import { register } from "../engine/registry";
import { RuntimeError, type CapabilityHandler } from "../engine/types";
import { powershell } from "./desktop";
import fs from "node:fs";
import os from "node:os";
import path from "node:path";

interface CvTarget { text: string; cx: number; cy: number }
let paddleOcr: { detect: (image: string) => Promise<{ texts: Array<{ text: string; box?: number[][]; mean?: number }> }> } | null = null;

async function getOcr() {
  if (paddleOcr) return paddleOcr;
  const mod = await import("@gutenye/ocr-node");
  paddleOcr = await mod.default.create();
  return paddleOcr as { detect: (image: string) => Promise<{ texts: Array<{ text: string; box?: number[][]; mean?: number }> }> };
}

function cvTarget(args: Record<string, unknown>, nodeId: string): string {
  for (const key of ["cvSelector", "target", "text"]) {
    const v = String(args[key] ?? "").trim();
    if (v) return v.replace(/^text:/, "").replace(/^图片:/, "");
  }
  throw new RuntimeError("validation_error", "CV 目标为空", { nodeId, componentId: nodeId, recommendation: "填写要在屏幕上查找的目标文本" });
}

async function gdiGrabScreen(imagePath: string): Promise<void> {
  const psScript = [
    // 与点击脚本一致: 先声明 DPI 感知, 否则缩放非 100% 时 Bounds 是逻辑像素, 截屏只覆盖屏幕左上角
    "Add-Type -MemberDefinition '[DllImport(\"user32.dll\")] public static extern bool SetProcessDpiAwarenessContext(IntPtr value);' -Name RpaCvDpi -Namespace RpaCv | Out-Null;",
    "try { [RpaCv.RpaCvDpi]::SetProcessDpiAwarenessContext([IntPtr](-4)) | Out-Null } catch {}",
    "Add-Type -AssemblyName System.Drawing | Out-Null;",
    "Add-Type -AssemblyName System.Windows.Forms | Out-Null;",
    "$b = [System.Windows.Forms.SystemInformation]::VirtualScreen;",
    "$bmp = New-Object System.Drawing.Bitmap($b.Width, $b.Height);",
    "$g = [System.Drawing.Graphics]::FromImage($bmp);",
    "$g.CopyFromScreen($b.X, $b.Y, 0, 0, $b.Size);",
    "$g.Dispose();",
    "$bmp.Save(" + JSON.stringify(imagePath) + ");",
    "$bmp.Dispose();"
  ].join(" ");
  await powershell(psScript, 30000);
}

/** 一次屏幕截图: 图片左上角在虚拟桌面上的绝对 DIP 坐标 + 物理/DIP 缩放比 */
interface ScreenShot { imagePath: string; dipX: number; dipY: number; scale: number }

/** desktopCapturer 逐显示器截屏(每屏原生分辨率), 不可用时回退 GDI 全虚拟桌面单图 */
async function grabScreenAll(baseDir: string): Promise<ScreenShot[]> {
  fs.mkdirSync(baseDir, { recursive: true });
  try {
    const { desktopCapturer, screen } = await import("electron");
    if (desktopCapturer && screen?.getAllDisplays) {
      const shots: ScreenShot[] = [];
      const displays = screen.getAllDisplays();
      for (const display of displays) {
        const scale = display.scaleFactor || 1;
        const sources = await desktopCapturer.getSources({
          types: ["screen"],
          thumbnailSize: { width: Math.round(display.bounds.width * scale), height: Math.round(display.bounds.height * scale) }
        });
        const source = sources.find(item => item.display_id === String(display.id))
          || sources.find(item => item.thumbnail.getSize().width === Math.round(display.bounds.width * scale))
          || sources[0];
        if (!source || source.thumbnail.isEmpty()) continue;
        const imagePath = path.join(baseDir, `rpa-cv-screen-${display.id}-${Date.now()}.png`);
        fs.writeFileSync(imagePath, source.thumbnail.toPNG());
        shots.push({ imagePath, dipX: display.bounds.x, dipY: display.bounds.y, scale });
      }
      if (shots.length) return shots;
    }
  } catch {}
  const imagePath = path.join(baseDir, `rpa-cv-screen-${Date.now()}.png`);
  await gdiGrabScreen(imagePath);
  return [{ imagePath, dipX: 0, dipY: 0, scale: 1 }];
}

interface OcrLine { text: string; box?: number[][]; mean?: number }

/** 搜索区域: 框选生成时含 imagePath(区域截图)+x/y(屏幕绝对 DIP 坐标)+scale(该屏缩放); 也可只给坐标范围 */
interface CvRegion { imagePath?: string; x?: number; y?: number; width?: number; height?: number; scale?: number }

