"use client";

import { useEffect, useMemo, useState, type ChangeEvent } from "react";
import useSWR from "swr";
import { toast } from "sonner";
import {
  Download,
  Image as ImageIcon,
  Loader2,
  Sparkles,
  Type,
  Upload,
} from "lucide-react";
import { fetchUploadWithRetry } from "@/lib/client/upload-with-retry";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { Badge } from "@/components/ui/badge";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { ScrollArea } from "@/components/ui/scroll-area";
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
import { Textarea } from "@/components/ui/textarea";
import {
  isAgentPsdImageLayerSlot,
  isAgentPsdTextLayerSlot,
  type AgentPsdTemplate,
  type AgentPsdTemplateListResponse,
  type AgentPsdTemplateRenderResponse,
} from "@/lib/agents/psd-template-config";

const fetcher = (url: string) => fetch(url, { cache: "no-store" }).then((res) => res.json());

function createInitialState(template: AgentPsdTemplate | null, sourceImageUrl: string) {
  const imageAssignments: Record<string, string> = {};
  const textAssignments: Record<string, string> = {};

  if (!template) {
    return { imageAssignments, textAssignments };
  }

  for (const layer of template.layers) {
    if (isAgentPsdImageLayerSlot(layer) && layer.isDefaultResultSource && sourceImageUrl) {
      imageAssignments[layer.id] = sourceImageUrl;
    }
    if (isAgentPsdTextLayerSlot(layer) && layer.defaultText) {
      textAssignments[layer.id] = layer.defaultText;
    }
  }

  return { imageAssignments, textAssignments };
}

export function AgentPsdTemplateEditorDialog({
  open,
  onOpenChange,
  sourceImageUrl,
  brandName,
}: {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  sourceImageUrl: string | null;
  brandName?: string | null;
}) {
  const normalizedBrandName = String(brandName || "").trim();
  const { data, isLoading } = useSWR<AgentPsdTemplateListResponse>(
    open && normalizedBrandName
      ? `/api/psd-templates?brand=${encodeURIComponent(normalizedBrandName)}`
      : null,
    fetcher
  );
  const templates = useMemo(() => (data?.success ? data.templates : []), [data]);

  const [selectedTemplateId, setSelectedTemplateId] = useState<string>("");
  const [imageAssignments, setImageAssignments] = useState<Record<string, string>>({});
  const [textAssignments, setTextAssignments] = useState<Record<string, string>>({});
  const [uploadingSlotId, setUploadingSlotId] = useState<string | null>(null);
  const [isRendering, setIsRendering] = useState(false);
  const [renderedResultUrl, setRenderedResultUrl] = useState<string>("");

  const selectedTemplate = useMemo(
    () => templates.find((template) => template.id === selectedTemplateId) || null,
    [selectedTemplateId, templates]
  );

  const editableImageLayers = useMemo(
    () =>
      (selectedTemplate?.layers || []).filter((layer) =>
        isAgentPsdImageLayerSlot(layer)
      ),
    [selectedTemplate]
  );
  const editableTextLayers = useMemo(
    () =>
      (selectedTemplate?.layers || []).filter((layer) =>
        isAgentPsdTextLayerSlot(layer)
      ),
    [selectedTemplate]
  );
  const fixedLayerCount = useMemo(() => {
    if (!selectedTemplate) return 0;
    return Math.max(0, selectedTemplate.layerCount - selectedTemplate.layers.length);
  }, [selectedTemplate]);

  useEffect(() => {
    if (!open) return;

    if (templates.length > 0 && !templates.some((template) => template.id === selectedTemplateId)) {
      setSelectedTemplateId(templates[0].id);
    }
  }, [open, selectedTemplateId, templates]);

  useEffect(() => {
    if (!open) return;
    setRenderedResultUrl("");
    const initialState = createInitialState(selectedTemplate, sourceImageUrl || "");
    setImageAssignments(initialState.imageAssignments);
    setTextAssignments(initialState.textAssignments);
  }, [open, selectedTemplate, sourceImageUrl]);

  async function handleSlotUpload(slotId: string, event: ChangeEvent<HTMLInputElement>) {
    const file = event.target.files?.[0];
    if (!file) return;

    try {
      setUploadingSlotId(slotId);
      const formData = new FormData();
      formData.set("file", file);
      const response = await fetchUploadWithRetry(formData);
      const payload = await response.json();

      if (!response.ok || !payload.url) {
        throw new Error(payload.error || "图片上传失败");
      }

      setImageAssignments((current) => ({
        ...current,
        [slotId]: payload.url,
      }));
      toast.success("替换图片已上传");
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "素材上传失败");
    } finally {
      setUploadingSlotId(null);
      event.target.value = "";
    }
  }

  async function handleRender() {
    if (!selectedTemplate) {
      toast.error("请先选择 PSD 模板");
      return;
    }

