// controllers/admin/advertisements.controller.js

const sequelize = require("../../config/db.config");
const Advertisement = require("../../models/advertisements/advertisements.mdl");
const mdl_Assets = require("../../models/assets/assets.mdl");
const mdl_Users = require('../../models/users/users.mdl');
const mediaToken = require("../../services/mediaToken.service");
const R = require('../../utils/response.util');
const { paginate } = require("../../utils/paginate.util");
const { adminExclude, jsonbSchemas, computedAttributes } = require("../../models/advertisements/advertisements.attributes");
const { PLACEMENT_MAP, PLACEMENT_KEYS } = require("../../models/advertisements/advertisements.placements");
const { getFieldValues } = require("../../utils/fieldValues.util");
const logActivity = require('../../utils/logActivity.util');

const { Op } = require('sequelize');

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

const notDeleted = { deletedAt: null };

const ALLOWED_STATUSES = ["draft", "active", "scheduled", "expired", "archived"];

// Fields needed off the associated Asset to render a preview AND (for S3 assets)
// mint a stream token — storage_key is stripped again in attachImageStreamToken
// before the row is ever sent out.
const AD_IMAGE_ATTRIBUTES = ["asset_id", "display_name", "file_url", "thumbnail_url", "storage_provider", "storage_key", "file_type", "mime_type"];

// ─── Media proxying ─────────────────────────────────────────────────────────
// Mirrors controllers/admin/assets.controller.js's redactS3Url/attachStreamTokens.
// Private (S3-backed) advertisement images must never expose a raw file_url to
// the browser — mint a short-lived stream token instead so the frontend resolves
// it through GET /api/client/media/stream/:token. Public/chibisafe images keep
// their direct file_url (no proxy needed).
async function attachImageStreamToken(image, req) {
  if (!image || image.storage_provider !== "s3" || !mediaToken.SUPPORTED_TYPES.includes(image.file_type)) {
    return image;
  }
  const ip = mediaToken.resolveIp(req);
  const { token } = await mediaToken.issueForAsset(image, req.user?.user_id, ip);
  image.stream_token = token;
  image.file_url = null;
  image.thumbnail_url = null;
  delete image.storage_key;
  return image;
}

// ─── Status derivation ─────────────────────────────────────────────────────
// status is never trusted as manually-set truth — it's derived from is_active
// + start_date/end_date every time an advertisement is read or written.
// "archived" is the only status that bypasses derivation (set by archive/restore).
function deriveStatus(advertisement) {
  if (advertisement.deletedAt) return "archived";
  if (!advertisement.is_active) return "draft";

  const now   = new Date();
  const start = advertisement.start_date ? new Date(advertisement.start_date) : null;
  const end   = advertisement.end_date   ? new Date(advertisement.end_date)   : null;

  if (end && end < now) return "expired";
  if (start && start > now) return "scheduled";
  return "active";
}

function normalizeCtas(ctas) {
  if (!Array.isArray(ctas)) return [];
  return ctas
    .filter((c) => c && typeof c.label === "string" && typeof c.link === "string")
    .slice(0, 2) // hard cap: max 2 CTAs per advertisement
    .map((c, i) => ({
      label:   c.label.trim(),
      link:    c.link.trim(),
      // Variant is always derived from position — first CTA is "default"
      // (primary), second is "outline" — not user-selectable, so any
      // client-sent variant is ignored.
      variant: i === 0 ? "default" : "outline",
    }));
}

// Hard cap: max 2 badge labels per advertisement (matches MAX_BADGE_LABELS on the frontend)
function normalizeBadgeLabels(labels) {
  if (!Array.isArray(labels)) return [];
  return labels
    .filter((l) => typeof l === "string" && l.trim().length > 0)
    .map((l) => l.trim())
    .slice(0, 2);
}

async function applyAdvertisementFields(advertisement, body) {
  // placement is the only settable "where" — type/format is always derived
  // from the placement's registry entry, never accepted directly from the body.
  if (body.placement !== undefined) {
    const entry = PLACEMENT_MAP[body.placement];
    if (!entry) {
      const err = new Error(`Invalid placement. Must be one of: ${PLACEMENT_KEYS.join(", ")}`);
      err.status = 400;
      throw err;
    }
    advertisement.placement = body.placement;
    advertisement.type = entry.format;
  }

  // status is intentionally NOT settable here — it's derived via deriveStatus()
  // right before save, based on is_active + start_date/end_date.

