract x-barbacane-dispatch from an operation object.
fn extract_dispatch(obj: &serde_json::Map<String, Value>) -> Option<DispatchConfig> {
    obj.get("x-barbacane-dispatch")
        .and_then(|v| serde_json::from_value(v.clone()).ok())
}

/// Parse OpenAPI 3.x paths into operations.
fn parse_openapi_paths(
    root: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Vec<Operation>, ParseError> {
    let mut operations = Vec::new();

    let paths = match root.get("paths").and_then(|v| v.as_object()) {
        Some(p) => p,
        None => return Ok(operations), // No paths is valid (empty API)
    };

    for (path, path_item) in paths {
        let path_obj = path_item.as_object().ok_or_else(|| {
            ParseError::SchemaError(format!("path item for '{}' must be an object", path))
        })?;

        // Path-level parameters (inherited by all operations)
        let path_params = parse_parameters(path_obj, spec_root)?;

        for method in HTTP_METHODS {
            if let Some(op_value) = path_obj.get(*method) {
                let op_obj = op_value.as_object().ok_or_else(|| {
                    ParseError::SchemaError(format!(
                        "operation {} {} must be an object",
                        method.to_uppercase(),
                        path
                    ))
                })?;

                // Merge path-level and operation-level parameters
                let mut params = path_params.clone();
                params.extend(parse_parameters(op_obj, spec_root)?);

                let operation_id = op_obj
                    .get("operationId")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let summary = op_obj
                    .get("summary")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let description = op_obj
                    .get("description")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let request_body = parse_request_body(op_obj, spec_root)?;
                let responses = parse_responses(op_obj, spec_root)?;

                let dispatch = extract_dispatch(op_obj);

                let middlewares = if op_obj.contains_key("x-barbacane-middlewares") {
                    Some(extract_middlewares(op_obj))
                } else {
                    None
                };

                // Extract deprecated flag (standard OpenAPI field)
                let deprecated = op_obj
                    .get("deprecated")
                    .and_then(|v| v.as_bool())
                    .unwrap_or(false);

                // Extract sunset date from x-sunset extension (RFC 8594)
                let sunset = op_obj
                    .get("x-sunset")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let extensions = extract_extensions(op_obj);

                operations.push(Operation {
                    path: path.clone(),
                    method: method.to_uppercase(),
                    operation_id,
                    summary,
                    description,
                    parameters: params,
                    request_body,
                    dispatch,
                    middlewares,
                    deprecated,
                    sunset,
                    extensions,
                    messages: Vec::new(), // OpenAPI doesn't use AsyncAPI messages
                    bindings: BTreeMap::new(), // OpenAPI doesn't use protocol bindings
                    responses,
                });
            }
        }

        // OpenAPI 3.2: parse additionalOperations (custom HTTP methods)
        if let Some(additional) = path_obj
            .get("additionalOperations")
            .and_then(|v| v.as_object())
        {
            for (method_name, op_value) in additional {
                let op_obj = op_value.as_object().ok_or_else(|| {
                    ParseError::SchemaError(format!(
                        "additionalOperations.{} on {} must be an object",
                        method_name, path
                    ))
                })?;

                let mut params = path_params.clone();
                params.extend(parse_parameters(op_obj, spec_root)?);

                let operation_id = op_obj
                    .get("operationId")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let summary = op_obj
                    .get("summary")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let description = op_obj
                    .get("description")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let request_body = parse_request_body(op_obj, spec_root)?;
                let responses = parse_responses(op_obj, spec_root)?;
                let dispatch = extract_dispatch(op_obj);

                let middlewares = if op_obj.contains_key("x-barbacane-middlewares") {
                    Some(extract_middlewares(op_obj))
                } else {
                    None
                };

                let deprecated = op_obj
                    .get("deprecated")
                    .and_then(|v| v.as_bool())
                    .unwrap_or(false);

                let sunset = op_obj
                    .get("x-sunset")
                    .and_then(|v| v.as_str())
                    .map(|s| s.to_string());

                let extensions = extract_extensions(op_obj);

                operations.push(Operation {
                    path: path.clone(),
                    method: method_name.to_uppercase(),
                    operation_id,
                    summary,
                    description,
                    parameters: params,
                    request_body,
                    dispatch,
                    middlewares,
                    deprecated,
                    sunset,
                    extensions,
                    messages: Vec::new(),
                    bindings: BTreeMap::new(),
                    responses,
                });
            }
        }
    }

    Ok(operations)
}

/// Parse parameters from a path item or operation object.
///
/// OpenAPI 3.2: `in: querystring` parameters use `content` instead of `schema`.
/// The schema is extracted from `content.<media-type>.schema`.
fn parse_parameters(
    obj: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Vec<Parameter>, ParseError> {
    let Some(arr) = obj.get("parameters").and_then(|v| v.as_array()) else {
        return Ok(Vec::new());
    };

    let mut params = Vec::with_capacity(arr.len());
    for item in arr {
        let Some(param_obj) = item.as_object() else {
            continue;
        };
        let Some(location) = param_obj.get("in").and_then(|v| v.as_str()) else {
            continue;
        };
        let location = location.to_string();