function parseRegionArg(value: unknown): CvRegion | null {
  if (!value) return null;
  if (typeof value === "object") return value as CvRegion;
  const s = String(value).trim();
  if (!s) return null;
  if (s.startsWith("{")) {
    try { return JSON.parse(s) as CvRegion; } catch { return null; }
  }
  if (/\.(png|jpe?g|bmp)$/i.test(s) || fs.existsSync(s)) return { imagePath: s };
  return null;
}

function boxCenter(box: number[][]): { cx: number; cy: number } {
  const xs = box.map(p => p[0]);
  const ys = box.map(p => p[1]);
  return { cx: (Math.min(...xs) + Math.max(...xs)) / 2, cy: (Math.min(...ys) + Math.max(...ys)) / 2 };
}

export async function locateTextOnScreen(
  target: string,
  nodeId: string,
  region?: CvRegion | null
): Promise<{ target: string; text: string; cx: number; cy: number }> {
  const ocr = await getOcr();
  const keyword = target.trim();
  // 命中中心换算为屏幕绝对 DIP 坐标
  let found: { text: string; cx: number; cy: number } | null = null;
  const cleanups: string[] = [];

  if (region?.imagePath && fs.existsSync(region.imagePath)) {
    // 框选截图: OCR 只识别该图; 图内物理坐标 ÷ 该屏缩放 + 框选绝对 DIP 原点
    const scale = Number(region.scale ?? 1) || 1;
    const result = await ocr.detect(region.imagePath);
    const hit = (result.texts ?? []).find(t => t.text && t.text.includes(keyword) && t.box && t.box.length >= 4);
    if (hit?.box) {
      const c = boxCenter(hit.box);
      found = {
        text: hit.text,
        cx: (Number(region.x ?? 0) || 0) + c.cx / scale,
        cy: (Number(region.y ?? 0) || 0) + c.cy / scale
      };
    }
  } else {
    // 全屏查找: 逐显示器截屏识别, 覆盖副屏(含负坐标屏); 命中即停
    const shots = await grabScreenAll(path.join(os.tmpdir(), "rpa-cv-shots"));
    for (const shot of shots) {
      const result = await ocr.detect(shot.imagePath);
      const candidates = (result.texts ?? []).filter(t => t.text && t.text.includes(keyword) && t.box && t.box.length >= 4);
      let hit: OcrLine | undefined = candidates[0];
      // 给了坐标范围(绝对 DIP)时, 过滤中心落在区域内的命中
      if (hit && region?.width && region?.height) {
        const rx = Number(region.x ?? 0) || 0;
        const ry = Number(region.y ?? 0) || 0;
        hit = candidates.find(t => {
          const c = boxCenter(t.box!);
          const dx = shot.dipX + c.cx / shot.scale;
          const dy = shot.dipY + c.cy / shot.scale;
          return dx >= rx && dx <= rx + region.width! && dy >= ry && dy <= ry + region.height!;
        });
      }
      if (hit?.box) {
        const c = boxCenter(hit.box);
        found = { text: hit.text, cx: shot.dipX + c.cx / shot.scale, cy: shot.dipY + c.cy / shot.scale };
        break;
      }
      cleanups.push(shot.imagePath);
    }
    // 成功命中时清理全部截图, 未命中保留全部以便排查
    if (found) for (const p of shots.map(s => s.imagePath)) { try { fs.unlinkSync(p); } catch {} }
  }

  if (!found) {
    throw new RuntimeError("cv_not_found", "屏幕上未找到目标文本：" + keyword + (region?.imagePath ? "（搜索范围: 框选区域）" : ""), {
      nodeId,
      componentId: nodeId,
      recommendation: "确认目标文本在" + (region?.imagePath ? "框选区域内" : "屏幕上(含副屏)") + "可见且清晰"
    });
  }
  for (const p of cleanups) { try { fs.unlinkSync(p); } catch {} }
  return { target: keyword, text: found.text, cx: found.cx, cy: found.cy };
}
function screenUser32(): string {
  return [
    "Add-Type -MemberDefinition '[DllImport(\"user32.dll\")] public static extern bool SetProcessDpiAwarenessContext(IntPtr value); [DllImport(\"user32.dll\")] public static extern bool SetCursorPos(int X, int Y); [DllImport(\"user32.dll\")] public static extern void mouse_event(uint flags, uint dx, uint dy, uint data, UIntPtr extra);' -Name RpaCvInput -Namespace RpaCv | Out-Null;",
    "try { [RpaCv.RpaCvInput]::SetProcessDpiAwarenessContext([IntPtr](-4)) | Out-Null } catch {}"
  ].join("\n");
}