  // content_mode is no longer an admin choice (the Image Only / Text with
  // Image toggle was removed — every ad now carries the same mandatory
  // badge/headline/description/image/link shape) — like type/format, it's
  // fixed server-side rather than trusted from the request body. Legacy
  // "image" mode rows keep that value until next edited.
  advertisement.content_mode = "content";

  if (body.badge_labels !== undefined) advertisement.badge_labels = normalizeBadgeLabels(body.badge_labels);
  if (body.headline     !== undefined) advertisement.headline     = body.headline;
  if (body.description  !== undefined) advertisement.description  = body.description;
  if (body.image_url    !== undefined) advertisement.image_url    = body.image_url;
  if (body.redirect_link !== undefined) advertisement.redirect_link = body.redirect_link || null;
  if (body.landing_page  !== undefined) advertisement.landing_page  = body.landing_page  || null;

  if (body.image_asset_id !== undefined) {
    if (body.image_asset_id === null) {
      advertisement.image_asset_id = null;
    } else {
      const asset = await mdl_Assets.findOne({ where: { asset_id: body.image_asset_id, deletedAt: null } });
      if (!asset) {
        const err = new Error("Selected image asset was not found.");
        err.status = 400;
        throw err;
      }
      advertisement.image_asset_id = asset.asset_id;
    }
  }

  if (body.ctas !== undefined) advertisement.ctas = normalizeCtas(body.ctas);

  if (body.start_date !== undefined) advertisement.start_date = body.start_date || null;
  if (body.end_date   !== undefined) advertisement.end_date   = body.end_date   || null;

  if (body.order      !== undefined) advertisement.order      = parseInt(body.order) || 0;
  if (body.is_active  !== undefined) advertisement.is_active  = body.is_active === true || body.is_active === "true";

  if (body.size !== undefined) {
    if (body.size !== null && !["sm", "md", "lg", "xl"].includes(body.size)) {
      const err = new Error(`Invalid size. Must be one of: sm, md, lg, xl`);
      err.status = 400;
      throw err;
    }
    advertisement.size = body.size || null;
  }

  // Every ad now carries the same mandatory shape — badge label(s), headline,
  // description, image, and a single link — enforced here as defense-in-depth
  // alongside the frontend's Zod schema. The Admin Add/Edit Advertisement
  // forms always submit the full shape, so this only ever fires on malformed
  // requests — it does not retroactively touch existing incomplete rows,
  // it just blocks saving one until it's brought up to the new shape.
  if (!advertisement.badge_labels?.length) {
    const err = new Error("At least one badge label is required.");
    err.status = 400;
    throw err;
  }
  if (!advertisement.headline?.trim()) {
    const err = new Error("Headline is required.");
    err.status = 400;
    throw err;
  }
  if (!advertisement.description?.trim()) {
    const err = new Error("Description is required.");
    err.status = 400;
    throw err;
  }
  if (!advertisement.image_asset_id) {
    const err = new Error("Image is required.");
    err.status = 400;
    throw err;
  }
  if (!advertisement.redirect_link?.trim()) {
    const err = new Error("Link is required.");
    err.status = 400;
    throw err;
  }

  // Recompute status now that is_active/start_date/end_date are all up to date
  advertisement.status = deriveStatus(advertisement);
}

// ─── GET ALL ──────────────────────────────────────────────────────────────────

// Keeps the stored `status` column in sync with deriveStatus() before the
// filtered query runs — status is otherwise only recomputed on individual
// row reads, so filtering by status (e.g. "expired") would miss rows whose
// start_date/end_date lapsed since they were last saved.
async function syncDerivedStatuses() {
  await sequelize.query(`
    UPDATE advertisements
    SET status = CASE
      WHEN is_active = false THEN 'draft'
      WHEN end_date IS NOT NULL AND end_date < NOW() THEN 'expired'
      WHEN start_date IS NOT NULL AND start_date > NOW() THEN 'scheduled'
      ELSE 'active'
    END
    WHERE "deletedAt" IS NULL
  `);
}

exports.getAdvertisements = async (req, res) => {
  try {
    await syncDerivedStatuses();

    const result = await paginate(Advertisement, req, {
      excludeAttributes: adminExclude,
      jsonbSchemas,
      computedAttributes,
      context: "list",
      auditOptions: { mdl_Users, parentAlias: 'Advertisement' },
      findOptions: {
        where: { ...notDeleted },
        include: [{
          model:     mdl_Assets,
          as:        "image",
          attributes: AD_IMAGE_ATTRIBUTES,
          required:  false,
        }],
      },
    });

