'use client';

import { create } from 'zustand';
import type { Requirement, RequirementStatus, Effort, DictItem, SourceType, SourceTarget } from '@/lib/requirement';
import type { Priority } from '@/lib/derive';
import {
  createRequirementByProductId,
  deleteRequirementByProductId,
  updateRequirementByProductId,
  updateRequirementStatusByProductId,
} from '@/lib/domain-api';
import { api } from '@/lib/api';
import { scheduleSaveWithOptimisticRollback } from '@/lib/optimistic-persistence';
import { SERVER_DATA_CACHE_MS } from '@/lib/server-data';
import { loadV22RequirementsPage, type V22RequirementsQuery } from '@/lib/v22-api';
import { useAuthStore } from './useAuthStore';
import { useMemberStore } from './useMemberStore';

interface RequirementState {
  requirements: Requirement[];
  sourceTargets: SourceTarget[];
  types: DictItem[];
  platforms: DictItem[];
  loading: boolean;
  loaded: boolean;
  fetchRequirements: (options?: { force?: boolean; productId?: string; projectId?: string; versionId?: string }) => Promise<void>;
  createRequirement: (data: Omit<Requirement, 'id' | 'code' | 'createdAt'>) => void;
  updateRequirement: (id: string, data: Partial<Requirement>) => void;
  deleteRequirement: (id: string, productId?: string) => void;
  addSourceTarget: (name: string, sourceType: SourceType) => void;
  updateSourceTarget: (id: string, name: string) => void;
  deleteSourceTarget: (id: string) => void;
  addType: (name: string) => void;
  updateType: (id: string, name: string) => void;
  deleteType: (id: string) => void;
  addPlatform: (name: string) => void;
  updatePlatform: (id: string, name: string) => void;
  deletePlatform: (id: string) => void;
}

// --- Preset dictionaries ---

const PRESET_SOURCE_TARGETS: SourceTarget[] = [];

const PRESET_TYPES: DictItem[] = [
  { id: 'type-1', name: '新功能', createdAt: '2024-01-01' },
  { id: 'type-2', name: 'BUG修复', createdAt: '2024-01-01' },
  { id: 'type-3', name: '数据需求/埋点需求', createdAt: '2024-01-01' },
  { id: 'type-4', name: '优化需求', createdAt: '2024-01-01' },
  { id: 'type-5', name: '模块重构', createdAt: '2024-01-01' },
  { id: 'type-6', name: '缺陷修复', createdAt: '2024-01-01' },
  { id: 'type-7', name: '功能优化', createdAt: '2024-01-01' },
  { id: 'type-8', name: '插单/紧急需求', createdAt: '2024-01-01' },
];

const PRESET_PLATFORMS: DictItem[] = [
  { id: 'platform-1', name: 'Web', createdAt: '2024-01-01' },
  { id: 'platform-2', name: 'App(iOS)', createdAt: '2024-01-01' },
  { id: 'platform-3', name: 'App(Android)', createdAt: '2024-01-01' },
  { id: 'platform-4', name: '小程序', createdAt: '2024-01-01' },
  { id: 'platform-5', name: 'H5', createdAt: '2024-01-01' },
];

// --- Mock requirements ---

const MOCK_REQUIREMENTS: Requirement[] = [];
let lastRequirementsFetchAt = 0;

type RequirementGovernanceKind = 'requirement_type' | 'requirement_platform' | 'requirement_source';

interface GovernanceDictionaryRow {
  id: string;
  name: string;
  group?: string | null;
  createdAt?: string;
}

