import type {
  AgentCategoryPath,
  AgentPresetLibraryCategoryNode,
  AgentPresetLibraryConfig,
  AgentPresetLibrarySection,
} from "@/types/agent";

export const AGENT_PRESET_LIBRARY_CONFIG_KEY = "agent_preset_library_config";
export const AGENT_PRESET_LIBRARY_MAX_DEPTH = 3;
export const AGENT_PRESET_LIBRARY_MY_WORKS_ID = "my-works";
export const AGENT_PRESET_LIBRARY_DEFAULT_SECTION_ID = "cases";

function normalizeText(value: unknown, maxLength: number) {
  return String(value || "").trim().slice(0, maxLength);
}

function normalizeBoolean(value: unknown, fallback: boolean) {
  return typeof value === "boolean" ? value : fallback;
}

function normalizeNumber(value: unknown, fallback: number, max = 999) {
  const parsed = Number(value);
  if (!Number.isFinite(parsed)) return fallback;
  return Math.max(0, Math.min(max, Math.round(parsed)));
}

function normalizeId(value: unknown, fallback: string) {
  const normalized = String(value || "")
    .trim()
    .slice(0, 64)
    .replace(/\s+/g, "_")
    .replace(/[^\w-]/g, "_")
    .replace(/_+/g, "_")
    .replace(/^_+|_+$/g, "")
    .toLowerCase();
  return normalized || fallback;
}

function createDefaultSection(
  id: string,
  label: string,
  sortOrder: number
): AgentPresetLibrarySection {
  return {
    id,
    label,
    description: "",
    enabled: true,
    sortOrder,
    categories: [],
  };
}

export const defaultAgentPresetLibraryConfig: AgentPresetLibraryConfig = {
  sections: [
    createDefaultSection("cases", "案例广场", 0),
    createDefaultSection("personal-assets", "个人资产库", 1),
    createDefaultSection("company-assets", "公司资产库", 2),
  ],
};

function normalizeNodeArray(
  input: unknown,
  depth: number,
  usedIds: Set<string>
): AgentPresetLibraryCategoryNode[] {
  if (!Array.isArray(input) || depth > AGENT_PRESET_LIBRARY_MAX_DEPTH) {
    return [];
  }

  return input
    .map((item, index) => {
      const raw =
        item && typeof item === "object" && !Array.isArray(item)
          ? (item as Record<string, unknown>)
          : {};
      const name = normalizeText(raw.name, 64) || `分类${index + 1}`;
      const baseId = normalizeId(raw.id, `category_${depth}_${index + 1}`);
      let id = baseId;
      let duplicateIndex = 2;
      while (usedIds.has(id)) {
        id = `${baseId}_${duplicateIndex}`;
        duplicateIndex += 1;
      }
      usedIds.add(id);

      return {
        id,
        name,
        enabled: normalizeBoolean(raw.enabled, true),
        sortOrder: normalizeNumber(raw.sortOrder, index),
        children:
          depth < AGENT_PRESET_LIBRARY_MAX_DEPTH
            ? normalizeNodeArray(raw.children, depth + 1, usedIds)
            : [],
      };
    })
    .sort((left, right) => left.sortOrder - right.sortOrder);
}

export function normalizeAgentPresetLibraryConfig(
  value: unknown
): AgentPresetLibraryConfig {
  const raw =
    value && typeof value === "object" && !Array.isArray(value)
      ? (value as Record<string, unknown>)
      : {};
  const hasRawSections = Array.isArray(raw.sections);
  const rawSections: unknown[] = hasRawSections
    ? (raw.sections as unknown[])
    : defaultAgentPresetLibraryConfig.sections;
  const usedSectionIds = new Set<string>();

  const sections = rawSections
    .map((item: unknown, index: number) => {
      const record =
        item && typeof item === "object" && !Array.isArray(item)
          ? (item as Record<string, unknown>)
          : {};
      const fallbackSection =
        defaultAgentPresetLibraryConfig.sections[index] ||
        createDefaultSection(`section_${index + 1}`, `分类页${index + 1}`, index);
      const baseId = normalizeId(record.id, fallbackSection.id);
      let id = baseId;
      let duplicateIndex = 2;
      while (usedSectionIds.has(id)) {
        id = `${baseId}_${duplicateIndex}`;
        duplicateIndex += 1;
      }
      usedSectionIds.add(id);