        // OpenAPI 3.2: querystring params use content instead of schema
        let raw_schema = if location == "querystring" {
            extract_content_schema(param_obj)
        } else {
            param_obj.get("schema").cloned()
        };

        let schema = raw_schema
            .map(|s| resolve_schema_refs(&s, spec_root, &mut HashSet::new()))
            .transpose()?;

        let Some(name) = param_obj.get("name").and_then(|v| v.as_str()) else {
            continue;
        };
        params.push(Parameter {
            name: name.to_string(),
            location,
            required: param_obj
                .get("required")
                .and_then(|v| v.as_bool())
                .unwrap_or(false),
            schema,
        });
    }
    Ok(params)
}

/// Extract schema from a parameter's `content` map (first media type entry).
///
/// Used for `in: querystring` parameters where the schema lives under
/// `content.<media-type>.schema` instead of the top-level `schema` field.
fn extract_content_schema(param_obj: &serde_json::Map<String, Value>) -> Option<Value> {
    let content = param_obj.get("content")?.as_object()?;
    // Use the first (and typically only) media type entry
    let (_media_type, media_obj) = content.iter().next()?;
    media_obj.as_object()?.get("schema").cloned()
}

/// Parse request body from an operation object.
fn parse_request_body(
    obj: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Option<RequestBody>, ParseError> {
    let Some(body) = obj.get("requestBody").and_then(|v| v.as_object()) else {
        return Ok(None);
    };

    let required = body
        .get("required")
        .and_then(|v| v.as_bool())
        .unwrap_or(false);

    let Some(content_obj) = body.get("content").and_then(|v| v.as_object()) else {
        return Ok(None);
    };

    let mut content = BTreeMap::new();
    for (media_type, media_obj) in content_obj {
        let raw_schema = media_obj.as_object().and_then(|o| o.get("schema").cloned());
        let schema = raw_schema
            .map(|s| resolve_schema_refs(&s, spec_root, &mut HashSet::new()))
            .transpose()?;
        content.insert(media_type.clone(), ContentSchema { schema });
    }

    Ok(Some(RequestBody { required, content }))
}

/// Parse response definitions from an operation object.
fn parse_responses(
    obj: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<BTreeMap<String, ResponseContent>, ParseError> {
    let Some(responses) = obj.get("responses").and_then(|v| v.as_object()) else {
        return Ok(BTreeMap::new());
    };

    let mut result = BTreeMap::new();
    for (status_code, resp_value) in responses {
        // Resolve $ref on the response object itself
        let resolved = resolve_schema_refs(resp_value, spec_root, &mut HashSet::new())?;
        let Some(resp_obj) = resolved.as_object() else {
            continue;
        };

        let Some(content_obj) = resp_obj.get("content").and_then(|v| v.as_object()) else {
            continue;
        };

        let mut content = BTreeMap::new();
        for (media_type, media_obj) in content_obj {
            let raw_schema = media_obj.as_object().and_then(|o| o.get("schema").cloned());
            let schema = raw_schema
                .map(|s| resolve_schema_refs(&s, spec_root, &mut HashSet::new()))
                .transpose()?;
            content.insert(media_type.clone(), ContentSchema { schema });
        }

        if !content.is_empty() {
            result.insert(status_code.clone(), ResponseContent { content });
        }
    }
    Ok(result)
}

/// Parse AsyncAPI 3.x channels and operations.
///
/// AsyncAPI 3.x structure:
/// - `channels`: Map of channel names to channel definitions (address, messages)
/// - `operations`: Map of operation IDs to operation definitions (action, channel ref)
fn parse_asyncapi_channels(
    root: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Vec<Operation>, ParseError> {
    let mut operations = Vec::new();

    // Parse channels first to build a lookup map
    let channels = root.get("channels").and_then(|v| v.as_object());
    let ops = root.get("operations").and_then(|v| v.as_object());

    // If no operations defined, return empty
    let ops = match ops {
        Some(o) => o,
        None => return Ok(operations),
    };

    // Build channel lookup: channel_name -> (address, messages, parameters, bindings)
    let channel_lookup = build_channel_lookup(channels, spec_root)?;

    for (op_id, op_value) in ops {
        let op_obj = op_value.as_object().ok_or_else(|| {
            ParseError::SchemaError(format!("operation '{}' must be an object", op_id))
        })?;

        // Extract action (send/receive)
        let action = op_obj
            .get("action")
            .and_then(|v| v.as_str())
            .ok_or_else(|| {
                ParseError::SchemaError(format!("operation '{}' missing 'action' field", op_id))
            })?;

        // Normalize action to uppercase for consistency with HTTP methods
        let method = match action {
            "send" => "SEND",
            "receive" => "RECEIVE",
            other => {
                return Err(ParseError::SchemaError(format!(
                    "operation '{}' has invalid action '{}' (must be 'send' or 'receive')",
                    op_id, other
                )))
            }
        }
        .to_string();

        // Resolve channel reference
        let (address, channel_messages, channel_params, channel_bindings) =
            resolve_channel_ref(op_obj, &channel_lookup, spec_root)?;