    try {
      setIsRendering(true);
      const response = await fetch("/api/psd-templates/render", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          templateId: selectedTemplate.id,
          sourceImageUrl: sourceImageUrl || "",
          imageAssignments,
          textAssignments,
        }),
      });

      const payload = (await response.json()) as AgentPsdTemplateRenderResponse;
      if (!response.ok || !payload.success || !payload.result?.url) {
        throw new Error(payload.error || "PSD 模板渲染失败");
      }

      setRenderedResultUrl(payload.result.url);
      toast.success("模板替换结果已生成");
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "PSD 模板渲染失败");
    } finally {
      setIsRendering(false);
    }
  }

  function handleDownload() {
    if (!renderedResultUrl) return;
    window.open(renderedResultUrl, "_blank", "noopener,noreferrer");
  }

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent
        overlayClassName="bg-black/85 backdrop-blur-sm"
        className="flex h-[92vh] w-[96vw] max-w-[1600px] flex-col overflow-hidden border border-white/10 bg-[#09090b] p-0 text-white shadow-[0_30px_120px_rgba(0,0,0,0.65)]"
      >
        <DialogHeader className="border-b border-white/10 bg-[#09090b] px-6 py-5">
          <DialogTitle className="flex items-center gap-2">
            <Sparkles className="h-5 w-5 text-orange-500" />
            套用 PSD 模板
          </DialogTitle>
          <DialogDescription>
            这里是直接把当前图片和输入文字替换进 PSD 模板，不会再次调用 AI 生图模型。
          </DialogDescription>
        </DialogHeader>

        <div className="grid min-h-0 flex-1 grid-cols-1 overflow-hidden lg:grid-cols-[340px_minmax(0,1fr)] xl:grid-cols-[340px_minmax(0,1fr)_360px]">
          <div className="min-h-0 border-b border-white/10 bg-[#09090b] p-5 lg:border-b-0 lg:border-r">
            <ScrollArea className="h-full pr-4">
              <div className="space-y-4">
                <div className="space-y-2">
                  <Label>选择模板</Label>
                  <Select value={selectedTemplateId} onValueChange={setSelectedTemplateId}>
                    <SelectTrigger>
                      <SelectValue placeholder={isLoading ? "加载模板中..." : "请选择模板"} />
                    </SelectTrigger>
                    <SelectContent>
                      {templates.map((template) => (
                        <SelectItem key={template.id} value={template.id}>
                          {template.name}
                        </SelectItem>
                      ))}
                    </SelectContent>
                  </Select>
                </div>

                {selectedTemplate ? (
                  <>
                    <div className="mx-auto w-full max-w-[240px] overflow-hidden rounded-2xl border border-white/10 bg-white/5">
                      <div
                        style={{
                          aspectRatio: `${Math.max(1, selectedTemplate.width)} / ${Math.max(1, selectedTemplate.height)}`,
                        }}
                      >
                        <img
                          src={selectedTemplate.previewUrl}
                          alt={selectedTemplate.name}
                          className="h-full w-full object-contain"
                        />
                      </div>
                    </div>

                    <div className="flex flex-wrap items-center gap-2">
                      <Badge variant="secondary">{selectedTemplate.brandName}</Badge>
                      <Badge variant="secondary">
                        {selectedTemplate.width} x {selectedTemplate.height}
                      </Badge>
                      <Badge variant="outline">{editableImageLayers.length} 个可替换图片</Badge>
                      <Badge variant="outline">{editableTextLayers.length} 个可编辑文字</Badge>
                      {fixedLayerCount > 0 ? (
                        <Badge variant="outline">{fixedLayerCount} 个固定图层</Badge>
                      ) : null}
                    </div>

                    {selectedTemplate.description ? (
                      <div className="rounded-xl border border-white/10 bg-white/[0.03] p-3 text-sm text-muted-foreground">
                        {selectedTemplate.description}
                      </div>
                    ) : null}

                    <div className="rounded-xl border border-dashed border-white/15 bg-white/[0.02] p-3 text-xs leading-6 text-muted-foreground">
                      用户侧这里只会显示后台已经开放的槽位：
                      图片图层显示为“可替换图片”，文字图层显示为“可编辑文字”，其余固定图层不会出现在这里。
                    </div>

                    <Button
                      onClick={handleRender}
                      disabled={isRendering}
                      className="w-full bg-gradient-to-r from-orange-600 to-rose-600 hover:from-orange-500 hover:to-rose-500"
                    >
                      {isRendering ? (
                        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                      ) : (
                        <Sparkles className="mr-2 h-4 w-4" />
                      )}
                      应用模板并导出
                    </Button>
                  </>
                ) : (
                  <div className="rounded-2xl border border-dashed border-white/15 p-5 text-sm text-muted-foreground">
                    {isLoading
                      ? "正在加载可用模板..."
                      : normalizedBrandName
                        ? `当前品牌“${normalizedBrandName}”下还没有可用 PSD 模板，请先去后台配置。`
                        : "当前还没有启用的 PSD 模板，请先去后台配置。"}
                  </div>
                )}
              </div>
            </ScrollArea>
          </div>

