import type { SupabaseClient } from "@supabase/supabase-js";
import { defaultLeagueRules } from "@/lib/rules/schema";
import { slugify } from "@/lib/utils";

export async function deleteLeague(supabase: SupabaseClient, leagueId: string) {
  const { error } = await supabase.from("leagues").delete().eq("id", leagueId);
  if (error) throw new Error(error.message);
}

export async function listLeaguesForMaster(
  supabase: SupabaseClient,
  userId: string,
  isGlobalMaster: boolean
) {
  if (isGlobalMaster) return listLeagues(supabase);

  const { data: owned } = await supabase
    .from("leagues")
    .select("*")
    .eq("created_by", userId);

  const { data: assigned } = await supabase
    .from("league_masters")
    .select("leagues(*)")
    .eq("user_id", userId);

  type LeagueRow = Awaited<ReturnType<typeof listLeagues>>[number];
  const merged: LeagueRow[] = [
    ...(owned ?? []),
    ...((assigned ?? [])
      .map((a) => a.leagues as LeagueRow | null)
      .filter(Boolean) as LeagueRow[]),
  ];
  return Array.from(new Map(merged.map((l) => [l.id, l])).values()).sort(
    (a, b) =>
      new Date(b.created_at).getTime() - new Date(a.created_at).getTime()
  );
}

export async function listLeagues(supabase: SupabaseClient) {
  const { data, error } = await supabase
    .from("leagues")
    .select("*")
    .order("created_at", { ascending: false });
  if (error) throw new Error(error.message);
  return data;
}

export async function createLeague(
  supabase: SupabaseClient,
  userId: string,
  input: { name: string; description?: string }
) {
  const { data: league, error } = await supabase
    .from("leagues")
    .insert({
      name: input.name,
      slug: slugify(input.name) + "-" + Date.now().toString(36),
      description: input.description || null,
      created_by: userId,
    })
    .select()
    .single();

  if (error) throw new Error(error.message);

  await supabase.from("league_rules").insert({
    league_id: league.id,
    version: 1,
    rules: defaultLeagueRules,
    created_by: userId,
  });

  return league;
}

export async function getLeague(supabase: SupabaseClient, leagueId: string) {
  const { data, error } = await supabase
    .from("leagues")
    .select("*, competitions(*)")
    .eq("id", leagueId)
    .single();
  if (error) throw new Error(error.message);
  return data;
}

export async function createCompetition(
  supabase: SupabaseClient,
  userId: string,
  leagueId: string,
  input: {
    name: string;
    tournament_mode: "league" | "cup";
    timezone?: string;
  }
) {
  const { data, error } = await supabase
    .from("competitions")
    .insert({
      league_id: leagueId,
      name: input.name,
      tournament_mode: input.tournament_mode,
      timezone: input.timezone || "UTC",
      created_by: userId,
    })
    .select()
    .single();
  if (error) throw new Error(error.message);
  return data;
}

export async function getCompetition(
  supabase: SupabaseClient,
  competitionId: string
) {
  const { data, error } = await supabase
    .from("competitions")
    .select("*, leagues(id, name)")
    .eq("id", competitionId)
    .single();
  if (error) throw new Error(error.message);
  return data;
}

export async function activateCompetition(
  supabase: SupabaseClient,
  competitionId: string
) {
  const { error } = await supabase.rpc("activate_competition", {
    p_competition_id: competitionId,
  });
  if (error) throw new Error(error.message);
}

export async function generateFixtures(
  supabase: SupabaseClient,
  competitionId: string,
  mode: "league" | "cup"
) {
  const fn = mode === "cup" ? "generate_cup_bracket" : "generate_league_fixtures";
  const { data, error } = await supabase.rpc(fn, {
    p_competition_id: competitionId,
  });
  if (error) throw new Error(error.message);
  return data;
}

export async function getStandings(
  supabase: SupabaseClient,
  competitionId: string
) {
  const { data, error } = await supabase
    .from("competition_standings")
    .select("*")
    .eq("competition_id", competitionId);
  if (error) throw new Error(error.message);
  return data;
}

export async function saveLeagueRules(
  supabase: SupabaseClient,
  userId: string,
  leagueId: string,
  rules: object
) {
  const { data: latest } = await supabase
    .from("league_rules")
    .select("version")
    .eq("league_id", leagueId)
    .order("version", { ascending: false })
    .limit(1)
    .single();

  const { error } = await supabase.from("league_rules").insert({
    league_id: leagueId,
    version: (latest?.version ?? 0) + 1,
    rules,
    created_by: userId,
  });
  if (error) throw new Error(error.message);
}