// SPDX-License-Identifier: AGPL-3.0-only
// Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0

import { isTauri } from "@/lib/api-base";
import { copyToClipboard } from "@/lib/copy-to-clipboard";

export interface FrontendSupportSnapshot {
  status?: string | null;
  error?: string | null;
  currentStepIndex?: number | null;
  progressDetail?: string | null;
  elevationPackages?: string[];
  lastUiLogLines?: string[];
  flow?: string | null;
  updatePhase?: string | null;
  updateProgress?: number | null;
}

export interface CopySupportDiagnosticsResult {
  ok: boolean;
  report: string;
  error?: string;
  source: "tauri" | "frontend-fallback";
}

const FALLBACK_LOG_LINE_LIMIT = 200;

const ANSI_ESCAPE_PATTERN = new RegExp(
  `${String.fromCharCode(27)}(?:[@-Z\\-_]|\\[[0-?]*[ -/]*[@-~])`,
  "g",
);

function stripAnsi(text: string): string {
  return text.replace(ANSI_ESCAPE_PATTERN, "");
}

export function redactDiagnosticsText(text: string): string {
  let redacted = stripAnsi(text);

  redacted = redacted.replace(
    /-----BEGIN [^-]*PRIVATE KEY-----[\s\S]*?-----END [^-]*PRIVATE KEY-----/gi,
    "<redacted-private-key>",
  );
  redacted = redacted.replace(
    /([a-z][a-z0-9+.-]*:\/\/)([^/\s@]+)@/gi,
    "$1<redacted>@",
  );
  redacted = redacted.replace(
    /\b(authorization\s*[:=]\s*)(bearer|basic)\s+[^\s,;]+/gi,
    "$1$2 <redacted>",
  );
  redacted = redacted.replace(/\bhf_[A-Za-z0-9]{20,}\b/g, "hf_<redacted>");
  redacted = redacted.replace(/\bghp_[A-Za-z0-9_]{20,}\b/g, "ghp_<redacted>");
  redacted = redacted.replace(/\bgithub_pat_[A-Za-z0-9_]{20,}\b/g, "github_pat_<redacted>");
  redacted = redacted.replace(/\bsk-[A-Za-z0-9_-]{20,}\b/g, "sk-<redacted>");
  redacted = redacted.replace(
    /\b(cookie|set-cookie)\s*[:=]\s*[^\n\r]+/gi,
    "$1=<redacted>",
  );
  redacted = redacted.replace(
    /(^|[\s;])((?:[A-Z0-9]+_)*(?:TOKEN|KEY|SECRET|PASSWORD)(?:_[A-Z0-9]+)*\s*=\s*)[^\s]+/gi,
    "$1$2<redacted>",
  );

  // Redact Unsloth paths before broader home-directory paths.
  redacted = redacted.replace(
    /(?:\/Users|\/home)\/[^\s/]+\/\.unsloth\/studio/gi,
    "<studio_home>",
  );
  redacted = redacted.replace(
    /[A-Z]:\\Users\\[^\s\\]+\\\.unsloth\\studio/gi,
    "<studio_home>",
  );
  redacted = redacted.replace(/(?:\/Users|\/home)\/[^\s/]+/gi, "$HOME");
  redacted = redacted.replace(/[A-Z]:\\Users\\[^\s\\]+/gi, "%USERPROFILE%");
  redacted = redacted.replace(
    /[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}/gi,
    "<redacted-email>",
  );

  return redacted;
}

function safeLines(lines: string[] | undefined): string[] {
  return (lines ?? [])
    .filter((line): line is string => typeof line === "string")
    .slice(-FALLBACK_LOG_LINE_LIMIT);
}

function buildFrontendFallbackReport(
  snapshot: FrontendSupportSnapshot,
  invokeError: unknown,
): string {
  const lines = safeLines(snapshot.lastUiLogLines);
  const report = [
    "DEGRADED FRONTEND-ONLY DIAGNOSTICS",
    "DEGRADED_FRONTEND_ONLY=true",
    `createdAt=${new Date().toISOString()}`,
    "reason=collect_support_diagnostics invoke failed",
    `invokeError=${String(invokeError)}`,
    `status=${snapshot.status ?? "unavailable"}`,
    `flow=${snapshot.flow ?? "unknown"}`,
    `error=${snapshot.error ?? ""}`,
    `currentStepIndex=${snapshot.currentStepIndex ?? ""}`,
    `progressDetail=${snapshot.progressDetail ?? ""}`,
    `elevationPackages=${(snapshot.elevationPackages ?? []).join(",")}`,
    `updatePhase=${snapshot.updatePhase ?? ""}`,
    `updateProgress=${snapshot.updateProgress ?? ""}`,
    "",
    "lastUiLogLines:",
    ...lines,
    "",
    "redaction=frontend_minimal_js_redaction_applied",
    "collectionWarnings=Rust diagnostics command was unavailable; this fallback contains only bounded UI state/log lines.",
  ].join("\n");

  return redactDiagnosticsText(report);
}

async function collectDiagnosticsReport(
  snapshot: FrontendSupportSnapshot,
): Promise<{ report: string; source: CopySupportDiagnosticsResult["source"] }> {
  if (!isTauri) {
    return {
      report: buildFrontendFallbackReport(snapshot, "not running in Tauri"),
      source: "frontend-fallback",
    };
  }

  try {
    const { invoke } = await import("@tauri-apps/api/core");
    const report = await invoke<string>("collect_support_diagnostics", {
      snapshot,
    });
    return { report, source: "tauri" };
  } catch (error) {
    console.warn("collect_support_diagnostics failed; using frontend-only diagnostics", error);
    return {
      report: buildFrontendFallbackReport(snapshot, error),
      source: "frontend-fallback",
    };
  }
}

async function copyWithTauriClipboard(text: string): Promise<boolean> {
  if (!isTauri) return false;
  try {
    const { writeText } = await import("@tauri-apps/plugin-clipboard-manager");
    await writeText(text);
    return true;
  } catch (error) {
    console.warn("Tauri clipboard-manager writeText failed", error);
    return false;
  }
}

export async function copySupportDiagnostics(
  snapshot: FrontendSupportSnapshot,
): Promise<CopySupportDiagnosticsResult> {
  const { report, source } = await collectDiagnosticsReport(snapshot);

  if (await copyWithTauriClipboard(report)) {
    return { ok: true, report, source };
  }

  if (await copyToClipboard(report)) {
    return { ok: true, report, source };
  }

  return {
    ok: false,
    report,
    source,
    error: "Unable to write diagnostics to the clipboard. Select and copy the text manually.",
  };
}