          <div className="min-h-0 border-b border-white/10 bg-[#09090b] p-5 xl:border-b-0 xl:border-r">
            <div className="mb-4 flex flex-wrap items-center gap-2">
              <div className="text-sm font-medium">槽位内容</div>
              {selectedTemplate ? (
                <>
                  <Badge variant="outline">{editableImageLayers.length} 个可替换图片</Badge>
                  <Badge variant="outline">{editableTextLayers.length} 个可编辑文字</Badge>
                </>
              ) : null}
            </div>
            <div className="mb-4 text-xs text-muted-foreground">
              图片槽位直接替换图片，文字槽位直接修改文案，不会再次调用 AI 生图。
            </div>

            <ScrollArea className="h-full min-h-0 pr-4">
              {selectedTemplate ? (
                <div className="space-y-6">
                  <section className="space-y-3">
                    <div className="flex items-center justify-between gap-3">
                      <div className="text-sm font-medium">可替换图片</div>
                      <Badge variant="secondary">{editableImageLayers.length}</Badge>
                    </div>
                    {editableImageLayers.length > 0 ? (
                      editableImageLayers.map((layer) => {
                        const assignedUrl = imageAssignments[layer.id] || "";
                        const slotUploadInputId = `psd-slot-upload-${layer.id}`;

                        return (
                          <div key={layer.id} className="rounded-2xl border border-white/10 bg-white/[0.02] p-4">
                            <div className="flex flex-wrap items-center gap-2">
                              <div className="text-sm font-medium">{layer.layerName}</div>
                              <Badge variant="default">可替换图片</Badge>
                              {layer.isRequired ? <Badge variant="destructive">必传</Badge> : null}
                              {layer.isDefaultResultSource ? (
                                <Badge variant="secondary">默认使用当前图片</Badge>
                              ) : null}
                              <Badge variant="outline">
                                {layer.width} x {layer.height}
                              </Badge>
                            </div>
                            <div className="mt-1 text-xs text-muted-foreground">{layer.layerPath}</div>

                            {assignedUrl ? (
                              <div className="mt-3 overflow-hidden rounded-xl border border-white/10 bg-white/5">
                                <div className="aspect-[4/3]">
                                  <img
                                    src={assignedUrl}
                                    alt={layer.layerName}
                                    className="h-full w-full object-contain"
                                  />
                                </div>
                              </div>
                            ) : (
                              <div className="mt-3 flex aspect-[4/3] items-center justify-center rounded-xl border border-dashed border-white/15 bg-white/[0.02] text-xs text-muted-foreground">
                                暂未替换图片
                              </div>
                            )}

                            <div className="mt-3 flex flex-wrap gap-2">
                              {sourceImageUrl ? (
                                <Button
                                  type="button"
                                  variant="outline"
                                  size="sm"
                                  onClick={() =>
                                    setImageAssignments((current) => ({
                                      ...current,
                                      [layer.id]: sourceImageUrl,
                                    }))
                                  }
                                >
                                  使用当前图片
                                </Button>
                              ) : null}

                              {layer.allowUserUploadOverride ? (
                                <>
                                  <Input
                                    id={slotUploadInputId}
                                    className="hidden"
                                    type="file"
                                    accept="image/png,image/jpeg,image/webp"
                                    onChange={(event) => handleSlotUpload(layer.id, event)}
                                  />
                                  <Label htmlFor={slotUploadInputId} className="inline-flex">
                                    <Button
                                      type="button"
                                      variant="outline"
                                      size="sm"
                                      disabled={uploadingSlotId === layer.id}
                                      onClick={(event) => {
                                        if (uploadingSlotId === layer.id) {
                                          event.preventDefault();
                                        }
                                      }}
                                    >
                                      {uploadingSlotId === layer.id ? (
                                        <Loader2 className="mr-2 h-4 w-4 animate-spin" />
                                      ) : (
                                        <Upload className="mr-2 h-4 w-4" />
                                      )}
                                      上传替换图片
                                    </Button>
                                  </Label>
                                </>
                              ) : null}

                              {assignedUrl ? (
                                <Button
                                  type="button"
                                  variant="ghost"
                                  size="sm"
                                  onClick={() =>
                                    setImageAssignments((current) => {
                                      const nextAssignments = { ...current };
                                      delete nextAssignments[layer.id];
                                      return nextAssignments;
                                    })
                                  }
                                >
                                  清空
                                </Button>
                              ) : null}
                            </div>
                          </div>
                        );
                      })
                    ) : (
                      <div className="rounded-2xl border border-dashed border-white/15 p-5 text-sm text-muted-foreground">
                        这个模板当前没有开放可替换图片槽位。
                      </div>
                    )}
                  </section>