// --- Store ---

export const useRequirementStore = create<RequirementState>((set, get) => {
  return {
    requirements: MOCK_REQUIREMENTS,
    sourceTargets: PRESET_SOURCE_TARGETS,
    types: PRESET_TYPES,
    platforms: PRESET_PLATFORMS,
    loading: false,
    loaded: false,

    fetchRequirements: async (options) => {
      const hasRelationScope = Boolean(options?.productId);
      if (!hasRelationScope && !options?.force && get().loaded && Date.now() - lastRequirementsFetchAt < SERVER_DATA_CACHE_MS) return;
      const [governed, scopedRequirements] = await Promise.all([
        loadRequirementGovernanceDictionaries().catch(() => null),
        hasRelationScope ? loadScopedRequirementsFromRelation(options).catch(() => null) : Promise.resolve(null),
      ]);
      if (!hasRelationScope && !options?.force && get().loaded && Date.now() - lastRequirementsFetchAt < SERVER_DATA_CACHE_MS) return;
      lastRequirementsFetchAt = Date.now();
      set({
        requirements: scopedRequirements
          ? mergeRequirementsForScope(get().requirements, options, scopedRequirements)
          : get().requirements,
        sourceTargets: governed?.sourceTargets ?? PRESET_SOURCE_TARGETS,
        types: governed?.types ?? PRESET_TYPES,
        platforms: governed?.platforms ?? PRESET_PLATFORMS,
        loaded: true,
      });
    },

    createRequirement: (data) => {
      const { requirements } = get();
      const code = `REQ-${String(requirements.length + 1).padStart(3, '0')}`;
      const newReq: Requirement = {
        ...data,
        status: data.status ?? 'pending_review',
        id: `req-${Date.now()}`,
        code,
        createdAt: new Date().toISOString(),
      };
      const updated = [...requirements, newReq];
      set({ requirements: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          const created = await createRequirementByProductId(newReq.productId, newReq);
          set({
            requirements: get().requirements.map((item) => (
              item.id === newReq.id ? { ...created, creator: newReq.creator || created.creator } : item
            )),
            loaded: true,
          });
        },
        expected: updated,
        getCurrent: () => get().requirements,
        rollback: () => set({ requirements, loaded: true }),
      });
    },

    updateRequirement: (id, data) => {
      const { requirements } = get();
      const current = requirements.find((r) => r.id === id);
      const productId = data.productId ?? current?.productId;
      const updated = requirements.map((r) => (r.id === id ? { ...r, ...data } : r));
      set({ requirements: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          if (!productId) throw new Error('missing requirement productId');
          const domainPatch = { ...data };
          const status = domainPatch.status;
          delete domainPatch.status;
          delete domainPatch.productId;
          delete domainPatch.addedToVersionBy;
          if (hasDomainPatch(domainPatch)) {
            await updateRequirementByProductId(productId, id, domainPatch);
          }
          if (status) {
            await updateRequirementStatusByProductId(productId, id, status);
          }
        },
        expected: updated,
        getCurrent: () => get().requirements,
        rollback: () => set({ requirements, loaded: true }),
      });
    },

    deleteRequirement: (id, scopedProductId) => {
      const { requirements } = get();
      const productId = scopedProductId ?? requirements.find((r) => r.id === id)?.productId;
      const updated = requirements.filter((r) => r.id !== id);
      set({ requirements: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          if (!productId) throw new Error('missing requirement productId');
          await deleteRequirementByProductId(productId, id);
        },
        expected: updated,
        getCurrent: () => get().requirements,
        rollback: () => set({ requirements, loaded: true }),
      });
    },

    // --- SourceTarget dict ---
    addSourceTarget: (name, sourceType) => {
      const item: SourceTarget = { id: `st-${Date.now()}`, name, sourceType, createdAt: new Date().toISOString().slice(0, 10) };
      const { sourceTargets } = get();
      const updated = [...sourceTargets, item];
      set({ sourceTargets: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          const created = await createGovernanceDictionary('requirement_source', name, sourceType);
          set({
            sourceTargets: get().sourceTargets.map((target) => (
              target.id === item.id ? governanceRowToSourceTarget(created, sourceType) : target
            )),
            loaded: true,
          });
        },
        expected: updated,
        getCurrent: () => get().sourceTargets,
        rollback: () => set({ sourceTargets, loaded: true }),
      });
    },

