import "server-only";

import type { AgentPsdFont } from "@/lib/agents/psd-font-config";
import {
  doesPsdFontMatchDetectedNames,
  findBestMatchingPsdFont,
} from "@/lib/agents/psd-font-matching";
import { readAgentPsdFonts } from "@/lib/agents/psd-font-settings";
import {
  AGENT_PSD_TEMPLATE_ASSET_VERSION,
  isAgentPsdImageLayerSlot,
  isAgentPsdLayerSuperLocked,
  isAgentPsdTemplateLayerUserEditable,
  isAgentPsdTextLayerSlot,
  type AgentPsdTemplate,
} from "@/lib/agents/psd-template-config";
import {
  isPsdAdjustmentLikeImageLayer,
  pickPrimaryPsdImageLayerId,
} from "@/lib/agents/psd-template-image-slot-selection";
import {
  parsePsdTemplateFileFromSource,
  preparePsdTemplateRenderAssets,
} from "@/lib/agents/psd-template-parser";
import { resolveAgentPsdLocalCachePath } from "@/lib/agents/psd-local-cache";
import { createStorageUploadSession } from "@/lib/storage/service";

function hasMissingLayerAssets(template: AgentPsdTemplate) {
  const hasRenderBase = hasDedicatedRenderBase(template);

  return template.layers.some(
    (layer) => {
      if (
        isAgentPsdTemplateLayerUserEditable(layer) &&
        !String(layer.previewUrl || "").trim()
      ) {
        return true;
      }

      if (hasRenderBase) {
        return (
          isAgentPsdImageLayerSlot(layer) &&
          isAgentPsdTemplateLayerUserEditable(layer) &&
          !String(layer.sourceUrl || "").trim()
        );
      }

      return !String(layer.sourceUrl || "").trim();
    }
  );
}

function needsTextMetadataRepair(template: AgentPsdTemplate) {
  return template.layers.some(
    (layer) =>
      isAgentPsdTextLayerSlot(layer) &&
      (!String(layer.detectedFontName || "").trim() ||
        !Array.isArray(layer.detectedFontNames) ||
        layer.detectedFontNames.length === 0)
  );
}

function hasDedicatedRenderBase(template: AgentPsdTemplate) {
  const renderBaseUrl = String(template.renderBaseUrl || "").trim();
  const previewUrl = String(template.previewUrl || "").trim();
  return Boolean(renderBaseUrl) && renderBaseUrl !== previewUrl;
}

function repairEditableImageLayerSelection(template: AgentPsdTemplate) {
  const imageLayers = template.layers.filter(isAgentPsdImageLayerSlot);
  const unlockedImageLayers = imageLayers.filter(
    (layer) => !isAgentPsdLayerSuperLocked(layer)
  );
  if (unlockedImageLayers.length === 0) {
    return template.layers;
  }

  const editableImageLayers = unlockedImageLayers.filter(
    isAgentPsdTemplateLayerUserEditable
  );
  const defaultImageLayer = unlockedImageLayers.find(
    (layer) =>
      isAgentPsdTemplateLayerUserEditable(layer) && layer.isDefaultResultSource
  );
  const shouldAutoRepairSelection =
    editableImageLayers.length === 0 ||
    !defaultImageLayer ||
    (editableImageLayers.length === 1 && isPsdAdjustmentLikeImageLayer(editableImageLayers[0]));

  if (!shouldAutoRepairSelection) {
    return template.layers;
  }

  const nextPrimaryLayerId = pickPrimaryPsdImageLayerId({
    imageLayers: unlockedImageLayers,
    canvasWidth: template.width,
    canvasHeight: template.height,
  });

  if (!nextPrimaryLayerId) {
    return template.layers;
  }

  const currentPrimaryLayerId = defaultImageLayer?.id || editableImageLayers[0]?.id || "";
  if (currentPrimaryLayerId === nextPrimaryLayerId) {
    return template.layers;
  }

  return template.layers.map((layer) => {
    if (!isAgentPsdImageLayerSlot(layer)) {
      return layer;
    }

    if (layer.id === nextPrimaryLayerId) {
      return {
        ...layer,
        isEditable: true,
        isDefaultResultSource: true,
        allowUserUploadOverride: true,
      };
    }

    if (layer.id === currentPrimaryLayerId) {
      return {
        ...layer,
        isEditable: false,
        isDefaultResultSource: false,
        allowUserUploadOverride: false,
      };
    }

    return layer;
  });
}

function toArrayBuffer(buffer: Buffer) {
  return buffer.buffer.slice(
    buffer.byteOffset,
    buffer.byteOffset + buffer.byteLength
  ) as ArrayBuffer;
}

export function repairAgentPsdTemplateFontBindings(
  template: AgentPsdTemplate,
  fonts: AgentPsdFont[]
) {
  if (fonts.length === 0) {
    return template;
  }

  const fontMap = new Map(fonts.map((font) => [font.id, font]));
  let didChange = false;

  const nextLayers = template.layers.map((layer) => {
    if (!isAgentPsdTextLayerSlot(layer) || layer.styleSource === "custom") {
      return layer;
    }

    const detectedFontNames = [
      ...((layer.detectedFontNames || []).filter(Boolean)),
      ...(layer.detectedFontName ? [layer.detectedFontName] : []),
    ];
    const preferredDetectedFontName =
      detectedFontNames.find((entry) => String(entry || "").trim()) || "";
    const currentFont = layer.fontId ? fontMap.get(layer.fontId) : undefined;
    const currentFontMatches = currentFont
      ? doesPsdFontMatchDetectedNames({
          detectedFontNames,
          font: currentFont,
        })
      : false;
    const matchedFont = findBestMatchingPsdFont({
      detectedFontNames,
      fonts,
    });

