'use server'

import { revalidatePath } from 'next/cache'
import { redirect } from 'next/navigation'
import { z } from 'zod'
import { requireUser } from '@/lib/auth/current'
import { AccessError, ConflictError } from '@/lib/errors'
import {
  createDocument,
  finalizeDocument,
  reclassifyDocument,
  retractDocument,
  saveDocumentSection,
  type Owner,
} from '@/lib/documents/service'
import { de } from '@/lib/i18n/de'
import type { SaveSectionResult } from '@/components/sections/types'

export type ActionResult = { ok: true } | { ok: false; error: string }

function toMessage(error: unknown): string {
  if (error instanceof AccessError) {
    return de.actionErrors[error.code] ?? de.actionErrors.default!
  }
  console.error('[dokumente] unerwartet', error)
  return de.actionErrors.default!
}

const createSchema = z.object({
  templateKey: z.string().min(1),
  title: z.string().max(200).optional(),
  classification: z.coerce.number().int().min(0).max(5),
  caseNumber: z.string().max(60).optional(),
  personnelFileId: z.string().max(64).optional(),
})

export async function createDocumentAction(
  _prev: ActionResult | null,
  formData: FormData,
): Promise<ActionResult> {
  const user = await requireUser()
  const parsed = createSchema.safeParse(Object.fromEntries(formData))
  if (!parsed.success) return { ok: false, error: de.actionErrors.default! }

  const owner: Owner = parsed.data.caseNumber
    ? { kind: 'case', caseNumber: parsed.data.caseNumber }
    : parsed.data.personnelFileId
      ? { kind: 'personnel', personnelFileId: parsed.data.personnelFileId }
      : { kind: 'standalone' }

  let documentNumber: string
  try {
    const created = await createDocument(user.permissions, {
      templateKey: parsed.data.templateKey,
      title: parsed.data.title,
      classification: parsed.data.classification,
      owner,
    })
    documentNumber = created.documentNumber
  } catch (error) {
    return { ok: false, error: toMessage(error) }
  }

  redirect(`/dokumente/${documentNumber}`)
}

const sectionSchema = z.object({
  fieldKey: z.string().min(1),
  value: z.unknown(),
  baseVersion: z.coerce.number().int().min(0),
  minClearance: z.coerce.number().int().min(0).max(5).optional(),
})

/** Das Dokument kommt gebunden herein, siehe `.bind`. */
export async function saveDocumentSectionAction(
  documentNumber: string,
  input: unknown,
): Promise<SaveSectionResult> {
  const user = await requireUser()
  const parsed = sectionSchema.safeParse(input)
  if (!parsed.success) return { ok: false, conflict: false, error: de.actionErrors.default! }

  try {
    const { version } = await saveDocumentSection(user.permissions, {
      documentNumber,
      ...parsed.data,
    })
    revalidatePath(`/dokumente/${documentNumber}`)
    return { ok: true, version }
  } catch (error) {
    if (error instanceof ConflictError) {
      return {
        ok: false,
        conflict: true,
        current: { value: error.current.value, version: error.current.version },
      }
    }
    return { ok: false, conflict: false, error: toMessage(error) }
  }
}

const numberSchema = z.object({ documentNumber: z.string().min(1) })

export async function finalizeDocumentAction(input: unknown): Promise<ActionResult> {
  const user = await requireUser()
  const parsed = numberSchema.safeParse(input)
  if (!parsed.success) return { ok: false, error: de.actionErrors.default! }

  try {
    await finalizeDocument(user.permissions, parsed.data.documentNumber)
    revalidatePath(`/dokumente/${parsed.data.documentNumber}`)
    return { ok: true }
  } catch (error) {
    return { ok: false, error: toMessage(error) }
  }
}

const retractSchema = numberSchema.extend({ reason: z.string().min(10).max(2000) })

export async function retractDocumentAction(input: unknown): Promise<ActionResult> {
  const user = await requireUser()
  const parsed = retractSchema.safeParse(input)
  if (!parsed.success) return { ok: false, error: de.actionErrors['reason-required']! }

  try {
    await retractDocument(user.permissions, parsed.data.documentNumber, parsed.data.reason)
    revalidatePath(`/dokumente/${parsed.data.documentNumber}`)
    return { ok: true }
  } catch (error) {
    return { ok: false, error: toMessage(error) }
  }
}

const reclassifySchema = numberSchema.extend({
  to: z.coerce.number().int().min(0).max(5),
  reason: z.string().max(2000).optional(),
})

export async function reclassifyDocumentAction(input: unknown): Promise<ActionResult> {
  const user = await requireUser()
  const parsed = reclassifySchema.safeParse(input)
  if (!parsed.success) return { ok: false, error: de.actionErrors.default! }

  try {
    await reclassifyDocument(
      user.permissions,
      parsed.data.documentNumber,
      parsed.data.to,
      parsed.data.reason,
    )
    revalidatePath(`/dokumente/${parsed.data.documentNumber}`)
    return { ok: true }
  } catch (error) {
    return { ok: false, error: toMessage(error) }
  }
}