      const usedNodeIds = new Set<string>();

      return {
        id,
        label: normalizeText(record.label, 64) || fallbackSection.label,
        description: normalizeText(record.description, 200) || "",
        enabled: normalizeBoolean(record.enabled, true),
        sortOrder: normalizeNumber(record.sortOrder, fallbackSection.sortOrder ?? index),
        categories: normalizeNodeArray(record.categories, 1, usedNodeIds),
      };
    })
    .sort(
      (left: AgentPresetLibrarySection, right: AgentPresetLibrarySection) =>
        left.sortOrder - right.sortOrder
    );

  return {
    sections: hasRawSections
      ? sections
      : sections.length > 0
        ? sections
        : defaultAgentPresetLibraryConfig.sections,
  };
}

export function getEnabledAgentPresetLibrarySections(
  config: AgentPresetLibraryConfig
) {
  return [...config.sections]
    .filter((section) => section.enabled !== false)
    .sort((left, right) => left.sortOrder - right.sortOrder);
}

export function getEnabledAgentPresetLibraryNodes(
  nodes: AgentPresetLibraryCategoryNode[]
): AgentPresetLibraryCategoryNode[] {
  return [...nodes]
    .filter((node) => node.enabled !== false)
    .sort((left, right) => left.sortOrder - right.sortOrder)
    .map((node) => ({
      ...node,
      children: getEnabledAgentPresetLibraryNodes(node.children || []),
    }));
}

function findNodeByMatcher(
  nodes: AgentPresetLibraryCategoryNode[],
  matcher: (node: AgentPresetLibraryCategoryNode) => boolean
): AgentPresetLibraryCategoryNode | null {
  for (const node of nodes) {
    if (matcher(node)) {
      return node;
    }
    const foundChild = findNodeByMatcher(node.children || [], matcher);
    if (foundChild) {
      return foundChild;
    }
  }
  return null;
}

export function normalizeAgentCategoryPath(value: unknown): AgentCategoryPath {
  const raw =
    value && typeof value === "object" && !Array.isArray(value)
      ? (value as Record<string, unknown>)
      : {};

  return {
    sectionId: normalizeText(raw.sectionId, 64) || null,
    sectionName: normalizeText(raw.sectionName, 64) || null,
    level1Id: normalizeText(raw.level1Id, 64) || null,
    level1Name: normalizeText(raw.level1Name, 64) || normalizeText(raw.productCategory, 64) || null,
    level2Id: normalizeText(raw.level2Id, 64) || null,
    level2Name: normalizeText(raw.level2Name, 64) || normalizeText(raw.audienceTag, 64) || null,
    level3Id: normalizeText(raw.level3Id, 64) || null,
    level3Name: normalizeText(raw.level3Name, 64) || normalizeText(raw.usageScenario, 64) || null,
    productCategory: normalizeText(raw.productCategory, 64) || null,
    audienceTag: normalizeText(raw.audienceTag, 64) || null,
    usageScenario: normalizeText(raw.usageScenario, 64) || null,
    brand: normalizeText(raw.brand, 64) || null,
  };
}

export interface ResolvedAgentPresetCategoryPath {
  section: AgentPresetLibrarySection | null;
  level1: AgentPresetLibraryCategoryNode | null;
  level2: AgentPresetLibraryCategoryNode | null;
  level3: AgentPresetLibraryCategoryNode | null;
  sectionId: string | null;
  sectionName: string | null;
  level1Id: string | null;
  level1Name: string | null;
  level2Id: string | null;
  level2Name: string | null;
  level3Id: string | null;
  level3Name: string | null;
}

