"use server";

import { createAdminClient } from "@/lib/supabase/server";
import { auth } from "@clerk/nextjs/server";
import type {
  PositionWithRelations,
  Applicant,
  CreatePositionInput,
  UpdatePositionInput,
  CreateApplicantInput,
} from "./recruitment-types";

// ── Helpers ──────────────────────────────────────────────────

async function getOrgAndUserId(): Promise<{ orgId: string; userId: string }> {
  const { userId } = await auth();
  if (!userId) throw new Error("Unauthenticated");
  const supabase = await createAdminClient();
  const { data } = await supabase
    .from("organisation_members")
    .select("organisation_id, role")
    .eq("user_id", userId)
    .single();
  if (!data) throw new Error("No org found");
  return { orgId: data.organisation_id, userId };
}

// ── Open Positions ──────────────────────────────────────────

export async function fetchPositions(): Promise<PositionWithRelations[]> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { data } = await supabase
    .from("job_postings")
    .select(
      `
      *,
      department:departments(name),
      applicants:applicants(count)
    `
    )
    .eq("organisation_id", orgId)
    .order("created_at", { ascending: false });

  return (data || []).map((jp: PositionWithRelations & { applicants: { count: number }[] }) => ({
    ...jp,
    applicant_count: jp.applicants?.[0]?.count || 0,
  }));
}

export async function createPosition(
  input: CreatePositionInput
): Promise<{ success: boolean; id?: string; error?: string }> {
  const { orgId, userId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { data, error } = await supabase
    .from("job_postings")
    .insert({
      ...input,
      organisation_id: orgId,
      created_by: userId,
    })
    .select("id")
    .single();
  if (error) return { success: false, error: error.message };
  return { success: true, id: data.id };
}

export async function updatePosition(
  id: string,
  input: UpdatePositionInput
): Promise<{ success: boolean; error?: string }> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { error } = await supabase
    .from("job_postings")
    .update(input)
    .eq("id", id)
    .eq("organisation_id", orgId);
  if (error) return { success: false, error: error.message };
  return { success: true };
}

export async function fetchPosition(id: string): Promise<PositionWithRelations | null> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { data } = await supabase
    .from("job_postings")
    .select(
      `
      *,
      department:departments(name),
      applicants:applicants(count)
    `
    )
    .eq("id", id)
    .eq("organisation_id", orgId)
    .single();

  if (!data) return null;
  return {
    ...data,
    applicant_count: data.applicants?.[0]?.count || 0,
  };
}

// ── Applicants ───────────────────────────────────────────────

export async function fetchApplicants(positionId: string): Promise<Applicant[]> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { data } = await supabase
    .from("applicants")
    .select("*")
    .eq("organisation_id", orgId)
    .eq("job_posting_id", positionId)
    .order("created_at", { ascending: false });
  return data || [];
}

export async function createApplicant(
  input: CreateApplicantInput
): Promise<{ success: boolean; error?: string }> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { error } = await supabase
    .from("applicants")
    .insert({ ...input, organisation_id: orgId });
  if (error) return { success: false, error: error.message };
  return { success: true };
}

export async function updateApplicantStage(
  id: string,
  stage: string
): Promise<{ success: boolean; error?: string }> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { error } = await supabase
    .from("applicants")
    .update({ stage })
    .eq("id", id)
    .eq("organisation_id", orgId);
  if (error) return { success: false, error: error.message };
  return { success: true };
}

export async function updateApplicantNotes(
  id: string,
  notes: string
): Promise<{ success: boolean; error?: string }> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { error } = await supabase
    .from("applicants")
    .update({ notes })
    .eq("id", id)
    .eq("organisation_id", orgId);
  if (error) return { success: false, error: error.message };
  return { success: true };
}

export async function deleteApplicant(
  id: string
): Promise<{ success: boolean; error?: string }> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { error } = await supabase
    .from("applicants")
    .delete()
    .eq("id", id)
    .eq("organisation_id", orgId);
  if (error) return { success: false, error: error.message };
  return { success: true };
}

// ── Resume Upload ────────────────────────────────────────────

export async function uploadResume(
  file: File
): Promise<{ success: boolean; url?: string; error?: string }> {
  const { orgId, userId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const ext = file.name.split(".").pop();
  const filePath = `${orgId}/${userId}/${Date.now()}-resume.${ext}`;
  const { error: uploadError } = await supabase.storage
    .from("resumes")
    .upload(filePath, file);
  if (uploadError) return { success: false, error: uploadError.message };
  const { data } = await supabase.storage
    .from("resumes")
    .createSignedUrl(filePath, 86400 * 365);
  return { success: true, url: data?.signedUrl };
}

// ── Departments ──────────────────────────────────────────────

export async function fetchDepartments(): Promise<{ id: string; name: string }[]> {
  const { orgId } = await getOrgAndUserId();
  const supabase = await createAdminClient();
  const { data } = await supabase
    .from("departments")
    .select("id, name")
    .eq("organisation_id", orgId)
    .order("name", { ascending: true });
  return data || [];
}