function coordinateScript(x: number, y: number, action: "hover" | "click" | "doubleClick" | "paste", value = ""): string {
  const lines = [
    screenUser32(),
    "if (-not [RpaCv.RpaCvInput]::SetCursorPos(" + x + ", " + y + ")) { throw 'cursor_move_failed' }",
    "Start-Sleep -Milliseconds 100"
  ];
  if (action !== "hover") {
    lines.push(
      "[RpaCv.RpaCvInput]::mouse_event(0x0002,0,0,0,[UIntPtr]::Zero)",
      "Start-Sleep -Milliseconds 40",
      "[RpaCv.RpaCvInput]::mouse_event(0x0004,0,0,0,[UIntPtr]::Zero)"
    );
  }
  if (action === "doubleClick") {
    lines.push(
      "Start-Sleep -Milliseconds 70",
      "[RpaCv.RpaCvInput]::mouse_event(0x0002,0,0,0,[UIntPtr]::Zero)",
      "Start-Sleep -Milliseconds 40",
      "[RpaCv.RpaCvInput]::mouse_event(0x0004,0,0,0,[UIntPtr]::Zero)"
    );
  }
  if (action === "paste") {
    lines.push(
      "Add-Type -AssemblyName System.Windows.Forms",
      "Start-Sleep -Milliseconds 220",
      "$saved = $null",
      "try { $saved = [System.Windows.Forms.Clipboard]::GetText() } catch {}",
      "try { [System.Windows.Forms.Clipboard]::SetText(" + JSON.stringify(value) + ") } catch { throw 'clipboard_failed' }",
      "Start-Sleep -Milliseconds 80",
      "[System.Windows.Forms.SendKeys]::SendWait('^a')",
      "Start-Sleep -Milliseconds 60",
      "[System.Windows.Forms.SendKeys]::SendWait('^v')",
      "Start-Sleep -Milliseconds 280",
      "try { if ($saved) { [System.Windows.Forms.Clipboard]::SetText($saved) } else { [System.Windows.Forms.Clipboard]::Clear() } } catch {}"
    );
  }
  lines.push("Write-Output (@{ ok = $true; x = " + x + "; y = " + y + " } | ConvertTo-Json -Compress)");
  return lines.join("\n");
}

/** DIP → 物理像素(SetCursorPos 在 DPI 感知进程里用物理坐标); 无 Electron API 时按原值(缩放 100% 等价) */
async function toPhysical(x: number, y: number): Promise<{ x: number; y: number }> {
  try {
    const { screen } = await import("electron");
    if (screen && typeof screen.dipToScreenPoint === "function") {
      const p = screen.dipToScreenPoint({ x: Math.round(x), y: Math.round(y) });
      return { x: p.x, y: p.y };
    }
  } catch {}
  return { x: Math.round(x), y: Math.round(y) };
}

async function locateFor(args: Record<string, unknown>, node: { id: string; componentId: string }) {
  const target = cvTarget(args, node.id);
  // 可选搜索区域: 框选生成 {x,y,width,height,imagePath,scale}, 限定 OCR 查找范围
  const region = parseRegionArg(args.searchRegion ?? args.region);
  const located = await locateTextOnScreen(target, node.id, region);
  const offsetX = Number(args.offsetX ?? args.offset_x ?? 0) || 0;
  const offsetY = Number(args.offsetY ?? args.offset_y ?? 0) || 0;
  return { located, x: Math.round(located.cx + offsetX), y: Math.round(located.cy + offsetY) };
}

const getTextGround: CapabilityHandler = async (ctx, node, args) => {
  const target = cvTarget(args, node.id);
  const result = await locateTextOnScreen(target, node.id);
  ctx.log("CV_GetText found: " + result.text, "info", node.id);
  return result.text;
};

const setTextGround: CapabilityHandler = async (ctx, node, args) => {
  const value = String(args.value ?? args.text ?? "");
  if (!value) throw new RuntimeError("validation_error", "CV 文本输入内容为空", { nodeId: node.id, componentId: node.componentId });
  const { x, y } = await locateFor(args, node);
  const phys = await toPhysical(x, y);
  await powershell(coordinateScript(phys.x, phys.y, "paste", value), 30000);
  ctx.log("CV_SetText input at " + phys.x + "," + phys.y, "info", node.id);
  return true;
};

const mouseHoverGround: CapabilityHandler = async (ctx, node, args) => {
  const { x, y } = await locateFor(args, node);
  const phys = await toPhysical(x, y);
  await powershell(coordinateScript(phys.x, phys.y, "hover"), 15000);
  ctx.log("CV_MouseHover hover at " + phys.x + "," + phys.y, "info", node.id);
  return true;
};

const mouseClickGround: CapabilityHandler = async (ctx, node, args) => {
  const { x, y } = await locateFor(args, node);
  const phys = await toPhysical(x, y);
  const clickway = String(args.clickway ?? "0");
  const action = clickway === "1" || /double/i.test(clickway) ? "doubleClick" as const : "click" as const;
  await powershell(coordinateScript(phys.x, phys.y, action), 15000);
  ctx.log("CV_MouseClick " + action + " at " + phys.x + "," + phys.y, "info", node.id);
  return true;
};

register("CV_GetText", getTextGround);
register("CV_SetText", setTextGround);
register("CV_MouseHover", mouseHoverGround);
register("CV_MouseClick", mouseClickGround);