export function resolveAgentPresetCategoryPath(params: {
  categoryPath?: AgentCategoryPath | null;
  config?: AgentPresetLibraryConfig | null;
}) : ResolvedAgentPresetCategoryPath {
  const normalizedPath = normalizeAgentCategoryPath(params.categoryPath);
  const config = normalizeAgentPresetLibraryConfig(
    params.config || defaultAgentPresetLibraryConfig
  );
  const sections = getEnabledAgentPresetLibrarySections(config);
  const fallbackSection =
    sections.find((section) => section.id === AGENT_PRESET_LIBRARY_DEFAULT_SECTION_ID) ||
    sections[0] ||
    null;

  const section =
    sections.find((item) => item.id === normalizedPath.sectionId) ||
    sections.find((item) => item.label === normalizedPath.sectionName) ||
    ((!normalizedPath.sectionId &&
      !normalizedPath.sectionName &&
      (normalizedPath.level1Name || normalizedPath.level2Name || normalizedPath.level3Name)) ||
    normalizedPath.productCategory ||
    normalizedPath.audienceTag ||
    normalizedPath.usageScenario
      ? fallbackSection
      : null);

  const level1 =
    section
      ? findNodeByMatcher(getEnabledAgentPresetLibraryNodes(section.categories), (node) => {
          return (
            node.id === normalizedPath.level1Id ||
            node.name === normalizedPath.level1Name ||
            node.name === normalizedPath.productCategory
          );
        })
      : null;
  const level2 =
    level1
      ? findNodeByMatcher(getEnabledAgentPresetLibraryNodes(level1.children || []), (node) => {
          return (
            node.id === normalizedPath.level2Id ||
            node.name === normalizedPath.level2Name ||
            node.name === normalizedPath.audienceTag
          );
        })
      : null;
  const level3 =
    level2
      ? findNodeByMatcher(getEnabledAgentPresetLibraryNodes(level2.children || []), (node) => {
          return (
            node.id === normalizedPath.level3Id ||
            node.name === normalizedPath.level3Name ||
            node.name === normalizedPath.usageScenario
          );
        })
      : null;

  return {
    section,
    level1,
    level2,
    level3,
    sectionId: section?.id || normalizedPath.sectionId || null,
    sectionName: section?.label || normalizedPath.sectionName || null,
    level1Id: level1?.id || normalizedPath.level1Id || null,
    level1Name:
      level1?.name || normalizedPath.level1Name || normalizedPath.productCategory || null,
    level2Id: level2?.id || normalizedPath.level2Id || null,
    level2Name:
      level2?.name || normalizedPath.level2Name || normalizedPath.audienceTag || null,
    level3Id: level3?.id || normalizedPath.level3Id || null,
    level3Name:
      level3?.name || normalizedPath.level3Name || normalizedPath.usageScenario || null,
  };
}

export function buildAgentPresetCategoryPath(params: {
  section?: AgentPresetLibrarySection | null;
  level1?: AgentPresetLibraryCategoryNode | null;
  level2?: AgentPresetLibraryCategoryNode | null;
  level3?: AgentPresetLibraryCategoryNode | null;
}): AgentCategoryPath | null {
  const section = params.section || null;
  const level1 = params.level1 || null;
  const level2 = params.level2 || null;
  const level3 = params.level3 || null;

  if (!section && !level1 && !level2 && !level3) {
    return null;
  }

  const nextPath: AgentCategoryPath = {};

  if (section?.id) nextPath.sectionId = section.id;
  if (section?.label) nextPath.sectionName = section.label;
  if (level1?.id) nextPath.level1Id = level1.id;
  if (level1?.name) {
    nextPath.level1Name = level1.name;
    nextPath.productCategory = level1.name;
  }
  if (level2?.id) nextPath.level2Id = level2.id;
  if (level2?.name) {
    nextPath.level2Name = level2.name;
    nextPath.audienceTag = level2.name;
  }
  if (level3?.id) nextPath.level3Id = level3.id;
  if (level3?.name) {
    nextPath.level3Name = level3.name;
    nextPath.usageScenario = level3.name;
  }

  return Object.keys(nextPath).length > 0 ? nextPath : null;
}