        // Parse operation-level messages (may override or filter channel messages)
        let messages = parse_operation_messages(op_obj, &channel_messages, spec_root)?;

        // For SEND operations, create a request body from the first message payload
        let request_body = if method == "SEND" && !messages.is_empty() {
            messages.first().and_then(|msg| {
                msg.payload.as_ref().map(|schema| {
                    let content_type = msg
                        .content_type
                        .clone()
                        .unwrap_or_else(|| "application/json".to_string());
                    let mut content = BTreeMap::new();
                    content.insert(
                        content_type,
                        ContentSchema {
                            schema: Some(schema.clone()),
                        },
                    );
                    RequestBody {
                        required: true,
                        content,
                    }
                })
            })
        } else {
            None
        };

        // Merge channel and operation-level bindings
        let mut bindings = channel_bindings;
        if let Some(op_bindings) = op_obj.get("bindings").and_then(|v| v.as_object()) {
            for (protocol, config) in op_bindings {
                bindings.insert(protocol.clone(), config.clone());
            }
        }

        // Extract dispatch config
        let dispatch = extract_dispatch(op_obj);

        // Extract middlewares
        let middlewares = if op_obj.contains_key("x-barbacane-middlewares") {
            Some(extract_middlewares(op_obj))
        } else {
            None
        };

        // Extract deprecated and sunset
        let deprecated = op_obj
            .get("deprecated")
            .and_then(|v| v.as_bool())
            .unwrap_or(false);

        let sunset = op_obj
            .get("x-sunset")
            .and_then(|v| v.as_str())
            .map(|s| s.to_string());

        let extensions = extract_extensions(op_obj);

        operations.push(Operation {
            path: address,
            method,
            operation_id: Some(op_id.clone()),
            summary: None,
            description: None,
            parameters: channel_params,
            request_body,
            dispatch,
            middlewares,
            deprecated,
            sunset,
            extensions,
            messages,
            bindings,
            responses: BTreeMap::new(),
        });
    }

    Ok(operations)
}

/// Channel info: (address, messages, parameters, bindings).
type ChannelInfo = (
    String,
    Vec<Message>,
    Vec<Parameter>,
    BTreeMap<String, Value>,
);

/// Build a lookup map of channel names to their definitions.
fn build_channel_lookup(
    channels: Option<&serde_json::Map<String, Value>>,
    spec_root: &Value,
) -> Result<BTreeMap<String, ChannelInfo>, ParseError> {
    let mut lookup = BTreeMap::new();

    let channels = match channels {
        Some(c) => c,
        None => return Ok(lookup),
    };

    for (name, channel_value) in channels {
        let channel_obj = match channel_value.as_object() {
            Some(o) => o,
            None => continue,
        };

        // Extract address (defaults to channel name if not specified)
        let address = channel_obj
            .get("address")
            .and_then(|v| v.as_str())
            .map(|s| s.to_string())
            .unwrap_or_else(|| name.clone());

        // Parse messages
        let messages = parse_channel_messages(channel_obj, spec_root)?;

        // Parse parameters
        let parameters = parse_channel_parameters(channel_obj, spec_root)?;

        // Parse bindings
        let bindings = channel_obj
            .get("bindings")
            .and_then(|v| v.as_object())
            .map(|b| {
                b.iter()
                    .map(|(k, v)| (k.clone(), v.clone()))
                    .collect::<BTreeMap<_, _>>()
            })
            .unwrap_or_default();

        lookup.insert(name.clone(), (address, messages, parameters, bindings));
    }

    Ok(lookup)
}

/// Parse messages from a channel definition.
fn parse_channel_messages(
    channel: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Vec<Message>, ParseError> {
    let messages_obj = match channel.get("messages").and_then(|v| v.as_object()) {
        Some(m) => m,
        None => return Ok(Vec::new()),
    };

    let mut messages = Vec::with_capacity(messages_obj.len());
    for (name, msg_value) in messages_obj {
        let Some(msg_obj) = msg_value.as_object() else {
            continue;
        };

        let payload = msg_obj
            .get("payload")
            .map(|p| resolve_schema_refs(p, spec_root, &mut HashSet::new()))
            .transpose()?;

        let content_type = msg_obj
            .get("contentType")
            .and_then(|v| v.as_str())
            .map(|s| s.to_string());

        let bindings = msg_obj
            .get("bindings")
            .and_then(|v| v.as_object())
            .map(|b| {
                b.iter()
                    .map(|(k, v)| (k.clone(), v.clone()))
                    .collect::<BTreeMap<_, _>>()
            })
            .unwrap_or_default();

        messages.push(Message {
            name: name.clone(),
            payload,
            content_type,
            bindings,
        });
    }
    Ok(messages)
}

