/* js/ai.js
 * Munjanara Image Editor - AI Edit Module
 * - requires globals from image-editor.js:
 *   canvas, img, cropper, canvasWidth, canvasHeight
 *   addJsonToCanvas(jdata, filePath?), setImageAttr()
 */

(function () {
  "use strict";

  // ---------- UI ids ----------
  const IDS = {
    preset: "aiPreset2",
    prompt: "aiPrompt2",
    apply: "btnAiApply2",
    undo: "btnAiUndo2",
    refPick: "btnAiRefPick2",
    refFile: "aiRefFile2",
    refName: "aiRefName2",
    overlay: "aiOverlay2",
    ovTitle: "aiOvTitle2",
    ovDesc: "aiOvDesc2",
    cancel: "aiCancel2",
  };

  // ---------- State ----------
  const AI_HISTORY_MAX = 4;
  let aiPrevStackMap = {};
  let controller = null;
  let undoPreviewBackup = null;     // hover ½ÃÀÛ ½Ã ÇöÀç »óÅ ¹é¾÷(JSON)
  let undoPreviewing = false;       // ÇöÀç ÇÁ¸®ºä ÁßÀÎÁö
  let undoPreviewTimer = null;      // ºü¸¥ Åä±Û ¹æÁö¿ë(¼±ÅÃ)

  // ---------- Helpers ----------
  function $(id) {
    return document.getElementById(id);
  }

  function safeAlert(msg) {
    try {
      if (typeof Alert === "function") Alert(msg);
      else alert(msg);
    } catch (_) {
      alert(msg);
    }
  }

  function getCurrentStack() {
    const idx = window.jobIndex ?? 0;
    if (!aiPrevStackMap[idx]) {
      aiPrevStackMap[idx] = [];
    }
    return aiPrevStackMap[idx];
  }


  function setBusy(on, title, desc) {
    const ov = $(IDS.overlay);
    const t = $(IDS.ovTitle);
    const d = $(IDS.ovDesc);
    const btnApply = $(IDS.apply);
    const btnUndo = $(IDS.undo);

    if (!ov) return;

    if (on) {
      if (t) t.textContent = title || "AI ó¸®Áß¡¦";
      if (d) d.textContent = desc || "¿äû»çÇ×À» Àû¿ëÇÏ°í ÀÖ½À´Ï´Ù.";
      ov.style.display = "flex";
      if (btnApply) btnApply.disabled = true;
      if (btnUndo) btnUndo.disabled = true;
    } else {
      ov.style.display = "none";
      if (btnApply) btnApply.disabled = false;
    }
  }

  function syncUndoBtn() {
    const btn = $(IDS.undo);
    if (!btn) return;
  
    const stack = getCurrentStack();
    btn.disabled = stack.length === 0;
  }

  function pushUndoState() {
    try {
      if (!window.canvas) return;
      const snap = window.canvas.toJSON();
  
      const stack = getCurrentStack();
      stack.push(snap);
  
      while (stack.length > AI_HISTORY_MAX) {
        stack.shift();
      }
  
      syncUndoBtn();
    } catch (_) {}
  }

  function dataURLToBlob(dataUrl) {
    const arr = String(dataUrl).split(",");
    const mime = (arr[0].match(/:(.*?);/) || [])[1] || "image/png";
    const bstr = atob(arr[1] || "");
    let n = bstr.length;
    const u8 = new Uint8Array(n);
    while (n--) u8[n] = bstr.charCodeAt(n);
    return new Blob([u8], { type: mime });
  }

  function removeCropperIfAny() {
    try {
      if (window.cropper && window.canvas) {
        window.canvas.remove(window.cropper);
        window.cropper = null;
      }
    } catch (_) {}
  }

  async function callAiEdit() {
    if (!window.img) {
      safeAlert("±âº» À̹ÌÁö°¡ ¼±ÅõÇÁö ¾Ê¾Ò½À´Ï´Ù.");
      return;
    }

    const promptEl = $(IDS.prompt);
    const prompt = (promptEl ? promptEl.value : "").trim();
    if (!prompt) {
      safeAlert("¿äû»çÇ×À» ÀÔ·ÂÇØÁÖ¼¼¿ä.");
      return;
    }

    var objCnt = canvas.getObjects().length;

    if (objCnt >= 2 && !confirm("AI¿äû½Ã ÇØ´ç À̹ÌÁö°¡ ÅëÀ̹ÌÁö·Î º¯°æµË´Ï´Ù.\nÁøÇàÇϽðڽÀ´Ï±î?")) return;

    controller = new AbortController();

    try {
      
      setBusy(true, "AI ó¸®Áß¡¦", "¿äû»çÇ×À» Àû¿ëÇÏ°í ÀÖ½À´Ï´Ù.");