    // Resync status on the way out — never trust what's stored, since
    // start_date/end_date may have lapsed since the row was last saved.
    if (Array.isArray(result?.data)) {
      result.data = await Promise.all(result.data.map(async (row) => {
        if (row.image) await attachImageStreamToken(row.image, req);
        return { ...row, status: deriveStatus(row) };
      }));
    }

    return R.success(res, "Advertisements retrieved.", result);
  } catch (err) {
    console.error("[ADVERTISEMENT][GET ALL]", err);
    return R.error(res, "Could not retrieve advertisements.", 500);
  }
};

// ─── GET ONE ──────────────────────────────────────────────────────────────────

exports.getAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;
    if (!advertisementId || advertisementId === "undefined") return R.error(res, "Invalid advertisement ID.", 400);

    const advertisement = await Advertisement.findOne({
      where: { advertisement_id: advertisementId, ...notDeleted },
      include: [
        { model: mdl_Assets, as: "image", attributes: AD_IMAGE_ATTRIBUTES, required: false },
        { model: mdl_Users, as: "creator", attributes: ["user_id", "personal_info"], foreignKey: "createdBy" },
        { model: mdl_Users, as: "updater", attributes: ["user_id", "personal_info"], foreignKey: "updatedBy" },
      ],
    });

    if (!advertisement) return R.error(res, "Advertisement not found.", 404);

    const json = advertisement.toJSON();
    json.status = deriveStatus(json);

    if (json.image) await attachImageStreamToken(json.image, req);

    if (json.creator) {
      json.creator = {
        user_id:   json.creator.user_id,
        full_name: json.creator.personal_info?.name?.full_name ?? null,
      };
    }
    if (json.updater) {
      json.updater = {
        user_id:   json.updater.user_id,
        full_name: json.updater.personal_info?.name?.full_name ?? null,
      };
    }

    return R.success(res, "Advertisement retrieved.", { data: json });
  } catch (err) {
    console.error("[ADVERTISEMENT][GET ONE]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── CREATE ───────────────────────────────────────────────────────────────────

exports.createAdvertisement = async (req, res) => {
  try {
    const { placement, createdBy } = req.body;

    if (!placement) return R.error(res, "placement is required.", 400);
    const entry = PLACEMENT_MAP[placement];
    if (!entry) return R.error(res, `Invalid placement. Must be one of: ${PLACEMENT_KEYS.join(", ")}`, 400);
    if (!createdBy) return R.error(res, "createdBy is required.", 400);

    const t = await sequelize.transaction();
    try {
      const advertisement = await Advertisement.build({ placement, type: entry.format, createdBy });
      await applyAdvertisementFields(advertisement, req.body);

      // No manual "order" input in the UI anymore — new ads always append to
      // the end of their placement's priority list rather than colliding at 0.
      if (req.body.order === undefined) {
        advertisement.order = await Advertisement.count({ where: { placement, ...notDeleted }, transaction: t });
      }

      await advertisement.save({ transaction: t });
      await t.commit();

      logActivity(req.user?.user_id, 'create_advertisement', { entityType: 'advertisement', entityId: advertisement.advertisement_id, details: { placement: advertisement.placement, type: advertisement.type } });
      return R.success(res, "Advertisement created.", { data: advertisement }, 201);
    } catch (dbErr) {
      try { await t.rollback(); } catch { /* connection gone */ }
      throw dbErr;
    }
  } catch (err) {
    console.error("[ADVERTISEMENT][CREATE]", err);
    if (err.status) return R.error(res, err.message, err.status);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── UPDATE ───────────────────────────────────────────────────────────────────

exports.updateAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;
    if (!advertisementId || advertisementId === "undefined") return R.error(res, "Invalid advertisement ID.", 400);

    const advertisement = await Advertisement.findOne({ where: { advertisement_id: advertisementId, ...notDeleted } });
    if (!advertisement) return R.error(res, "Advertisement not found.", 404);

    const t = await sequelize.transaction();
    try {
      await applyAdvertisementFields(advertisement, req.body);
      advertisement.updatedBy = req.body.updatedBy ?? null;
      await advertisement.save({ transaction: t });
      await t.commit();

      logActivity(req.user?.user_id, 'update_advertisement', { entityType: 'advertisement', entityId: Number(advertisementId) });
      return R.success(res, "Advertisement updated.", { data: advertisement });
    } catch (dbErr) {
      try { await t.rollback(); } catch { /* gone */ }
      throw dbErr;
    }
  } catch (err) {
    console.error("[ADVERTISEMENT][UPDATE]", err);
    if (err.status) return R.error(res, err.message, err.status);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── REORDER ──────────────────────────────────────────────────────────────────
// `order` is scoped per placement (mirrors controllers/client/advertisements.controller.js's
// getActiveAdvertisement[List], which picks the lowest `order` within a placement to show
// first) — Move Up/Down swaps position among siblings sharing the same placement, then
// re-sequences the whole group to 0..n-1. Re-sequencing (not just swapping the two `order`
// values) is what makes this self-healing against legacy ties, since every ad defaulted to
// order: 0 before this feature existed — a plain swap between two tied rows would no-op.
exports.reorderAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;
    const { direction } = req.body;
    if (!["up", "down"].includes(direction)) return R.error(res, "direction must be 'up' or 'down'.", 400);