/// Parse parameters from a channel definition (for templated addresses).
fn parse_channel_parameters(
    channel: &serde_json::Map<String, Value>,
    spec_root: &Value,
) -> Result<Vec<Parameter>, ParseError> {
    let params = match channel.get("parameters").and_then(|v| v.as_object()) {
        Some(p) => p,
        None => return Ok(Vec::new()),
    };

    let mut result = Vec::with_capacity(params.len());
    for (name, param_value) in params {
        let raw_schema = param_value
            .as_object()
            .and_then(|o| o.get("schema").cloned());
        let schema = raw_schema
            .map(|s| resolve_schema_refs(&s, spec_root, &mut HashSet::new()))
            .transpose()?;

        // In AsyncAPI, channel parameters are always required
        result.push(Parameter {
            name: name.clone(),
            location: "path".to_string(),
            required: true,
            schema,
        });
    }
    Ok(result)
}

/// Resolve a channel reference from an operation.
fn resolve_channel_ref(
    op: &serde_json::Map<String, Value>,
    lookup: &BTreeMap<String, ChannelInfo>,
    spec_root: &Value,
) -> Result<ChannelInfo, ParseError> {
    let channel = op
        .get("channel")
        .ok_or_else(|| ParseError::SchemaError("operation missing 'channel' field".into()))?;

    // Channel can be a $ref or inline
    if let Some(channel_obj) = channel.as_object() {
        if let Some(ref_str) = channel_obj.get("$ref").and_then(|v| v.as_str()) {
            // Parse $ref like "#/channels/userSignedUp"
            let channel_name = ref_str.strip_prefix("#/channels/").ok_or_else(|| {
                ParseError::SchemaError(format!(
                    "invalid channel $ref '{}' (expected #/channels/...)",
                    ref_str
                ))
            })?;

            lookup.get(channel_name).cloned().ok_or_else(|| {
                ParseError::SchemaError(format!(
                    "channel '{}' referenced but not defined",
                    channel_name
                ))
            })
        } else {
            // Inline channel definition
            let address = channel_obj
                .get("address")
                .and_then(|v| v.as_str())
                .map(|s| s.to_string())
                .unwrap_or_default();

            let messages = parse_channel_messages(channel_obj, spec_root)?;
            let parameters = parse_channel_parameters(channel_obj, spec_root)?;
            let bindings = channel_obj
                .get("bindings")
                .and_then(|v| v.as_object())
                .map(|b| {
                    b.iter()
                        .map(|(k, v)| (k.clone(), v.clone()))
                        .collect::<BTreeMap<_, _>>()
                })
                .unwrap_or_default();

            Ok((address, messages, parameters, bindings))
        }
    } else {
        Err(ParseError::SchemaError(
            "operation 'channel' must be an object (either $ref or inline)".into(),
        ))
    }
}

/// Parse messages from an operation (may reference channel messages via $ref).
fn parse_operation_messages(
    op: &serde_json::Map<String, Value>,
    channel_messages: &[Message],
    spec_root: &Value,
) -> Result<Vec<Message>, ParseError> {
    // If operation has explicit messages array, use those
    let Some(msgs) = op.get("messages").and_then(|v| v.as_array()) else {
        // Use all channel messages (already resolved)
        return Ok(channel_messages.to_vec());
    };

    let mut result = Vec::with_capacity(msgs.len());
    for msg in msgs {
        let Some(obj) = msg.as_object() else {
            continue;
        };

        if let Some(ref_str) = obj.get("$ref").and_then(|v| v.as_str()) {
            // Reference to channel message
            // Format: "#/channels/channelName/messages/messageName"
            let parts: Vec<&str> = ref_str.split('/').collect();
            if parts.len() >= 5 && parts[3] == "messages" {
                let msg_name = parts[4];
                if let Some(m) = channel_messages.iter().find(|m| m.name == msg_name) {
                    result.push(m.clone());
                }
            }
            continue;
        }

        // Inline message definition
        let name = obj
            .get("name")
            .and_then(|v| v.as_str())
            .unwrap_or("default")
            .to_string();
        let payload = obj
            .get("payload")
            .map(|p| resolve_schema_refs(p, spec_root, &mut HashSet::new()))
            .transpose()?;
        let content_type = obj
            .get("contentType")
            .and_then(|v| v.as_str())
            .map(|s| s.to_string());
        let bindings = obj
            .get("bindings")
            .and_then(|v| v.as_object())
            .map(|b| {
                b.iter()
                    .map(|(k, v)| (k.clone(), v.clone()))
                    .collect::<BTreeMap<_, _>>()
            })
            .unwrap_or_default();

        result.push(Message {
            name,
            payload,
            content_type,
            bindings,
        });
    }
    Ok(result)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn parse_minimal_openapi() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /health:
    get:
      operationId: getHealth
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.format, SpecFormat::OpenApi);
        assert_eq!(spec.version, "3.1.0");
        assert_eq!(spec.title, "Test API");
        assert_eq!(spec.operations.len(), 1);

        let op = &spec.operations[0];
        assert_eq!(op.path, "/health");
        assert_eq!(op.method, "GET");
        assert_eq!(op.operation_id, Some("getHealth".to_string()));

        let dispatch = op.dispatch.as_ref().unwrap();
        assert_eq!(dispatch.name, "mock");
    }

