mcp-ai-agent-guidelines/dist/tools/mermaid/handlers/sequence.handler.js

A comprehensive Model Context Protocol server providing advanced tools, resources, and prompts for implementing AI agent best practices

import { extractAction } from "../utils/helpers.utils.js";
import { BaseDiagramHandler } from "./base.handler.js";
/**
 * Sequence diagram handler.
 * Generates UML sequence diagrams showing interactions between participants.
 */
export class SequenceHandler extends BaseDiagramHandler {
    diagramType = "sequence";
    generate(description, theme, advancedFeatures) {
        const header = ["sequenceDiagram"];
        if (theme)
            header.unshift(`%%{init: {'theme':'${theme}'}}%%`);
        // Parse description to extract participants and interactions
        const { participants, interactions } = this.parseSequenceDescription(description);
        // Add participants
        if (participants.length > 0) {
            for (const p of participants) {
                header.push(`participant ${p.id} as ${p.name}`);
            }
        }
        // Add interactions
        if (interactions.length > 0) {
            for (const interaction of interactions) {
                header.push(interaction);
            }
        }
        else {
            // Fallback to default template if parsing fails
            const body = [
                "participant U as User",
                "participant S as System",
                "participant D as Database",
                "U->>S: Request",
                "S->>D: Query",
                "D-->>S: Data",
                "S-->>U: Response",
            ];
            return [...header, ...body].join("\n");
        }
        // Add advanced features like loops, alt blocks, etc.
        if (advancedFeatures?.autonumber === true) {
            header.splice(1, 0, "autonumber");
        }
        return header.join("\n");
    }
    parseSequenceDescription(description) {
        const participants = [];
        const interactions = [];
        const participantMap = new Map();
        // Extract participant names (nouns that appear frequently or are explicitly mentioned)
        const words = description.toLowerCase().split(/\s+/);
        const commonParticipants = [
            "user",
            "system",
            "server",
            "client",
            "database",
            "api",
            "service",
            "admin",
            "customer",
        ];
        let participantId = 65; // ASCII 'A'
        for (const word of words) {
            const clean = word.replace(/[^a-z]/g, "");
            if (commonParticipants.includes(clean) && !participantMap.has(clean)) {
                const id = String.fromCharCode(participantId++);
                const name = clean.charAt(0).toUpperCase() + clean.slice(1);
                participantMap.set(clean, id);
                participants.push({ id, name });
            }
        }
        // Extract interactions from sentences
        const sentences = description
            .split(/[.!?\n]+/)
            .map((s) => s.trim())
            .filter((s) => s.length > 0);
        for (const sentence of sentences) {
            const lower = sentence.toLowerCase();
            // Look for interaction patterns
            for (const [name1, id1] of participantMap) {
                for (const [name2, id2] of participantMap) {
                    if (name1 !== name2) {
                        // Check for various interaction patterns
                        if (lower.includes(`${name1} sends`) ||
                            lower.includes(`${name1} to ${name2}`)) {
                            const action = extractAction(sentence);
                            interactions.push(`${id1}->>${id2}: ${action}`);
                        }
                        else if (lower.includes(`${name2} responds`) ||
                            lower.includes(`${name2} returns`)) {
                            const action = extractAction(sentence);
                            interactions.push(`${id2}-->>${id1}: ${action}`);
                        }
                    }
                }
            }
        }
        return { participants, interactions };
    }
}
//# sourceMappingURL=sequence.handler.js.map