import { Type } from "typebox";
import { type Result, err, ok } from "../util/result";
import { defineBrowserTool, type ToolErr, type ToolOk } from "../util/tool";
import { fillDeclaration } from "./fill-engine";
import { detailsOf, resolveAndCall } from "./element-call";

const FILL_FN = fillDeclaration({ rejectSelect: false, focusFirst: true });

const FieldValue = Type.Union([Type.String(), Type.Boolean()], {
  description: "Value to set. String for text inputs / textareas / selects / contenteditable; boolean for checkboxes & radios.",
});

const FillFormArgs = Type.Object({
  fields: Type.Array(
    Type.Object({
      ref: Type.String({ description: "Stable element ref from browser_snapshot (e.g. 'e7')." }),
      value: FieldValue,
    }),
    { minItems: 1, description: "Fields to fill in one batch, each by ref." },
  ),
});

export const fillFormTool = defineBrowserTool({
  name: "browser_fill_form",
  label: "Browser Fill Form",
  description:
    "Fill multiple form fields in one call — the efficient way to complete a form. Each field is { ref, value }; refs come from browser_snapshot's [eN]. Handles text inputs, textareas, selects, checkboxes, radios, and contenteditable, drives React/Vue controlled inputs correctly, and reports the resulting value of every field.",
  promptSnippet: "Fill many form fields at once by ref — React-safe, self-confirming",
  promptGuidelines: [
    "Preferred for forms: snapshot once, then fill all fields in a single browser_fill_form call.",
    "The result summarizes how many fields filled cleanly and flags any value mismatches or per-field errors.",
    "Re-run browser_snapshot afterwards to verify the form state if needed.",
  ],
  parameters: FillFormArgs,
  concurrency: "serialized",
  async handler(args, { client }): Promise<Result<ToolOk, ToolErr>> {
    const results: Array<Readonly<Record<string, unknown>>> = [];
    let okCount = 0;
    const issues: string[] = [];
    for (const f of args.fields) {
      const r = await resolveAndCall(client, f.ref, FILL_FN, [f.value]);
      if (!r.success) {
        results.push({ ref: f.ref, ok: false, error: r.error.message });
        issues.push(`ref ${f.ref} (${r.error.message})`);
        continue;
      }
      const res = r.data;
      const wanted = typeof f.value === "boolean" ? undefined : String(f.value);
      const got = res.value !== undefined ? String(res.value) : undefined;
      const mismatch = wanted !== undefined && got !== undefined && got !== wanted && res.text !== wanted;
      const fieldOk = res.ok === true && !mismatch;
      if (fieldOk) okCount++;
      else issues.push(`ref ${f.ref} (${res.ok === false ? (res.reason ?? "failed") : "value mismatch"})`);
      results.push({ ref: f.ref, ok: fieldOk, mismatch, ...detailsOf(f.ref, res) });
    }
    const text =
      `Filled ${okCount}/${args.fields.length} fields` +
      (issues.length > 0 ? `; issues: ${issues.join(", ")}` : "");
    if (okCount === 0) {
      return err({ kind: "invalid_state", message: text, details: { results } });
    }
    return ok({ text, details: { results } });
  },
});