    #[test]
    fn parse_path_with_parameters() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /users/{id}:
    get:
      operationId: getUser
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: integer
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];
        assert_eq!(op.parameters.len(), 1);

        let param = &op.parameters[0];
        assert_eq!(param.name, "id");
        assert_eq!(param.location, "path");
        assert!(param.required);
    }

    #[test]
    fn parse_global_middlewares() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
x-barbacane-middlewares:
  - name: rate-limit
    config:
      quota: 100
      window: 60
paths:
  /health:
    get:
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.global_middlewares.len(), 1);
        assert_eq!(spec.global_middlewares[0].name, "rate-limit");
    }

    #[test]
    fn parse_operation_middlewares_override() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
x-barbacane-middlewares:
  - name: global-auth
paths:
  /public:
    get:
      x-barbacane-middlewares: []
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];
        // Operation has explicit middlewares (empty array = disable all)
        assert!(op.middlewares.is_some());
        assert_eq!(op.middlewares.as_ref().unwrap().len(), 0);
    }

    #[test]
    fn reject_openapi_2() {
        let yaml = r#"
swagger: "2.0"
info:
  title: Old API
  version: "1.0.0"
paths: {}
"#;
        let result = parse_spec(yaml);
        assert!(matches!(result, Err(ParseError::UnknownFormat)));
    }

    #[test]
    fn parse_multiple_methods() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /users:
    get:
      x-barbacane-dispatch:
        name: mock
    post:
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.operations.len(), 2);

        let methods: Vec<&str> = spec
            .operations
            .iter()
            .map(|op| op.method.as_str())
            .collect();
        assert!(methods.contains(&"GET"));
        assert!(methods.contains(&"POST"));
    }

    #[test]
    fn extract_barbacane_extensions() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
x-barbacane-middlewares:
  - name: rate-limit
    config:
      requests_per_second: 100
paths:
  /health:
    get:
      x-barbacane-dispatch:
        name: mock
      x-barbacane-middlewares:
        - name: cache
          config:
            ttl: 60
"#;
        let spec = parse_spec(yaml).unwrap();
        assert!(spec.extensions.contains_key("x-barbacane-middlewares"));

        let op = &spec.operations[0];
        assert!(op.extensions.contains_key("x-barbacane-middlewares"));
    }

    #[test]
    fn parse_request_body() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /users:
    post:
      operationId: createUser
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - name
              properties:
                name:
                  type: string
                email:
                  type: string
                  format: email
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];

        let body = op.request_body.as_ref().expect("should have request body");
        assert!(body.required);
        assert!(body.content.contains_key("application/json"));

        let json_content = &body.content["application/json"];
        let schema = json_content.schema.as_ref().expect("should have schema");
        assert_eq!(schema.get("type").and_then(|v| v.as_str()), Some("object"));
    }

    #[test]
    fn parse_deprecated_operation() {
        let yaml = r#"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /old-endpoint:
    get:
      deprecated: true
      x-sunset: "Sat, 31 Dec 2025 23:59:59 GMT"
      x-barbacane-dispatch:
        name: mock
  /new-endpoint:
    get:
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.operations.len(), 2);

        // Check deprecated operation
        let old_op = spec
            .operations
            .iter()
            .find(|op| op.path == "/old-endpoint")
            .unwrap();
        assert!(old_op.deprecated);
        assert_eq!(
            old_op.sunset,
            Some("Sat, 31 Dec 2025 23:59:59 GMT".to_string())
        );

        // Check non-deprecated operation
        let new_op = spec
            .operations
            .iter()
            .find(|op| op.path == "/new-endpoint")
            .unwrap();
        assert!(!new_op.deprecated);
        assert!(new_op.sunset.is_none());
    }

    // ==================== AsyncAPI 3.x Tests ====================

    #[test]
    fn parse_minimal_asyncapi() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: User Events API
  version: "1.0.0"
channels:
  userSignedUp:
    address: user/signedup
    messages:
      UserSignedUpMessage:
        payload:
          type: object
          properties:
            userId:
              type: string
operations:
  processUserSignup:
    action: receive
    channel:
      $ref: '#/channels/userSignedUp'
    x-barbacane-dispatch:
      name: kafka
      config:
        topic: user-events
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.format, SpecFormat::AsyncApi);
        assert_eq!(spec.version, "3.0.0");
        assert_eq!(spec.title, "User Events API");
        assert_eq!(spec.operations.len(), 1);

        let op = &spec.operations[0];
        assert_eq!(op.path, "user/signedup");
        assert_eq!(op.method, "RECEIVE");
        assert_eq!(op.operation_id, Some("processUserSignup".to_string()));

        // Check dispatch config
        let dispatch = op.dispatch.as_ref().unwrap();
        assert_eq!(dispatch.name, "kafka");

        // Check messages
        assert_eq!(op.messages.len(), 1);
        assert_eq!(op.messages[0].name, "UserSignedUpMessage");
        assert!(op.messages[0].payload.is_some());
    }

