import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
import { keyHint } from "@earendil-works/pi-coding-agent";
import { Text } from "@earendil-works/pi-tui";
import { runCli } from "../cli.ts";
import { TOOLS } from "../schemas.ts";

/**
 * `cbm_list_projects`: same passthrough execute as the generic tools, but with
 * a bespoke TUI renderer. The raw JSON carries per-project metadata, so the
 * renderer collapses it to "N projects" / "none" (expandable to a short list).
 * Node/edge counts only appear with `include_details: true` (0.10.x); the
 * envelope carries `total`/`has_more` for paging. The LLM still sees the full
 * JSON in `content`.
 */

type Project = {
  name?: string;
  root_path?: string;
  branch?: string;
  nodes?: number;
  edges?: number;
};

type ProjectList = { projects?: Project[]; total?: number; has_more?: boolean };

export function registerListProjects(pi: ExtensionAPI) {
  const def = TOOLS.find((t) => t.tool === "list_projects")!;
  pi.registerTool({
    name: "cbm_list_projects",
    label: "cbm:list_projects",
    description: def.description,
    parameters: def.parameters,
    async execute(_toolCallId, params, signal) {
      if (signal?.aborted) {
        return { content: [{ type: "text", text: "Cancelled" }], details: {} };
      }
      const out = await runCli("list_projects", params, signal ?? undefined);
      let parsed: ProjectList | null = null;
      try {
        parsed = JSON.parse(out) as ProjectList;
      } catch {
        /* fall back to raw text below */
      }
      return {
        // LLM still sees the full JSON.
        content: [{ type: "text", text: out || "{}" }],
        // Renderer reads structured fields from details.
        details: parsed ?? { raw: out },
      };
    },
    renderCall(_args, theme) {
      return new Text(theme.fg("toolTitle", theme.bold("cbm:list_projects")), 0, 0);
    },
    renderResult(result, { expanded, isPartial }, theme) {
      if (isPartial) {
        return new Text(theme.fg("warning", "⏳ Listing…"), 0, 0);
      }
      const d = result.details as ProjectList & { raw?: string };
      if (!d || d.raw !== undefined) {
        return new Text(theme.fg("error", `✗ ${d?.raw ?? "list failed"}`), 0, 0);
      }

      const projects = d.projects ?? [];
      const count = d.total ?? projects.length;

      // None indexed → single dim line.
      if (count === 0) {
        return new Text(theme.fg("dim", "∅ no indexed projects"), 0, 0);
      }

      const head =
        theme.fg("success", theme.bold(`✔ ${count} project${count === 1 ? "" : "s"}`)) +
        (d.has_more ? " " + theme.fg("dim", "· more") : "");

      if (!expanded) {
        return new Text(
          head + "  " + theme.fg("dim", `(${keyHint("app.tools.expand", "expand")})`),
          0,
          0,
        );
      }

      const lines: string[] = [head];
      for (const p of projects.slice(0, 20)) {
        const name = theme.fg("accent", p.name ?? "?");
        const stats =
          p.nodes != null
            ? "  " + theme.fg("muted", `${p.nodes} nodes · ${p.edges ?? "?"} edges`)
            : p.root_path
              ? "  " + theme.fg("muted", p.root_path)
              : "";
        lines.push("  " + name + stats);
      }
      if (projects.length > 20) {
        lines.push("  " + theme.fg("dim", `… ${projects.length - 20} more`));
      }
      return new Text(lines.join("\n"), 0, 0);
    },
  });
}