      // undo ½º³À¼¦
      pushUndoState();

      const resultDurl = makeDataURL(jobIndex);
      const blob = dataURLToBlob(resultDurl);
      const ext = (blob.type === "image/jpeg") ? "jpg" : "png";
      const file = new File([blob], `ai_result.${ext}`, { type: blob.type });

      const fd = new FormData();
      fd.append("action", "ai_apply");
      fd.append("ai_user_prompt", prompt);
      fd.append("image", file);

      const refFile = $(IDS.refFile)?.files?.[0] || null;
      if (refFile) fd.append("ref_image", refFile);

      const res = await fetch(location.href, {
        method: "POST",
        body: fd,
        signal: controller.signal,
      });

      if (res.status === 401) {
        setBusy(false);
        safeAlert("·Î±×ÀÎ ÈÄ ÀÌ¿ëÇØ ÁÖ¼¼¿ä.");
        return;
      }

      if (res.status === 429) {
        let j = {};
        try {
          j = await res.json();
        } catch (_) {}
        setBusy(false);
        safeAlert(j?.error === "DAILY_LIMIT" ? "AI¿äûÀº ÀÏÀÏ »ç¿ë·®ÀÌ Á¦Çѵ˴ϴÙ. ³»ÀÏ ´Ù½Ã ÀÌ¿ëÇØÁÖ¼¼¿ä." : "¿äûÀÌ ³Ê¹« ¸¹½À´Ï´Ù. Àá½Ã ÈÄ ´Ù½Ã ½ÃµµÇØ ÁÖ¼¼¿ä.");
        return;
      }

      const data = await res.json();
      if (!data || !data.ok || !data.image) {
        setBusy(false);
        safeAlert("AI°¡ À̹ÌÁö¸¦ »ý¼ºÇÏÁö ¸øÇß½À´Ï´Ù.<br>- À̹ÌÁö¿¡ ¸ÂÁö ¾Ê°Å³ª »çȸÀû ºÐÀ§±â¿¡ ¹ÝÇÏ´Â ¿äû -");
        return;
      }

      applyAiResultAsUpload(data.image);

      if ($(IDS.refFile)) $(IDS.refFile).value = "";
      if ($(IDS.refName)) $(IDS.refName).textContent = "¾øÀ½";

      setBusy(false);
      syncUndoBtn();

      imageCate = 7;
      makeType = "ai_image";

      setGuestCount(makeType);
    } catch (e) {
      setBusy(false);
      if (e?.name === "AbortError") safeAlert("ÀÛ¾÷ÀÌ Ãë¼ÒµÇ¾ú½À´Ï´Ù.");
      else {
        console.error(e);
        safeAlert("½Ã½ºÅÛ ¿À·ù°¡ ¹ß»ýÇß½À´Ï´Ù.");
      }
    } finally {
      controller = null;
    }
  }

  function bindUi() {
    const presetEl = $(IDS.preset);
    const promptEl = $(IDS.prompt);
    const applyBtn = $(IDS.apply);
    const undoBtn = $(IDS.undo);
    const refPick = $(IDS.refPick);
    const refFile = $(IDS.refFile);
    const refName = $(IDS.refName);
    const cancelBtn = $(IDS.cancel);

    if (!applyBtn || !promptEl) return false;

    if (presetEl) {
      presetEl.addEventListener("change", () => {
        const v = (presetEl.value || "").trim();
        if (!v) return;
        promptEl.value = v;
        //presetEl.value = "";
        promptEl.focus();
      });
    }

    if (refPick && refFile) {
      refPick.addEventListener("click", () => refFile.click());
    }
    if (refFile && refName) {
      refFile.addEventListener("change", (e) => {
        const f = e.target.files?.[0];
        refName.textContent = f ? f.name : "¾øÀ½";
      });
    }

    if (cancelBtn) {
      cancelBtn.addEventListener("click", () => {
        try {
          if (controller) controller.abort();
        } catch (_) {}
        setBusy(false);
        syncUndoBtn();
      });
    }

    applyBtn.addEventListener("click", callAiEdit);

    if (undoBtn) {
      undoBtn.addEventListener("click", () => {
        if (undoPreviewing) endUndoPreview();

        const stack = getCurrentStack();
        if (stack.length === 0) return;
      
        if (!confirm("ÀÌÀü »óÅ·ΠµÇµ¹¸®½Ã°Ú½À´Ï±î?")) return;
      
        const prev = stack.pop();
        syncUndoBtn();
      
        if (typeof window.addJsonToCanvas === "function") {
          window.addJsonToCanvas(prev);
        } else {
          safeAlert("º¹¿ø ÇÔ¼ö(addJsonToCanvas)¸¦ ãÁö ¸øÇß½À´Ï´Ù.");
        }
      });
    }