    const advertisement = await Advertisement.findOne({ where: { advertisement_id: advertisementId, ...notDeleted } });
    if (!advertisement) return R.error(res, "Advertisement not found.", 404);

    const group = await Advertisement.findAll({
      where: { placement: advertisement.placement, ...notDeleted },
      order: [["order", "ASC"], ["createdAt", "DESC"]],
    });

    const index = group.findIndex((a) => a.advertisement_id === advertisement.advertisement_id);
    const swapWith = direction === "up" ? index - 1 : index + 1;
    if (swapWith < 0 || swapWith >= group.length) {
      return R.error(res, `This ad is already at the ${direction === "up" ? "top" : "bottom"} of its placement.`, 400);
    }

    [group[index], group[swapWith]] = [group[swapWith], group[index]];

    const t = await sequelize.transaction();
    try {
      await Promise.all(group.map((a, i) => a.update({ order: i }, { transaction: t })));
      await t.commit();
    } catch (dbErr) {
      try { await t.rollback(); } catch { /* connection gone */ }
      throw dbErr;
    }

    logActivity(req.user?.user_id, 'reorder_advertisement', {
      entityType: 'advertisement', entityId: Number(advertisementId),
      details: { placement: advertisement.placement, direction },
    });
    return R.success(res, "Order updated.", {
      data: { updates: group.map((a) => ({ advertisement_id: a.advertisement_id, order: a.order })) },
    });
  } catch (err) {
    console.error("[ADVERTISEMENT][REORDER]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── ARCHIVE (single) ─────────────────────────────────────────────────────────

exports.archiveAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;
    if (!advertisementId || advertisementId === "undefined") return R.error(res, "Invalid advertisement ID.", 400);

    const advertisement = await Advertisement.findOne({ where: { advertisement_id: advertisementId, ...notDeleted } });
    if (!advertisement) return R.error(res, "Advertisement not found.", 404);

    // Freeze the derived status (e.g. "expired") onto the row before it goes
    // paranoid — the archived list trusts this stored value as-is and never
    // re-derives it, so "Remove Expired" would otherwise miss ads that had
    // already lapsed at the moment an admin manually archived them.
    await advertisement.update({ deletedBy: req.body.deletedBy ?? null, status: deriveStatus(advertisement) });
    await advertisement.destroy();
    logActivity(req.user?.user_id, 'archive_advertisement', { entityType: 'advertisement', entityId: Number(advertisementId) });
    return R.success(res, "Advertisement archived.");
  } catch (err) {
    console.error("[ADVERTISEMENT][ARCHIVE]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── ARCHIVE (bulk) ───────────────────────────────────────────────────────────

exports.archiveAdvertisements = async (req, res) => {
  try {
    const { ids, deletedBy } = req.body;
    if (!Array.isArray(ids) || !ids.length) return R.error(res, "ids must be a non-empty array.", 400);

    const advertisements = await Advertisement.findAll({ where: { advertisement_id: { [Op.in]: ids }, ...notDeleted } });
    if (!advertisements.length) return R.error(res, "No advertisements found.", 404);

    const activeIds = advertisements.map((a) => a.advertisement_id);

    // Same status-freeze as the single-archive path — resync each row's
    // status right before it goes paranoid so "Remove Expired" can trust it.
    await Promise.all(advertisements.map((a) =>
      a.update({ deletedBy: deletedBy ?? null, status: deriveStatus(a) })
    ));
    await Advertisement.destroy({ where: { advertisement_id: { [Op.in]: activeIds } } });

    logActivity(req.user?.user_id, 'bulk_archive_advertisements', { entityType: 'advertisement', details: { ids: activeIds, count: activeIds.length } });
    return R.success(res, `${activeIds.length} advertisement(s) archived.`, {
      archived_ids: activeIds,
      skipped_ids:  ids.filter((id) => !activeIds.includes(id)),
    });
  } catch (err) {
    console.error("[ADVERTISEMENT][BULK ARCHIVE]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── RESTORE (single) ─────────────────────────────────────────────────────────

exports.restoreAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;

