import { useEffect, useState } from "react";
import { supabase } from "@/lib/supabase";
import type { ColorId, Status } from "@/data/lists";

export interface Project {
  id: string;
  nombre: string;
  color: ColorId;
  cliente: string;
  bu: string;
  cm: string; // autocompletado desde BU
  marca: string;
  solicitante: string;
  comentarios: string;
  briefLink: string;
  propuestaLinks: string[];
  afLinks: string[];
  status: Status | "";
  monto: number | null; // solo Marrero
  mes: string;
  anio: number;
  createdAt: number;
}

export type SheetSyncStatus = "synced" | "skipped" | "failed" | "timeout";

export type SaveProjectResult = {
  projectId: string;
  sheetSyncStatus: SheetSyncStatus;
  sheetSyncMessage: string;
};

type DbProjectLink = {
  id?: string;
  link_type: string | null;
  url: string | null;
  label?: string | null;
};

type DbProject = {
  id: string;
  title: string | null;
  client: string | null;
  brand: string | null;
  country: string | null;
  requested_by: string | null;
  country_manager: string | null;
  description: string | null;
  status: string | null;
  internal_amount?: number | string | null;
  brief_link: string | null;
  created_at: string | null;
  extra_data: Record<string, unknown> | null;
  project_links?: DbProjectLink[] | null;
};

const DEFAULT_COLOR: ColorId = "blue";
const OPEN_STATUS = "Activo";
const GERARDO_EMAIL = "gmarrero@gomezleemarketing.com";

let listeners: Array<() => void> = [];
let cache: Project[] = [];
let loading = false;
let initialized = false;
let errorMessage: string | null = null;
let projectsRealtimeChannel: ReturnType<typeof supabase.channel> | null = null;
let realtimeRefreshTimeout: ReturnType<typeof setTimeout> | null = null;
let activeHookInstances = 0;

function notify() {
  listeners.forEach((listener) => listener());
}

function asString(value: unknown, fallback = "") {
  return typeof value === "string" ? value : fallback;
}

function asNumber(value: unknown, fallback: number) {
  return typeof value === "number" && Number.isFinite(value) ? value : fallback;
}

function toUiStatus(status: string | null | undefined): Status | "" {
  // En base de datos usamos "Activo" para proyectos abiertos.
  // En la UI histórica, proyecto abierto = status vacío.
  if (!status || status === OPEN_STATUS) return "";
  return status as Status;
}

function toDbStatus(status: Status | "" | undefined | null): string {
  return status && status.trim() ? status : OPEN_STATUS;
}

function mapDbProject(row: DbProject): Project {
  const extra = row.extra_data || {};
  const links = row.project_links || [];
  const propuestaLinks = links
    .filter((link) => link.link_type === "proposal")
    .map((link) => link.url || "")
    .filter(Boolean);
  const afLinks = links
    .filter((link) => link.link_type === "final_art")
    .map((link) => link.url || "")
    .filter(Boolean);

  const createdAt = row.created_at ? new Date(row.created_at).getTime() : Date.now();
  const date = Number.isFinite(createdAt) ? new Date(createdAt) : new Date();

  return {
    id: row.id,
    nombre: row.title || "",
    color: asString(extra.color, DEFAULT_COLOR) as ColorId,
    cliente: row.client || "",
    bu: row.country || "",
    cm: row.country_manager || "",
    marca: row.brand || "",
    solicitante: row.requested_by || "",
    comentarios: row.description || "",
    briefLink: row.brief_link || "",
    propuestaLinks,
    afLinks,
    status: toUiStatus(row.status),
    monto: row.internal_amount == null ? null : Number(row.internal_amount),
    mes: asString(extra.mes, "") || date.toLocaleString("es-DO", { month: "long" }),
    anio: asNumber(extra.anio, date.getFullYear()),
    createdAt: Number.isFinite(createdAt) ? createdAt : Date.now(),
  };
}

async function getCurrentUser() {
  const { data, error } = await supabase.auth.getUser();

  if (error || !data.user) {
    throw new Error("No hay una sesión activa de Supabase.");
  }

  return data.user;
}

async function getCurrentUserId(): Promise<string> {
  const user = await getCurrentUser();
  return user.id;
}

async function currentUserIsGerardo(): Promise<boolean> {
  const user = await getCurrentUser();
  return user.email?.toLowerCase() === GERARDO_EMAIL;
}

