/**
 * Korrektur Archiv API - NiBiS Zentralabitur Documents and Stats
 *
 * Split from api.ts to stay under 500 LOC.
 */

import { getApiBase, apiFetch, getFairnessAnalysis, getKlausuren } from './api-core'

// ============================================================================
// ARCHIV API (NiBiS Zentralabitur Documents)
// ============================================================================

export interface ArchivDokument {
  id: string
  title: string
  subject: string
  niveau: string
  year: number
  task_number?: number
  doc_type: string
  variant?: string
  bundesland: string
  minio_path?: string
  preview_url?: string
}

export interface ArchivSearchResponse {
  total: number
  documents: ArchivDokument[]
  filters: {
    subjects: string[]
    years: number[]
    niveaus: string[]
    doc_types: string[]
  }
}

export interface ArchivFilters {
  subject?: string
  year?: number
  bundesland?: string
  niveau?: string
  doc_type?: string
  search?: string
  limit?: number
  offset?: number
}

export async function getArchivDocuments(filters: ArchivFilters = {}): Promise<ArchivSearchResponse> {
  const params = new URLSearchParams()
  if (filters.subject && filters.subject !== 'Alle') params.append('subject', filters.subject)
  if (filters.year) params.append('year', filters.year.toString())
  if (filters.bundesland && filters.bundesland !== 'Alle') params.append('bundesland', filters.bundesland)
  if (filters.niveau && filters.niveau !== 'Alle') params.append('niveau', filters.niveau)
  if (filters.doc_type && filters.doc_type !== 'Alle') params.append('doc_type', filters.doc_type)
  if (filters.search) params.append('search', filters.search)
  if (filters.limit) params.append('limit', filters.limit.toString())
  if (filters.offset) params.append('offset', filters.offset.toString())
  const queryString = params.toString()
  return apiFetch<ArchivSearchResponse>(`/api/v1/archiv${queryString ? `?${queryString}` : ''}`)
}

export async function getArchivDocument(docId: string): Promise<ArchivDokument & { text_preview?: string }> {
  return apiFetch<ArchivDokument & { text_preview?: string }>(`/api/v1/archiv/${docId}`)
}

export async function getArchivDocumentUrl(docId: string, expires: number = 3600): Promise<{ url: string; expires_in: number; filename: string }> {
  return apiFetch<{ url: string; expires_in: number; filename: string }>(`/api/v1/archiv/${docId}/url?expires=${expires}`)
}

export async function searchArchivSemantic(
  query: string,
  options: { year?: number; subject?: string; niveau?: string; limit?: number } = {}
): Promise<Array<{ id: string; score: number; text: string; year: number; subject: string; niveau: string; task_number?: number; doc_type: string }>> {
  const params = new URLSearchParams({ query })
  if (options.year) params.append('year', options.year.toString())
  if (options.subject) params.append('subject', options.subject)
  if (options.niveau) params.append('niveau', options.niveau)
  if (options.limit) params.append('limit', options.limit.toString())
  return apiFetch(`/api/v1/archiv/search/semantic?${params.toString()}`)
}

export async function getArchivSuggestions(query: string): Promise<Array<{ label: string; type: string }>> {
  return apiFetch<Array<{ label: string; type: string }>>(`/api/v1/archiv/suggest?query=${encodeURIComponent(query)}`)
}

export async function getArchivStats(): Promise<{
  total_documents: number; total_chunks: number;
  by_year: Record<string, number>; by_subject: Record<string, number>; by_niveau: Record<string, number>;
}> {
  return apiFetch('/api/v1/archiv/stats')
}

// ============================================================================
// STATS API (for Dashboard)
// ============================================================================

export interface KorrekturStats {
  totalKlausuren: number
  totalStudents: number
  openCorrections: number
  completedThisWeek: number
  averageGrade: number
  timeSavedHours: number
}

export async function getKorrekturStats(): Promise<KorrekturStats> {
  try {
    const klausuren = await getKlausuren()
    let totalStudents = 0, openCorrections = 0, completedCount = 0, gradeSum = 0, gradedCount = 0

    for (const klausur of klausuren) {
      totalStudents += klausur.student_count || 0
      completedCount += klausur.completed_count || 0
      openCorrections += (klausur.student_count || 0) - (klausur.completed_count || 0)
    }

    for (const klausur of klausuren) {
      if (klausur.status === 'completed' || klausur.status === 'in_progress') {
        try {
          const fairness = await getFairnessAnalysis(klausur.id)
          if (fairness.average_grade > 0) { gradeSum += fairness.average_grade; gradedCount++ }
        } catch { /* Skip */ }
      }
    }

    const averageGrade = gradedCount > 0 ? gradeSum / gradedCount : 0
    return {
      totalKlausuren: klausuren.length, totalStudents, openCorrections,
      completedThisWeek: completedCount,
      averageGrade: Math.round(averageGrade * 10) / 10,
      timeSavedHours: Math.round(completedCount * 0.5),
    }
  } catch {
    return { totalKlausuren: 0, totalStudents: 0, openCorrections: 0, completedThisWeek: 0, averageGrade: 0, timeSavedHours: 0 }
  }
}