    if (
      matchedFont?.confidence === "high" &&
      (!currentFontMatches || !layer.fontId)
    ) {
      didChange = true;
      return {
        ...layer,
        fontId: matchedFont.font.id,
        fontFamily: matchedFont.font.family,
        fontLabel: matchedFont.font.name,
        fontFileUrl: matchedFont.font.fileUrl,
        fontContentType: matchedFont.font.contentType,
      };
    }

    if (
      !matchedFont &&
      !currentFontMatches &&
      (
        layer.fontId ||
        layer.fontFileUrl ||
        layer.fontContentType ||
        (preferredDetectedFontName &&
          (
            layer.fontFamily !== preferredDetectedFontName ||
            layer.fontLabel !== preferredDetectedFontName
          ))
      )
    ) {
      didChange = true;
      return {
        ...layer,
        fontId: undefined,
        fontFamily: preferredDetectedFontName || undefined,
        fontLabel: preferredDetectedFontName || undefined,
        fontFileUrl: undefined,
        fontContentType: undefined,
      };
    }

    if (currentFont && (
      layer.fontFamily !== currentFont.family ||
      layer.fontLabel !== currentFont.name ||
      layer.fontFileUrl !== currentFont.fileUrl ||
      layer.fontContentType !== currentFont.contentType
    )) {
      didChange = true;
      return {
        ...layer,
        fontFamily: currentFont.family,
        fontLabel: currentFont.name,
        fontFileUrl: currentFont.fileUrl,
        fontContentType: currentFont.contentType,
      };
    }

    return layer;
  });

  if (!didChange) {
    return template;
  }

  return {
    ...template,
    layers: nextLayers,
    updatedAt: new Date().toISOString(),
  } satisfies AgentPsdTemplate;
}

export async function repairAgentPsdTemplateAssetsIfNeeded(
  template: AgentPsdTemplate
) {
  if (template.parseStatus !== "completed") {
    return template;
  }

  const needsAssetVersionRefresh =
    Number(template.assetVersion || 0) !== AGENT_PSD_TEMPLATE_ASSET_VERSION;
  const needsRepair = needsAssetVersionRefresh || hasMissingLayerAssets(template);
  const needsRenderBaseRepair = !hasDedicatedRenderBase(template);
  const fonts = await readAgentPsdFonts().catch(() => []);
  const needsFontDetection = needsTextMetadataRepair(template);

  let nextLayers = repairEditableImageLayerSelection(template);
  if (needsFontDetection) {
    try {
      const localFilePath = resolveAgentPsdLocalCachePath({
        templateId: template.id,
        fileName: template.fileName,
      });
      const parsedTemplate = await parsePsdTemplateFileFromSource({
        fileUrl: template.fileUrl,
        filePath: localFilePath,
      });
      const parsedTextLayerMap = new Map(
        parsedTemplate.layers
          .filter((layer) => layer.slotType === "text")
          .map((layer) => [layer.layerId, layer])
      );
      nextLayers = nextLayers.map((layer) => {
        if (!isAgentPsdTextLayerSlot(layer)) return layer;
        const parsedLayer = parsedTextLayerMap.get(layer.layerId);
        if (!parsedLayer) return layer;
        return {
          ...layer,
          detectedFontName: parsedLayer.detectedFontName || layer.detectedFontName,
          detectedFontNames: parsedLayer.detectedFontNames || layer.detectedFontNames,
          textColor:
            layer.styleSource !== "custom" &&
            (!String(layer.textColor || "").trim() || layer.textColor === "#111111") &&
            parsedLayer.detectedTextColor
              ? parsedLayer.detectedTextColor
              : layer.textColor,
        };
      });
    } catch (error) {
      console.warn("[PSD Template] failed to repair parsed text metadata:", {
        templateId: template.id,
        error,
      });
    }
  }

  const fontRepairedTemplate = repairAgentPsdTemplateFontBindings(
    {
      ...template,
      layers: nextLayers,
    },
    fonts
  );
  nextLayers = fontRepairedTemplate.layers;

  const hasFontRepair = nextLayers.some(
    (layer, index) => JSON.stringify(layer) !== JSON.stringify(template.layers[index])
  );

  if (!needsRepair && !hasFontRepair && !needsRenderBaseRepair) {
    return template;
  }

  try {
    const uploadAsset = await createStorageUploadSession();
    const preparedAssets = await preparePsdTemplateRenderAssets({
      templateId: template.id,
      fileUrl: template.fileUrl,
      filePath: resolveAgentPsdLocalCachePath({
        templateId: template.id,
        fileName: template.fileName,
      }),
      layers: nextLayers,
      forceRefreshLayerAssets: needsAssetVersionRefresh,
      uploadAsset,
    });
    const uploadedRenderBase =
      needsRenderBaseRepair
        ? await uploadAsset(
            `agent-psd-base-${template.id}-${Date.now()}.png`,
            toArrayBuffer(preparedAssets.renderBaseBuffer)
          )
        : null;

    return {
      ...template,
      renderBaseUrl: uploadedRenderBase?.url || template.renderBaseUrl,
      renderBasePath: uploadedRenderBase?.pathname || template.renderBasePath,
      layers: preparedAssets.layers,
      assetVersion: AGENT_PSD_TEMPLATE_ASSET_VERSION,
      updatedAt: new Date().toISOString(),
    } satisfies AgentPsdTemplate;
  } catch (error) {
    console.warn("[PSD Template] failed to repair template assets:", {
      templateId: template.id,
      error,
    });
    return template;
  }
}