function toProjectRow(project: Omit<Project, "id" | "createdAt"> | Partial<Project>) {
  return {
    title: project.nombre,
    client: project.cliente,
    brand: project.marca,
    country: project.bu,
    requested_by: project.solicitante,
    country_manager: project.cm,
    description: project.comentarios,
    status: toDbStatus(project.status),
    internal_amount: project.monto ?? null,
    brief_link: project.briefLink,
    extra_data: {
      color: project.color ?? DEFAULT_COLOR,
      mes: project.mes,
      anio: project.anio,
    },
  };
}

function toLinkRows(projectId: string, project: Pick<Project, "propuestaLinks" | "afLinks">) {
  const proposalLinks = project.propuestaLinks
    .map((url) => url.trim())
    .filter(Boolean)
    .map((url, index) => ({
      project_id: projectId,
      link_type: "proposal",
      url,
      label: `Propuesta ${index + 1}`,
    }));

  const finalArtLinks = project.afLinks
    .map((url) => url.trim())
    .filter(Boolean)
    .map((url, index) => ({
      project_id: projectId,
      link_type: "final_art",
      url,
      label: `AF ${index + 1}`,
    }));

  return [...proposalLinks, ...finalArtLinks];
}

function setCache(next: Project[]) {
  cache = next;
  notify();
}

function setError(message: string | null) {
  errorMessage = message;
  notify();
}


function getSyncWebhookUrl() {
  return import.meta.env.VITE_WEBHOOK_URL?.trim() || "";
}

async function syncProjectToSheet(
  projectId: string,
  action: "create" | "update",
): Promise<Omit<SaveProjectResult, "projectId">> {
  const webhookUrl = getSyncWebhookUrl();

  if (!webhookUrl) {
    console.info("No se configuró VITE_WEBHOOK_URL; se omite sincronización con Google Sheet.");
    return {
      sheetSyncStatus: "skipped",
      sheetSyncMessage: "Proyecto guardado. No hay webhook configurado para sincronizar el Sheet.",
    };
  }

  const controller = new AbortController();
  const timeout = window.setTimeout(() => controller.abort(), 15000);

  try {
    const response = await fetch(webhookUrl, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
      },
      body: JSON.stringify({
        project_id: projectId,
        action,
        source: "tablero-cdc",
        sent_at: new Date().toISOString(),
      }),
      signal: controller.signal,
    });

    if (!response.ok) {
      const errorText = await response.text().catch(() => "");
      const message = errorText || `${response.status} ${response.statusText}`.trim();

      console.warn("El proyecto se guardó en Supabase, pero n8n no respondió correctamente.", {
        status: response.status,
        statusText: response.statusText,
        errorText,
      });

      return {
        sheetSyncStatus: "failed",
        sheetSyncMessage: `Proyecto guardado, pero el Sheet no se pudo sincronizar: ${message}`,
      };
    }

    return {
      sheetSyncStatus: "synced",
      sheetSyncMessage: "Proyecto guardado y sincronizado con el Google Sheet.",
    };
  } catch (error) {
    const isTimeout = error instanceof DOMException && error.name === "AbortError";

    console.warn("El proyecto se guardó en Supabase, pero no se pudo sincronizar con Google Sheet.", error);

    return {
      sheetSyncStatus: isTimeout ? "timeout" : "failed",
      sheetSyncMessage: isTimeout
        ? "Proyecto guardado, pero n8n tardó demasiado en responder. Revisa el workflow si el Sheet no se actualizó."
        : "Proyecto guardado, pero no se pudo sincronizar con Google Sheet.",
    };
  } finally {
    window.clearTimeout(timeout);
  }
}

function scheduleRealtimeRefresh() {
  if (realtimeRefreshTimeout) {
    clearTimeout(realtimeRefreshTimeout);
  }

  realtimeRefreshTimeout = setTimeout(() => {
    realtimeRefreshTimeout = null;

    if (!loading) {
      void loadProjects();
    }
  }, 350);
}

function startProjectsRealtime() {
  if (projectsRealtimeChannel) return;

  projectsRealtimeChannel = supabase
    .channel("tablero-cdc-projects")
    .on(
      "postgres_changes",
      { event: "*", schema: "public", table: "tablero_cdc_projects" },
      () => scheduleRealtimeRefresh(),
    )
    .on(
      "postgres_changes",
      { event: "*", schema: "public", table: "tablero_cdc_project_links" },
      () => scheduleRealtimeRefresh(),
    )
    .subscribe((status) => {
      if (status === "CHANNEL_ERROR" || status === "TIMED_OUT") {
        console.warn("Supabase Realtime no pudo suscribirse a proyectos:", status);
      }
    });
}