    #[test]
    fn parse_asyncapi_send_operation() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: Notification Service
  version: "1.0.0"
channels:
  notifications:
    address: notifications/{userId}
    parameters:
      userId:
        schema:
          type: string
    messages:
      NotificationMessage:
        contentType: application/json
        payload:
          type: object
          required:
            - title
            - body
          properties:
            title:
              type: string
            body:
              type: string
operations:
  sendNotification:
    action: send
    channel:
      $ref: '#/channels/notifications'
    x-barbacane-dispatch:
      name: nats
      config:
        subject: notifications
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];

        assert_eq!(op.method, "SEND");
        assert_eq!(op.path, "notifications/{userId}");
        assert_eq!(op.operation_id, Some("sendNotification".to_string()));

        // Check channel parameters
        assert_eq!(op.parameters.len(), 1);
        assert_eq!(op.parameters[0].name, "userId");
        assert_eq!(op.parameters[0].location, "path");
        assert!(op.parameters[0].required);

        // SEND operations should have request_body from message payload
        assert!(op.request_body.is_some());
        let body = op.request_body.as_ref().unwrap();
        assert!(body.required);
        assert!(body.content.contains_key("application/json"));

        // Check messages
        assert_eq!(op.messages.len(), 1);
        assert_eq!(
            op.messages[0].content_type,
            Some("application/json".to_string())
        );
    }

    #[test]
    fn parse_asyncapi_with_bindings() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: Order Events
  version: "1.0.0"
channels:
  orderCreated:
    address: orders.created
    bindings:
      kafka:
        topic: order-events
        partitions: 10
        replicas: 3
    messages:
      OrderCreatedMessage:
        bindings:
          kafka:
            key:
              type: string
        payload:
          type: object
operations:
  handleOrderCreated:
    action: receive
    channel:
      $ref: '#/channels/orderCreated'
    bindings:
      kafka:
        groupId: order-processor
    x-barbacane-dispatch:
      name: kafka
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];

        // Check operation-level bindings (merged from channel and operation)
        assert!(op.bindings.contains_key("kafka"));
        let kafka_binding = op.bindings.get("kafka").unwrap();
        // Operation binding should override channel binding
        assert!(kafka_binding.get("groupId").is_some());

        // Check message bindings
        assert!(op.messages[0].bindings.contains_key("kafka"));
    }

    #[test]
    fn parse_asyncapi_inline_channel() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: Inline Channel Test
  version: "1.0.0"
operations:
  inlineOp:
    action: receive
    channel:
      address: inline/topic
      messages:
        InlineMessage:
          payload:
            type: string
    x-barbacane-dispatch:
      name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];

        assert_eq!(op.path, "inline/topic");
        assert_eq!(op.messages.len(), 1);
        assert_eq!(op.messages[0].name, "InlineMessage");
    }

    #[test]
    fn parse_asyncapi_multiple_operations() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: Multi-Op API
  version: "1.0.0"
channels:
  events:
    address: events
    messages:
      Event:
        payload:
          type: object
operations:
  publishEvent:
    action: send
    channel:
      $ref: '#/channels/events'
    x-barbacane-dispatch:
      name: kafka
  consumeEvent:
    action: receive
    channel:
      $ref: '#/channels/events'
    x-barbacane-dispatch:
      name: kafka
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.operations.len(), 2);

        let send_op = spec
            .operations
            .iter()
            .find(|op| op.method == "SEND")
            .unwrap();
        let recv_op = spec
            .operations
            .iter()
            .find(|op| op.method == "RECEIVE")
            .unwrap();

        assert_eq!(send_op.operation_id, Some("publishEvent".to_string()));
        assert_eq!(recv_op.operation_id, Some("consumeEvent".to_string()));
    }

    #[test]
    fn parse_asyncapi_global_middlewares() {
        let yaml = r#"
asyncapi: "3.0.0"
info:
  title: Middleware Test
  version: "1.0.0"
x-barbacane-middlewares:
  - name: auth
    config:
      type: jwt
channels:
  events:
    address: events
    messages:
      Event:
        payload:
          type: object
operations:
  handleEvent:
    action: receive
    channel:
      $ref: '#/channels/events'
    x-barbacane-dispatch:
      name: kafka
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.global_middlewares.len(), 1);
        assert_eq!(spec.global_middlewares[0].name, "auth");
    }

    #[test]
    fn parse_asyncapi_3_1() {
        let yaml = r#"
asyncapi: "3.1.0"
info:
  title: User Events API
  version: "1.0.0"
channels:
  userSignedUp:
    address: user/signedup
    messages:
      UserSignedUpMessage:
        payload:
          type: object
          properties:
            userId:
              type: string
operations:
  processUserSignup:
    action: send
    channel:
      $ref: '#/channels/userSignedUp'
    x-barbacane-dispatch:
      name: kafka
      config:
        topic: user-events
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.format, SpecFormat::AsyncApi);
        assert_eq!(spec.version, "3.1.0");
        assert_eq!(spec.operations.len(), 1);
    }

    #[test]
    fn reject_asyncapi_2() {
        let yaml = r#"
asyncapi: "2.6.0"
info:
  title: Old AsyncAPI
  version: "1.0.0"
channels: {}
"#;
        let result = parse_spec(yaml);
        assert!(matches!(result, Err(ParseError::SchemaError(_))));
    }