    // ===== Undo hover preview (ºñ±³ ¹Ì¸®º¸±â) =====
    function startUndoPreview() {
      if (!undoBtn || undoBtn.disabled) return;
      if (undoPreviewing) return;
    
      // AI ó¸®Áß ¿À¹ö·¹ÀÌ ¶°ÀÖÀ¸¸é ºñ±³ ¹Ì¸®º¸±â ±ÝÁö(¿øÇϸé Á¦°Å °¡´É)
      const ov = $(IDS.overlay);
      if (ov && ov.style.display !== "none") return;
    
      const stack = getCurrentStack();
      if (!stack || stack.length === 0) return;
    
      // ÇöÀç »óÅ ¹é¾÷ (µÇµ¹¾Æ¿Ã ¿ëµµ)
      try {
        undoPreviewBackup = window.canvas.toJSON();
      } catch (_) {
        undoPreviewBackup = null;
        return;
      }
    
      // Á÷Àü »óÅÂ(POPÇÏÁö ¾ÊÀ½!)·Î ¹Ì¸®º¸±â
      const prev = stack[stack.length - 1];
      undoPreviewing = true;
    
      try {
        if (typeof window.addJsonToCanvas === "function") {
          window.addJsonToCanvas(prev);
        }
      } catch (e) {
        console.error(e);
        undoPreviewing = false;
        undoPreviewBackup = null;
      }
    }
    
    function endUndoPreview() {
      if (!undoPreviewing) return;
      if (!undoPreviewBackup) {
        undoPreviewing = false;
        return;
      }
    
      try {
        if (typeof window.addJsonToCanvas === "function") {
          window.addJsonToCanvas(undoPreviewBackup);
        }
      } catch (e) {
        console.error(e);
      } finally {
        undoPreviewing = false;
        undoPreviewBackup = null;
      }
    }
    
    // µ¥½ºÅ©Å¾: hover
    undoBtn.addEventListener("mouseenter", () => {
      // (¼±ÅÃ) ºü¸£°Ô ½ºÄ¡¸é ±ôºýÀÏ ¼ö À־ 80ms µô·¹ÀÌ
      clearTimeout(undoPreviewTimer);
      undoPreviewTimer = setTimeout(startUndoPreview, 80);
    });
    undoBtn.addEventListener("mouseleave", () => {
      clearTimeout(undoPreviewTimer);
      endUndoPreview();
    });
    
    // ¸ð¹ÙÀÏ/ÅÍÄ¡: ´©¸£°í ÀÖ´Â µ¿¾È ºñ±³
    undoBtn.addEventListener("pointerdown", (e) => {
      // ¹öÆ° Ŭ¸¯(undo)°ú Ãæµ¹ ¹æÁö: "´­·¯¼­ ºñ±³"¸¸ ÇÏ°í ½ÍÀ¸¸é preventDefault
      // e.preventDefault();
      startUndoPreview();
    });
    undoBtn.addEventListener("pointerup", endUndoPreview);
    undoBtn.addEventListener("pointercancel", endUndoPreview);

    syncUndoBtn();
    return true;
  }

  function waitForEditorReady() {
    // Fabric canvas »ý¼º/Àü¿ªÇÔ¼ö ÁغñµÇ¸é ºÙÀÓ
    const maxTry = 200; // ~20s
    let t = 0;
    const timer = setInterval(() => {
      t++;
      const ok =
        window.canvas &&
        window.fabric &&
        typeof window.canvas.toJSON === "function" &&
        typeof window.addJsonToCanvas === "function" &&
        typeof window.setImageAttr === "function" &&
        $(IDS.apply); // UI Á¸Àç È®ÀÎ

      if (ok) {
        clearInterval(timer);
        bindUi();
      }
      if (t >= maxTry) {
        clearInterval(timer);
        console.warn("[ai.js] editor not ready - skipped binding");
      }
    }, 100);
  }

  function dataURLToFile(dataURL, filename = "ai_result.png") {
    const [header, b64] = dataURL.split(",");
    const mime = header.match(/data:(.*?);base64/)?.[1] || "image/png";
  
    const bin = atob(b64);
    const arr = new Uint8Array(bin.length);
  
    for (let i = 0; i < bin.length; i++) {
      arr[i] = bin.charCodeAt(i);
    }
  
    return new File([arr], filename, { type: mime });
  }

  function applyAiResultAsUpload(aiDataURL) {
    const file = dataURLToFile(aiDataURL, "ai_result.png");
    
    addImageToCanvas(file, 0); // 1:½ºÆ¼Ä¿, 0:±âº»À̹ÌÁö
  }

  syncUndoBtn();

  // DOMReady
  document.addEventListener("DOMContentLoaded", waitForEditorReady);
})();