function stopProjectsRealtime() {
  if (realtimeRefreshTimeout) {
    clearTimeout(realtimeRefreshTimeout);
    realtimeRefreshTimeout = null;
  }

  if (!projectsRealtimeChannel) return;

  void supabase.removeChannel(projectsRealtimeChannel);
  projectsRealtimeChannel = null;
}

async function replaceProjectLinks(projectId: string, project: Pick<Project, "propuestaLinks" | "afLinks">) {
  const { error: deleteError } = await supabase
    .from("tablero_cdc_project_links")
    .delete()
    .eq("project_id", projectId);

  if (deleteError) throw deleteError;

  const linkRows = toLinkRows(projectId, project);

  if (linkRows.length === 0) return;

  const { error: insertError } = await supabase.from("tablero_cdc_project_links").insert(linkRows);

  if (insertError) throw insertError;
}

async function loadProjects() {
  loading = true;
  setError(null);
  notify();

  try {
    const isGerardo = await currentUserIsGerardo();
    const selectColumns = `
        id,
        title,
        client,
        brand,
        country,
        requested_by,
        country_manager,
        description,
        status,
        ${isGerardo ? "internal_amount," : ""}
        brief_link,
        created_at,
        extra_data,
        project_links:tablero_cdc_project_links (
          id,
          link_type,
          url,
          label
        )
      `;

    const { data, error } = await supabase
      .from("tablero_cdc_projects")
      .select(selectColumns)
      .order("created_at", { ascending: false });

    if (error) throw error;

    cache = (data || []).map((row) => mapDbProject(row as unknown as DbProject));
    initialized = true;
  } catch (error) {
    console.error("Error cargando proyectos desde Supabase:", error);
    errorMessage =
      error instanceof Error
        ? error.message
        : "No se pudieron cargar los proyectos desde Supabase.";
  } finally {
    loading = false;
    notify();
  }
}

async function addProject(project: Project) {
  setError(null);

  const userId = await getCurrentUserId();
  const insertPayload = {
    ...toProjectRow(project),
    created_by: userId,
    updated_by: userId,
  };

  const { data, error } = await supabase
    .from("tablero_cdc_projects")
    .insert(insertPayload)
    .select("id")
    .single();

  if (error) {
    setError(error.message);
    throw error;
  }

  await replaceProjectLinks(data.id, project);
  const sheetSync = await syncProjectToSheet(data.id, "create");
  await loadProjects();

  return {
    projectId: data.id,
    ...sheetSync,
  } satisfies SaveProjectResult;
}

async function updateProject(id: string, patch: Partial<Project>) {
  setError(null);

  const userId = await getCurrentUserId();
  const isGerardo = await currentUserIsGerardo();
  const current = cache.find((project) => project.id === id);
  const nextProject = current ? { ...current, ...patch } : ({ ...patch, id } as Project);

  const rowPayload = toProjectRow(nextProject);
  const updatePayload = isGerardo
    ? {
      ...rowPayload,
      updated_by: userId,
    }
    : {
      title: rowPayload.title,
      client: rowPayload.client,
      brand: rowPayload.brand,
      country: rowPayload.country,
      requested_by: rowPayload.requested_by,
      country_manager: rowPayload.country_manager,
      description: rowPayload.description,
      status: rowPayload.status,
      brief_link: rowPayload.brief_link,
      extra_data: rowPayload.extra_data,
      updated_by: userId,
    };

  const { error } = await supabase.from("tablero_cdc_projects").update(updatePayload).eq("id", id);

  if (error) {
    setError(error.message);
    throw error;
  }

  await replaceProjectLinks(id, nextProject);
  const sheetSync = await syncProjectToSheet(id, "update");
  await loadProjects();

  return {
    projectId: id,
    ...sheetSync,
  } satisfies SaveProjectResult;
}


export function useProjects() {
  const [, force] = useState(0);

  useEffect(() => {
    const listener = () => force((n) => n + 1);
    listeners.push(listener);
    activeHookInstances += 1;

    startProjectsRealtime();

    if (!initialized && !loading) {
      void loadProjects();
    }

    return () => {
      listeners = listeners.filter((x) => x !== listener);
      activeHookInstances = Math.max(0, activeHookInstances - 1);

      if (activeHookInstances === 0) {
        stopProjectsRealtime();
      }
    };
  }, []);

  return {
    projects: cache,
    loading,
    error: errorMessage,
    refresh: loadProjects,
    add: addProject,
    update: updateProject,
  };
}

// NOTE: useRole() was removed in favour of useAuth() from AuthContext.
// Role logic (isGerardo) is now derived from the real Supabase authenticated user.