"use strict";

import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
import { Type } from "typebox";
import { StringEnum } from "@earendil-works/pi-ai";
import { getConfig } from "../config";
import { processImage } from "../media";
import { visionCompletion } from "../client";
import { DIAGRAM_UNDERSTANDING } from "../prompts";
import {
  DEFAULT_MAX_BYTES,
  DEFAULT_MAX_LINES,
  truncateHead,
} from "@earendil-works/pi-coding-agent";

export function registerUnderstandDiagramTool(pi: ExtensionAPI) {
  pi.registerTool({
    name: "understand_technical_diagram",
    label: "Understand Diagram",
    description:
      "Analyze system architecture diagrams, UML class/sequence diagrams, flowcharts, ER diagrams, and network diagrams. Provides structured component breakdowns, relationship mappings, design pattern analysis, and potential issues identification. Supports local files (png, jpg) and HTTP(S) URLs.",
    promptSnippet: "Analyze architecture diagrams, UML, flowcharts, ER diagrams — structured interpretation",
    promptGuidelines: [
      "Use understand_technical_diagram when the user provides a technical diagram (architecture, UML, ER, flowchart, network) and wants it explained. Use the optional diagramType hint ('uml_class', 'sequence', 'flowchart', 'er', 'architecture', 'network', 'component') for better accuracy.",
    ],
    parameters: Type.Object({
      imagePath: Type.String({
        description:
          "Path to the diagram image (relative to cwd, supports @ prefix) or HTTP(S) URL.",
      }),
      prompt: Type.Optional(
        Type.String({
          description:
            "What should the AI explain about this diagram? Defaults to a comprehensive analysis.",
        })
      ),
      diagramType: Type.Optional(
        StringEnum([
          "uml_class",
          "sequence",
          "flowchart",
          "er",
          "architecture",
          "network",
          "component",
        ] as const)
      ),
    }),
    async execute(_toolCallId, params, signal, onUpdate, ctx) {
      const config = getConfig();

      onUpdate?.({
        content: [{ type: "text", text: "正在调用 GLM-4.6V 解读图表..." }],
      });

      const image = processImage(params.imagePath, ctx.cwd, config.maxImageSizeMB);

      let userPrompt =
        params.prompt || "Explain this diagram comprehensively, covering its structure, components, relationships, and design patterns.";
      if (params.diagramType) {
        userPrompt = `Diagram type: ${params.diagramType}\n\n${userPrompt}`;
      }

      const result = await visionCompletion(
        config,
        DIAGRAM_UNDERSTANDING,
        [image],
        userPrompt,
        signal
      );

      const truncated = truncateHead(result, {
        maxLines: DEFAULT_MAX_LINES,
        maxBytes: DEFAULT_MAX_BYTES,
      });

      let text = truncated.content;
      if (truncated.truncated) {
        text += `\n\n[输出已截断: ${truncated.outputLines}/${truncated.totalLines} 行]`;
      }

      return {
        content: [{ type: "text", text }],
        details: { raw: result },
      };
    },
  });
}