import type {
  KappaLoginPayload,
  KappaLoginResponse,
  KappaInitiative,
  KappaUserStory,
  KappaEpicDevelopment,
  KappaCreateEpicPayload,
  KappaLogbookMaster,
  KappaLogbookEntry,
  KappaPlanningMaster,
  KappaPlanningEntry,
  KappaBusinessRule,
  KappaRequirement,
  KappaEmployee,
  PaginatedResponse,
} from '@/types/kappa'

const BASE = '/api'

class KappaAPI {
  private token: string | null = null

  constructor() {
    this.token = localStorage.getItem('kappa_token')
  }

  private get headers(): Record<string, string> {
    const h: Record<string, string> = {
      'Content-Type': 'application/json',
    }
    if (this.token) {
      h['Authorization'] = `Bearer ${this.token}`
    }
    return h
  }

  private async request<T>(
    method: string,
    path: string,
    body?: unknown
  ): Promise<T> {
    const opts: RequestInit = {
      method,
      headers: this.headers,
    }
    if (body && method !== 'GET') {
      opts.body = JSON.stringify(body)
    }
    const res = await fetch(`${BASE}${path}`, opts)
    if (!res.ok) {
      const text = await res.text()
      throw new Error(`KAPPA ${method} ${path}: ${res.status} — ${text.slice(0, 200)}`)
    }
    return res.json()
  }

  // ─── Auth ────────────────────────────────────────────

  async login(payload: KappaLoginPayload): Promise<KappaLoginResponse> {
    const data = await this.request<KappaLoginResponse>(
      'POST',
      '/users/login/',
      payload
    )
    this.token = data.access || data.token || data.key || null
    if (this.token) {
      localStorage.setItem('kappa_token', this.token)
    }
    return data
  }

  logout() {
    this.token = null
    localStorage.removeItem('kappa_token')
  }

  get isAuthenticated(): boolean {
    return !!this.token
  }

  // ─── Proyectos (Initiatives) ─────────────────────────

  async getInitiatives(): Promise<KappaInitiative[]> {
    return this.request<KappaInitiative[]>('GET', '/initiatives-all/')
  }

  // ─── User Stories ────────────────────────────────────

  async createUserStory(story: KappaUserStory): Promise<KappaUserStory> {
    return this.request<KappaUserStory>('POST', '/userstorys/create/', story)
  }

  // ─── Users ───────────────────────────────────────────

  async getUsers(): Promise<unknown[]> {
    return this.request<unknown[]>('GET', '/users/all/')
  }

  async getEmployees(page = 1): Promise<PaginatedResponse<KappaEmployee>> {
    return this.request<PaginatedResponse<KappaEmployee>>('GET', `/employees/?page=${page}`)
  }

  async getUserStories(initiativeId?: number, page = 1, pageSize = 100): Promise<PaginatedResponse<KappaUserStory>> {
    const params = new URLSearchParams()
    if (initiativeId) params.set('initiative', String(initiativeId))
    params.set('page', String(page))
    params.set('page_size', String(pageSize))
    return this.request<PaginatedResponse<KappaUserStory>>('GET', `/userstorys/?${params.toString()}`)
  }

  async getAllUserStories(initiativeId: number): Promise<KappaUserStory[]> {
    const first = await this.getUserStories(initiativeId, 1, 100)
    const all = [...first.results]
    const totalPages = Math.ceil(first.count / 100)
    for (let p = 2; p <= totalPages; p++) {
      const page = await this.getUserStories(initiativeId, p, 100)
      all.push(...page.results)
    }
    return all
  }

  async getEpicDevelopment(initiativeId: number, page = 1, pageSize = 50): Promise<PaginatedResponse<KappaEpicDevelopment>> {
    return this.request<PaginatedResponse<KappaEpicDevelopment>>('GET', `/epicdevelopment/?initiative=${initiativeId}&page=${page}&page_size=${pageSize}`)
  }

  async getAllEpicDevelopment(initiativeId: number): Promise<KappaEpicDevelopment[]> {
    const first = await this.getEpicDevelopment(initiativeId, 1, 100)
    const all = [...first.results]
    const totalPages = Math.ceil(first.count / 100)
    for (let p = 2; p <= totalPages; p++) {
      const page = await this.getEpicDevelopment(initiativeId, p, 100)
      all.push(...page.results)
    }
    return all
  }

  async createEpicDevelopment(data: KappaCreateEpicPayload): Promise<KappaEpicDevelopment> {
    return this.request<KappaEpicDevelopment>('POST', '/epicdevelopment/create/', data)
  }

  async getLogbooks(initiativeId?: number): Promise<KappaLogbookEntry[]> {
    const path = initiativeId ? `/logbooks/?initiative=${initiativeId}` : '/logbooks/'
    return this.request<KappaLogbookEntry[]>('GET', path)
  }

  async getPlannings(initiativeId?: number): Promise<KappaPlanningEntry[]> {
    const path = initiativeId ? `/plannings/?initiative=${initiativeId}` : '/plannings/'
    return this.request<KappaPlanningEntry[]>('GET', path)
  }

  async getBusinessRules(initiativeId?: number): Promise<KappaBusinessRule[]> {
    const path = initiativeId ? `/business-rules/?initiative=${initiativeId}` : '/business-rules/'
    return this.request<KappaBusinessRule[]>('GET', path)
  }

  async getRequirements(initiativeId?: number): Promise<KappaRequirement[]> {
    const path = initiativeId ? `/functionalrequirements/?initiative=${initiativeId}` : '/functionalrequirements/'
    return this.request<KappaRequirement[]>('GET', path)
  }

  // ─── Bitácoras (Logbooks) ────────────────────────────

  async createLogbookMaster(data: KappaLogbookMaster): Promise<KappaLogbookMaster> {
    return this.request<KappaLogbookMaster>('POST', '/logbooks_master/create/', data)
  }

  async createLogbookEntry(data: KappaLogbookEntry): Promise<KappaLogbookEntry> {
    return this.request<KappaLogbookEntry>('POST', '/logbooks/create/', data)
  }

  // ─── Planeaciones (Plannings) ────────────────────────

  async createPlanningMaster(data: KappaPlanningMaster): Promise<KappaPlanningMaster> {
    return this.request<KappaPlanningMaster>('POST', '/plannings_master/create/', data)
  }

  async createPlanningEntry(data: KappaPlanningEntry): Promise<KappaPlanningEntry> {
    return this.request<KappaPlanningEntry>('POST', '/plannings/create/', data)
  }

  // ─── Business Rules ──────────────────────────────────

  async createBusinessRule(data: KappaBusinessRule): Promise<unknown> {
    return this.request<unknown>('POST', '/business-rules/create/', data)
  }

  // ─── Requisitos ──────────────────────────────────────

  async createRequirement(data: KappaRequirement): Promise<unknown> {
    return this.request<unknown>('POST', '/functionalrequirements/create/', data)
  }
}

export const kappa = new KappaAPI()