    // ==================== OpenAPI 3.2 Tests ====================

    #[test]
    fn parse_query_method() {
        let yaml = r#"
openapi: "3.2.0"
info:
  title: Query Method API
  version: "1.0.0"
paths:
  /search:
    query:
      operationId: searchItems
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                filter:
                  type: string
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.version, "3.2.0");
        assert_eq!(spec.operations.len(), 1);

        let op = &spec.operations[0];
        assert_eq!(op.path, "/search");
        assert_eq!(op.method, "QUERY");
        assert_eq!(op.operation_id, Some("searchItems".to_string()));
        assert!(op.request_body.is_some());
    }

    #[test]
    fn parse_additional_operations() {
        let yaml = r#"
openapi: "3.2.0"
info:
  title: Custom Methods API
  version: "1.0.0"
paths:
  /cache/{key}:
    get:
      operationId: getCache
      x-barbacane-dispatch:
        name: mock
    additionalOperations:
      purge:
        operationId: purgeCache
        parameters:
          - name: key
            in: path
            required: true
            schema:
              type: string
        x-barbacane-dispatch:
          name: mock
          config:
            status: 204
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.operations.len(), 2);

        let get_op = spec
            .operations
            .iter()
            .find(|op| op.method == "GET")
            .unwrap();
        assert_eq!(get_op.operation_id, Some("getCache".to_string()));

        let purge_op = spec
            .operations
            .iter()
            .find(|op| op.method == "PURGE")
            .unwrap();
        assert_eq!(purge_op.operation_id, Some("purgeCache".to_string()));
        assert_eq!(purge_op.parameters.len(), 1);
        assert_eq!(purge_op.parameters[0].name, "key");
    }

    #[test]
    fn parse_additional_operations_inherits_path_params() {
        let yaml = r#"
openapi: "3.2.0"
info:
  title: Path Params Inheritance
  version: "1.0.0"
paths:
  /items/{id}:
    parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
    additionalOperations:
      link:
        operationId: linkItem
        x-barbacane-dispatch:
          name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        assert_eq!(spec.operations.len(), 1);

        let op = &spec.operations[0];
        assert_eq!(op.method, "LINK");
        // Path-level parameters should be inherited
        assert_eq!(op.parameters.len(), 1);
        assert_eq!(op.parameters[0].name, "id");
    }

    #[test]
    fn parse_querystring_parameter() {
        let yaml = r#"
openapi: "3.2.0"
info:
  title: Querystring API
  version: "1.0.0"
paths:
  /search:
    get:
      operationId: search
      parameters:
        - name: q
          in: querystring
          required: true
          content:
            application/x-www-form-urlencoded:
              schema:
                type: string
                minLength: 1
      x-barbacane-dispatch:
        name: mock
"#;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];
        assert_eq!(op.parameters.len(), 1);

        let param = &op.parameters[0];
        assert_eq!(param.name, "q");
        assert_eq!(param.location, "querystring");
        assert!(param.required);
        // Schema should be extracted from content, not top-level schema
        assert!(param.schema.is_some());
        assert_eq!(
            param.schema.as_ref().unwrap().get("type").unwrap(),
            "string"
        );
    }

    // ── $ref resolution tests ────────────────────────────────────────────

    #[test]
    fn resolve_ref_in_parameter_schema() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
components:
  schemas:
    UserId:
      type: integer
      format: int64
paths:
  /users/{id}:
    get:
      parameters:
        - name: id
          in: path
          required: true
          schema:
            $ref: "#/components/schemas/UserId"
      x-barbacane-dispatch:
        name: mock
"##;
        let spec = parse_spec(yaml).unwrap();
        let param = &spec.operations[0].parameters[0];
        let schema = param.schema.as_ref().unwrap();
        // $ref should be inlined — no $ref key, actual schema fields present
        assert!(schema.get("$ref").is_none());
        assert_eq!(schema.get("type").unwrap(), "integer");
        assert_eq!(schema.get("format").unwrap(), "int64");
    }

    #[test]
    fn resolve_ref_in_request_body() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
components:
  schemas:
    CreateUser:
      type: object
      required: [name]
      properties:
        name:
          type: string
paths:
  /users:
    post:
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/CreateUser"
      x-barbacane-dispatch:
        name: mock
"##;
        let spec = parse_spec(yaml).unwrap();
        let body = spec.operations[0].request_body.as_ref().unwrap();
        let schema = body.content["application/json"].schema.as_ref().unwrap();
        assert!(schema.get("$ref").is_none());
        assert_eq!(schema.get("type").unwrap(), "object");
        assert!(schema.get("properties").is_some());
    }

    #[test]
    fn resolve_nested_ref() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
components:
  schemas:
    Address:
      type: object
      properties:
        street:
          type: string
    User:
      type: object
      properties:
        address:
          $ref: "#/components/schemas/Address"
paths:
  /users:
    post:
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/User"
      x-barbacane-dispatch:
        name: mock
"##;
        let spec = parse_spec(yaml).unwrap();
        let body = spec.operations[0].request_body.as_ref().unwrap();
        let schema = body.content["application/json"].schema.as_ref().unwrap();
        assert!(schema.get("$ref").is_none());
        // Nested $ref inside User.properties.address should also be resolved
        let address_schema = schema.get("properties").unwrap().get("address").unwrap();
        assert!(address_schema.get("$ref").is_none());
        assert_eq!(address_schema.get("type").unwrap(), "object");
    }

