package ai.dynamixs.mcp;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

import jakarta.json.Json;
import jakarta.json.JsonObject;
import jakarta.json.JsonObjectBuilder;
import jakarta.json.JsonString;

/**
 * Represents an MCP Resource based on Imixs-Workflow BPMN models.
 * 
 * MCP Resources represent entities that can be read by the MCP client. Each
 * resource corresponds to a workflow task/event combination.
 */
public class MCPResource implements Serializable {

    private static final long serialVersionUID = 1L;

    // MCP Standard Fields
    private String uri;                         // Resource URI
    private String name;                        // Human-readable name
    private String description;                 // Resource description
    private String mimeType;                    // MIME type of the resource
    private Map<String, Object> annotations;    // Additional metadata

    // Imixs-specific fields
    private String modelVersion;
    private int taskId;
    private int eventId;

    // Constructors
    public MCPResource() {
        this.annotations = new HashMap<>();
    }

    public MCPResource(String modelVersion, int taskId, int eventId) {
        this();
        this.modelVersion = modelVersion;
        this.taskId = taskId;
        this.eventId = eventId;
        this.uri = createResourceUri(modelVersion, taskId, eventId);
    }

    /**
     * Creates a resource URI from Imixs workflow components
     */
    public static String createResourceUri(String modelVersion, int taskId, int eventId) {
        if (modelVersion == null || modelVersion.trim().isEmpty()) {
            throw new IllegalArgumentException("Model version cannot be null or empty");
        }
        return String.format("imixs://workflow/%s/%d/%d", modelVersion, taskId, eventId);
    }

    /**
     * Parses model version from URI
     */
    public String getModelVersionFromUri() {
        if (uri == null || !uri.startsWith("imixs://workflow/")) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        String path = uri.substring("imixs://workflow/".length());
        String[] parts = path.split("/");
        if (parts.length < 3) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        return parts[0];
    }

    /**
     * Parses task ID from URI
     */
    public int getTaskIdFromUri() {
        if (uri == null || !uri.startsWith("imixs://workflow/")) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        String path = uri.substring("imixs://workflow/".length());
        String[] parts = path.split("/");
        if (parts.length < 3) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        try {
            return Integer.parseInt(parts[1]);
        } catch (NumberFormatException e) {
            throw new IllegalStateException("Invalid task ID in resource URI: " + uri, e);
        }
    }

    /**
     * Parses event ID from URI
     */
    public int getEventIdFromUri() {
        if (uri == null || !uri.startsWith("imixs://workflow/")) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        String path = uri.substring("imixs://workflow/".length());
        String[] parts = path.split("/");
        if (parts.length < 3) {
            throw new IllegalStateException("Invalid resource URI format: " + uri);
        }
        try {
            return Integer.parseInt(parts[2]);
        } catch (NumberFormatException e) {
            throw new IllegalStateException("Invalid event ID in resource URI: " + uri, e);
        }
    }

    /**
     * Converts this resource to MCP JSON format
     */
    public JsonObject toJsonObject() {
        JsonObjectBuilder builder = Json.createObjectBuilder()
                .add("uri", uri != null ? uri : "")
                .add("name", name != null ? name : "")
                .add("description", description != null ? description : "");

        if (mimeType != null) {
            builder.add("mimeType", mimeType);
        }

        // Annotations object
        if (annotations != null && !annotations.isEmpty()) {
            JsonObjectBuilder annotationsBuilder = Json.createObjectBuilder();
            annotations.forEach((key, value) -> {
                if (value instanceof String) {
                    annotationsBuilder.add(key, (String) value);
                } else if (value instanceof Number) {
                    annotationsBuilder.add(key, ((Number) value).doubleValue());
                } else if (value instanceof Boolean) {
                    annotationsBuilder.add(key, (Boolean) value);
                } else if (value != null) {
                    annotationsBuilder.add(key, value.toString());
                }
            });
            builder.add("annotations", annotationsBuilder.build());
        }

        return builder.build();
    }

    /**
     * Creates an MCPResource from a JsonObject
     */
    public static MCPResource fromJsonObject(JsonObject jsonObject) {
        MCPResource resource = new MCPResource();

        resource.setUri(jsonObject.getString("uri", ""));
        resource.setName(jsonObject.getString("name", ""));
        resource.setDescription(jsonObject.getString("description", ""));

        if (jsonObject.containsKey("mimeType")) {
            resource.setMimeType(jsonObject.getString("mimeType"));
        }

        // Annotations
        if (jsonObject.containsKey("annotations")) {
            JsonObject annotationsObject = jsonObject.getJsonObject("annotations");
            Map<String, Object> annotations = new HashMap<>();
            annotationsObject.forEach((key, value) -> {
                switch (value.getValueType()) {
                case STRING:
                    annotations.put(key, ((JsonString) value).getString());
                    break;
                case NUMBER:
                    annotations.put(key, ((jakarta.json.JsonNumber) value).doubleValue());
                    break;
                case TRUE:
                    annotations.put(key, Boolean.TRUE);
                    break;
                case FALSE:
                    annotations.put(key, Boolean.FALSE);
                    break;
                default:
                    annotations.put(key, value.toString());
                }
            });
            resource.setAnnotations(annotations);
        }

        return resource;
    }

    /**
     * Validates this resource for MCP compliance
     */
    public boolean isValid() {
        if (uri == null || uri.trim().isEmpty()) {
            return false;
        }

        if (name == null || name.trim().isEmpty()) {
            return false;
        }

        // Validate URI format
        try {
            getModelVersionFromUri();
            getTaskIdFromUri();
            getEventIdFromUri();
        } catch (Exception e) {
            return false;
        }

        return true;
    }

    // Getters and Setters
    public String getUri() {
        return uri;
    }

    public void setUri(String uri) {
        this.uri = uri;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getMimeType() {
        return mimeType;
    }

    public void setMimeType(String mimeType) {
        this.mimeType = mimeType;
    }

    public Map<String, Object> getAnnotations() {
        return annotations;
    }

    public void setAnnotations(Map<String, Object> annotations) {
        this.annotations = annotations != null ? annotations : new HashMap<>();
    }

    public String getModelVersion() {
        return modelVersion;
    }

    public void setModelVersion(String modelVersion) {
        this.modelVersion = modelVersion;
    }

    public int getTaskId() {
        return taskId;
    }

    public void setTaskId(int taskId) {
        this.taskId = taskId;
    }

    public int getEventId() {
        return eventId;
    }

    public void setEventId(int eventId) {
        this.eventId = eventId;
    }

    // Convenience methods for annotations
    public void addAnnotation(String key, Object value) {
        if (annotations == null) {
            annotations = new HashMap<>();
        }
        annotations.put(key, value);
    }

    public String getAnnotationString(String key) {
        Object value = annotations != null ? annotations.get(key) : null;
        return value != null ? value.toString() : null;
    }

    public Boolean getAnnotationBoolean(String key) {
        Object value = annotations != null ? annotations.get(key) : null;
        if (value instanceof Boolean) {
            return (Boolean) value;
        }
        return null;
    }

    @Override
    public String toString() {
        return String.format("MCPResource{uri='%s', name='%s', modelVersion='%s', taskId=%d, eventId=%d}",
                uri, name, modelVersion, taskId, eventId);
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null || getClass() != obj.getClass())
            return false;
        MCPResource that = (MCPResource) obj;
        return uri != null ? uri.equals(that.uri) : that.uri == null;
    }

    @Override
    public int hashCode() {
        return uri != null ? uri.hashCode() : 0;
    }
}