                  <section className="space-y-3">
                    <div className="flex items-center justify-between gap-3">
                      <div className="text-sm font-medium">可编辑文字</div>
                      <Badge variant="secondary">{editableTextLayers.length}</Badge>
                    </div>
                    {editableTextLayers.length > 0 ? (
                      editableTextLayers.map((layer) => {
                        const textValue = textAssignments[layer.id] || "";
                        return (
                          <div key={layer.id} className="rounded-2xl border border-white/10 bg-white/[0.02] p-4">
                            <div className="flex flex-wrap items-center gap-2">
                              <div className="text-sm font-medium">{layer.layerName}</div>
                              <Badge variant="default">可编辑文字</Badge>
                              {layer.isRequired ? <Badge variant="destructive">必填</Badge> : null}
                              <Badge variant="outline">
                                {layer.width} x {layer.height}
                              </Badge>
                              {layer.fontLabel || layer.fontFamily ? (
                                <Badge variant="secondary">{layer.fontLabel || layer.fontFamily}</Badge>
                              ) : null}
                            </div>
                            <div className="mt-1 text-xs text-muted-foreground">{layer.layerPath}</div>

                            <div className="mt-3 grid gap-3">
                              <Textarea
                                rows={4}
                                value={textValue}
                                placeholder={layer.placeholder || "请输入文字"}
                                onChange={(event) =>
                                  setTextAssignments((current) => ({
                                    ...current,
                                    [layer.id]: event.target.value,
                                  }))
                                }
                              />
                              <div className="flex flex-wrap gap-2 text-xs text-muted-foreground">
                                <span>字体：{layer.fontLabel || layer.fontFamily || "系统字体"}</span>
                                <span>字号：{layer.fontSize}px</span>
                                <span>行高：{layer.lineHeight}</span>
                                <span>对齐：{layer.textAlign}</span>
                              </div>
                            </div>
                          </div>
                        );
                      })
                    ) : (
                      <div className="rounded-2xl border border-dashed border-white/15 p-5 text-sm text-muted-foreground">
                        这个模板当前没有开放可编辑文字槽位。
                      </div>
                    )}
                  </section>
                </div>
              ) : (
                <div className="rounded-2xl border border-dashed border-white/15 p-5 text-sm text-muted-foreground">
                  {normalizedBrandName ? "请先选择一个模板。" : "请先在工作流中选择品牌后再使用 PSD 模板。"}
                </div>
              )}
            </ScrollArea>
          </div>

          <div className="min-h-0 bg-[#09090b] p-5">
            <div className="mb-4">
              <div className="text-sm font-medium">导出结果</div>
              <div className="mt-1 text-xs text-muted-foreground">
                直接完成模板替换后，这里会显示最终导出的成品图。
              </div>
            </div>

            {renderedResultUrl ? (
              <div className="flex h-full min-h-0 flex-col justify-between gap-4">
                <div className="mx-auto w-full max-w-[280px] overflow-hidden rounded-2xl border border-white/10 bg-white/5">
                  <div
                    style={{
                      aspectRatio: selectedTemplate
                        ? `${Math.max(1, selectedTemplate.width)} / ${Math.max(1, selectedTemplate.height)}`
                        : "1 / 1",
                    }}
                  >
                    <img
                      src={renderedResultUrl}
                      alt="PSD 模板导出结果"
                      className="h-full w-full object-contain"
                    />
                  </div>
                </div>

                <Button onClick={handleDownload} className="w-full">
                  <Download className="mr-2 h-4 w-4" />
                  下载结果图
                </Button>
              </div>
            ) : (
              <div className="flex h-full min-h-0 flex-col items-center justify-center rounded-2xl border border-dashed border-white/15 bg-white/[0.02] px-6 text-center">
                <div className="flex h-16 w-16 items-center justify-center rounded-2xl bg-white/5">
                  {editableTextLayers.length > 0 ? (
                    <Type className="h-8 w-8 text-muted-foreground" />
                  ) : (
                    <ImageIcon className="h-8 w-8 text-muted-foreground" />
                  )}
                </div>
                <div className="mt-4 text-sm font-medium">还未导出成品图</div>
                <div className="mt-2 text-xs leading-6 text-muted-foreground">
                  {normalizedBrandName
                    ? "确认替换图片和文字后，点击“应用模板并导出”，这里会显示最终图片。"
                    : "请先返回工作流区域选择品牌，再打开 PSD 模板。"}
                </div>
              </div>
            )}
          </div>
        </div>
      </DialogContent>
    </Dialog>
  );
}