    #[test]
    fn unresolved_ref_returns_error() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
paths:
  /users:
    get:
      parameters:
        - name: id
          in: query
          schema:
            $ref: "#/components/schemas/DoesNotExist"
      x-barbacane-dispatch:
        name: mock
"##;
        let err = parse_spec(yaml).unwrap_err();
        assert!(
            matches!(err, ParseError::UnresolvedRef(ref s) if s.contains("DoesNotExist")),
            "expected UnresolvedRef, got: {:?}",
            err
        );
    }

    #[test]
    fn circular_ref_returns_error() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test API
  version: "1.0.0"
components:
  schemas:
    Node:
      type: object
      properties:
        child:
          $ref: "#/components/schemas/Node"
paths:
  /nodes:
    get:
      parameters:
        - name: root
          in: query
          schema:
            $ref: "#/components/schemas/Node"
      x-barbacane-dispatch:
        name: mock
"##;
        let err = parse_spec(yaml).unwrap_err();
        assert!(
            matches!(err, ParseError::SchemaError(ref s) if s.contains("circular")),
            "expected SchemaError with 'circular', got: {:?}",
            err
        );
    }

    #[test]
    fn asyncapi_message_payload_ref() {
        let yaml = r##"
asyncapi: "3.0.0"
info:
  title: Test API
  version: "1.0.0"
components:
  schemas:
    UserEvent:
      type: object
      properties:
        userId:
          type: string
channels:
  userSignedUp:
    address: user/signedup
    messages:
      userSignedUp:
        payload:
          $ref: "#/components/schemas/UserEvent"
operations:
  onUserSignedUp:
    action: receive
    channel:
      $ref: "#/channels/userSignedUp"
"##;
        let spec = parse_spec(yaml).unwrap();
        let op = &spec.operations[0];
        let msg = &op.messages[0];
        let payload = msg.payload.as_ref().unwrap();
        assert!(payload.get("$ref").is_none());
        assert_eq!(payload.get("type").unwrap(), "object");
    }

    #[test]
    fn parse_summary_and_description() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test
  version: "1.0.0"
paths:
  /orders:
    post:
      operationId: createOrder
      summary: Create a new order
      description: Creates an order with items and shipping address
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
"##;
        let spec = parse_spec(yaml).expect("should parse");
        let op = &spec.operations[0];
        assert_eq!(op.summary.as_deref(), Some("Create a new order"));
        assert_eq!(
            op.description.as_deref(),
            Some("Creates an order with items and shipping address")
        );
    }

    #[test]
    fn parse_summary_and_description_absent() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test
  version: "1.0.0"
paths:
  /health:
    get:
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
"##;
        let spec = parse_spec(yaml).expect("should parse");
        let op = &spec.operations[0];
        assert!(op.summary.is_none());
        assert!(op.description.is_none());
    }

    #[test]
    fn parse_responses_with_schema() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test
  version: "1.0.0"
paths:
  /orders:
    post:
      operationId: createOrder
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
      responses:
        "200":
          content:
            application/json:
              schema:
                type: object
                properties:
                  order_id:
                    type: string
        "404":
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    type: string
"##;
        let spec = parse_spec(yaml).expect("should parse");
        let op = &spec.operations[0];
        assert_eq!(op.responses.len(), 2);
        assert!(op.responses.contains_key("200"));
        assert!(op.responses.contains_key("404"));
        let resp_200 = &op.responses["200"];
        let schema = resp_200.content["application/json"]
            .schema
            .as_ref()
            .expect("schema");
        assert!(schema["properties"]["order_id"].is_object());
    }

    #[test]
    fn parse_responses_with_ref() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test
  version: "1.0.0"
components:
  schemas:
    Order:
      type: object
      properties:
        id:
          type: string
paths:
  /orders:
    post:
      operationId: createOrder
      x-barbacane-dispatch:
        name: mock
        config:
          status: 200
      responses:
        "200":
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Order'
"##;
        let spec = parse_spec(yaml).expect("should parse");
        let op = &spec.operations[0];
        let schema = op.responses["200"].content["application/json"]
            .schema
            .as_ref()
            .expect("schema");
        // $ref should be resolved inline
        assert!(schema.get("$ref").is_none());
        assert!(schema["properties"]["id"].is_object());
    }

    #[test]
    fn parse_responses_empty_when_no_content() {
        let yaml = r##"
openapi: "3.1.0"
info:
  title: Test
  version: "1.0.0"
paths:
  /health:
    get:
      x-barbacane-dispatch:
        name: mock
        config:
          status: 204
      responses:
        "204":
          description: No content
"##;
        let spec = parse_spec(yaml).expect("should parse");
        let op = &spec.operations[0];
        assert!(op.responses.is_empty());
    }
}