    updateSourceTarget: (id, name) => {
      const { sourceTargets } = get();
      const current = sourceTargets.find((target) => target.id === id);
      const updated = sourceTargets.map((s) => (s.id === id ? { ...s, name } : s));
      set({ sourceTargets: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await updateGovernanceDictionary('requirement_source', id, name, current?.sourceType ?? 'customer');
        },
        expected: updated,
        getCurrent: () => get().sourceTargets,
        rollback: () => set({ sourceTargets, loaded: true }),
      });
    },

    deleteSourceTarget: (id) => {
      const { sourceTargets } = get();
      const updated = sourceTargets.filter((s) => s.id !== id);
      set({ sourceTargets: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await deleteGovernanceDictionary('requirement_source', id);
        },
        expected: updated,
        getCurrent: () => get().sourceTargets,
        rollback: () => set({ sourceTargets, loaded: true }),
      });
    },

    // --- Type dict ---
    addType: (name) => {
      const item: DictItem = { id: `type-${Date.now()}`, name, createdAt: new Date().toISOString().slice(0, 10) };
      const { types } = get();
      const updated = [...types, item];
      set({ types: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          const created = await createGovernanceDictionary('requirement_type', name);
          set({
            types: get().types.map((type) => (type.id === item.id ? governanceRowToDictItem(created) : type)),
            loaded: true,
          });
        },
        expected: updated,
        getCurrent: () => get().types,
        rollback: () => set({ types, loaded: true }),
      });
    },

    updateType: (id, name) => {
      const { types } = get();
      const updated = types.map((t) => (t.id === id ? { ...t, name } : t));
      set({ types: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await updateGovernanceDictionary('requirement_type', id, name);
        },
        expected: updated,
        getCurrent: () => get().types,
        rollback: () => set({ types, loaded: true }),
      });
    },

    deleteType: (id) => {
      const { types } = get();
      const updated = types.filter((t) => t.id !== id);
      set({ types: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await deleteGovernanceDictionary('requirement_type', id);
        },
        expected: updated,
        getCurrent: () => get().types,
        rollback: () => set({ types, loaded: true }),
      });
    },

    // --- Platform dict ---
    addPlatform: (name) => {
      const item: DictItem = { id: `platform-${Date.now()}`, name, createdAt: new Date().toISOString().slice(0, 10) };
      const { platforms } = get();
      const updated = [...platforms, item];
      set({ platforms: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          const created = await createGovernanceDictionary('requirement_platform', name);
          set({
            platforms: get().platforms.map((platform) => (platform.id === item.id ? governanceRowToDictItem(created) : platform)),
            loaded: true,
          });
        },
        expected: updated,
        getCurrent: () => get().platforms,
        rollback: () => set({ platforms, loaded: true }),
      });
    },

    updatePlatform: (id, name) => {
      const { platforms } = get();
      const updated = platforms.map((p) => (p.id === id ? { ...p, name } : p));
      set({ platforms: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await updateGovernanceDictionary('requirement_platform', id, name);
        },
        expected: updated,
        getCurrent: () => get().platforms,
        rollback: () => set({ platforms, loaded: true }),
      });
    },

    deletePlatform: (id) => {
      const { platforms } = get();
      const updated = platforms.filter((p) => p.id !== id);
      set({ platforms: updated, loaded: true });
      scheduleSaveWithOptimisticRollback({
        save: async () => {
          await deleteGovernanceDictionary('requirement_platform', id);
        },
        expected: updated,
        getCurrent: () => get().platforms,
        rollback: () => set({ platforms, loaded: true }),
      });
    },
  };
});

function hasDomainPatch(data: Partial<Requirement>) {
  return Object.values(data).some((value) => value !== undefined);
}

async function loadScopedRequirementsFromRelation(
  options?: { productId?: string; projectId?: string; versionId?: string },
): Promise<Requirement[]> {
  if (!options?.productId) return [];
  const items: Requirement[] = [];
  let cursor: string | undefined;
  do {
    const query: V22RequirementsQuery = {
      productId: options.productId,
      projectId: options.projectId,
      versionId: options.versionId,
      sort: 'created_at_desc',
      limit: 500,
      cursor,
    };
    const page = await loadV22RequirementsPage(query);
    items.push(...page.items);
    cursor = page.nextCursor;
  } while (cursor);
  return items;
}

function mergeRequirementsForScope(
  current: Requirement[],
  scope: { productId?: string; projectId?: string; versionId?: string } | undefined,
  scopedRequirements: Requirement[],
) {
  if (!scope?.productId) return current;
  return [
    ...current.filter((requirement) => !isRequirementInScope(requirement, scope)),
    ...scopedRequirements,
  ];
}

function isRequirementInScope(
  requirement: Requirement,
  scope: { productId?: string; projectId?: string; versionId?: string },
) {
  if (scope.versionId) return requirement.versionId === scope.versionId;
  if (scope.projectId) return requirement.productId === scope.productId && requirement.projectId === scope.projectId;
  return requirement.productId === scope.productId;
}

async function loadRequirementGovernanceDictionaries() {
  const [types, platforms, sourceTargets] = await Promise.all([
    listGovernanceDictionary('requirement_type'),
    listGovernanceDictionary('requirement_platform'),
    listGovernanceDictionary('requirement_source'),
  ]);
  return {
    types: types.length > 0 ? types.map(governanceRowToDictItem) : PRESET_TYPES,
    platforms: platforms.length > 0 ? platforms.map(governanceRowToDictItem) : PRESET_PLATFORMS,
    sourceTargets: sourceTargets.length > 0 ? sourceTargets.map((row) => governanceRowToSourceTarget(row)) : PRESET_SOURCE_TARGETS,
  };
}

function listGovernanceDictionary(kind: RequirementGovernanceKind) {
  return api.get<GovernanceDictionaryRow[]>(`/governance/dictionaries?kind=${kind}`);
}

function createGovernanceDictionary(kind: RequirementGovernanceKind, name: string, group?: string) {
  const { actorId, permissions } = getGovernanceActorContext();
  return api.post<GovernanceDictionaryRow>('/governance/dictionaries', { actorId, permissions, kind, name, group });
}

function updateGovernanceDictionary(kind: RequirementGovernanceKind, id: string, name: string, group?: string) {
  const { actorId, permissions } = getGovernanceActorContext();
  return api.patch<GovernanceDictionaryRow>(`/governance/dictionaries/${kind}/${id}`, { actorId, permissions, kind, name, group });
}

function deleteGovernanceDictionary(kind: RequirementGovernanceKind, id: string) {
  const { actorId, permissions } = getGovernanceActorContext();
  return api.deleteWithBody<GovernanceDictionaryRow>(`/governance/dictionaries/${kind}/${id}`, { actorId, permissions });
}

function getGovernanceActorContext() {
  const user = useAuthStore.getState().user;
  const role = useMemberStore.getState().roles.find((item) => item.id === user?.roleId);
  return { actorId: user?.id ?? '', permissions: role?.permissions ?? [] };
}

function governanceRowToDictItem(row: GovernanceDictionaryRow): DictItem {
  return {
    id: row.id,
    name: row.name,
    createdAt: normalizeGovernanceCreatedAt(row.createdAt),
  };
}

function governanceRowToSourceTarget(row: GovernanceDictionaryRow, fallbackSourceType?: SourceType): SourceTarget {
  return {
    id: row.id,
    name: row.name,
    sourceType: normalizeGovernanceSourceType(row.group, fallbackSourceType),
    createdAt: normalizeGovernanceCreatedAt(row.createdAt),
  };
}

function normalizeGovernanceCreatedAt(value?: string) {
  return value ? value.slice(0, 10) : new Date().toISOString().slice(0, 10);
}

function normalizeGovernanceSourceType(value?: string | null, fallback: SourceType = 'customer'): SourceType {
  return ['customer', 'internal', 'operation', 'aftersale', 'market', 'competitor', 'management'].includes(value ?? '')
    ? value as SourceType
    : fallback;
}