    const advertisement = await Advertisement.findOne({ where: { advertisement_id: advertisementId }, paranoid: false });
    if (!advertisement) return R.error(res, "Advertisement not found.", 404);
    if (!advertisement.deletedAt) return R.error(res, "Advertisement is not archived.", 400);

    await advertisement.restore();
    await advertisement.update({ deletedBy: null });
    logActivity(req.user?.user_id, 'restore_advertisement', { entityType: 'advertisement', entityId: Number(advertisementId) });
    return R.success(res, "Advertisement restored.", { data: advertisement });
  } catch (err) {
    console.error("[ADVERTISEMENT][RESTORE]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── RESTORE (bulk) ───────────────────────────────────────────────────────────

exports.restoreAdvertisements = async (req, res) => {
  try {
    const { ids } = req.body;
    if (!Array.isArray(ids) || !ids.length) return R.error(res, "ids must be a non-empty array.", 400);

    const advertisements = await Advertisement.findAll({ where: { advertisement_id: { [Op.in]: ids } }, paranoid: false });
    if (!advertisements.length) return R.error(res, "No advertisements found.", 404);

    const archived = advertisements.filter((a) => a.deletedAt);
    if (!archived.length) return R.error(res, "All selected advertisements are already active.", 400);

    const archivedIds = archived.map((a) => a.advertisement_id);

    await Advertisement.restore({ where: { advertisement_id: { [Op.in]: archivedIds } } });
    await Advertisement.update({ deletedBy: null }, { where: { advertisement_id: { [Op.in]: archivedIds } }, paranoid: false });

    logActivity(req.user?.user_id, 'bulk_restore_advertisements', { entityType: 'advertisement', details: { ids: archivedIds, count: archivedIds.length } });
    return R.success(res, `${archivedIds.length} advertisement(s) restored.`, {
      restored_ids: archivedIds,
      skipped_ids:  ids.filter((id) => !archivedIds.includes(id)),
    });
  } catch (err) {
    console.error("[ADVERTISEMENT][BULK RESTORE]", err);
    return R.error(res, "Internal server error.", 500);
  }
};

// ─── ARCHIVED LIST ────────────────────────────────────────────────────────────

exports.getArchivedAdvertisements = async (req, res) => {
  try {
    const result = await paginate(Advertisement, req, {
      excludeAttributes: adminExclude,
      jsonbSchemas,
      computedAttributes,
      context: "archived",
      auditOptions: { mdl_Users, parentAlias: 'Advertisement' },
      findOptions: { paranoid: false, where: { deletedAt: { [Op.ne]: null } } },
    });
    return R.success(res, "Archived advertisements retrieved.", result);
  } catch (err) {
    console.error("[ADVERTISEMENT][GET ARCHIVED]", err);
    return R.error(res, "Could not retrieve archived advertisements.", 500);
  }
};

exports.getAdvertisementFieldValues = getFieldValues(Advertisement, "ADVERTISEMENT");

// ─── PERMANENT DELETE (single) ────────────────────────────────────────────────

exports.permanentlyDeleteAdvertisement = async (req, res) => {
  try {
    const { advertisementId } = req.params;

    const advertisement = await Advertisement.findOne({ where: { advertisement_id: advertisementId }, paranoid: false });
    if (!advertisement) return R.error(res, "Advertisement not found.", 404);
    if (!advertisement.deletedAt) return R.error(res, "Advertisement must be archived before it can be permanently deleted.", 400);

    await advertisement.destroy({ force: true });
    logActivity(req.user?.user_id, 'permanently_delete_advertisement', { entityType: 'advertisement', entityId: Number(advertisementId) });
    return R.success(res, "Advertisement permanently deleted.");
  } catch (err) {
    console.error("[ADVERTISEMENT][PERMANENT DELETE]", err);
    return R.error(res, "Could not permanently delete advertisement.", 500);
  }
};

// ─── PERMANENT DELETE (bulk) ───────────────────────────────────────────────────

exports.permanentlyDeleteAdvertisements = async (req, res) => {
  try {
    const { ids } = req.body;
    if (!Array.isArray(ids) || !ids.length) return R.error(res, "ids must be a non-empty array.", 400);

    const advertisements = await Advertisement.findAll({ where: { advertisement_id: { [Op.in]: ids } }, paranoid: false });
    if (!advertisements.length) return R.error(res, "No advertisements found.", 404);

    const archived = advertisements.filter((a) => a.deletedAt);
    if (!archived.length) return R.error(res, "All selected advertisements must be archived before they can be permanently deleted.", 400);

    const archivedIds = archived.map((a) => a.advertisement_id);

    await Advertisement.destroy({ where: { advertisement_id: { [Op.in]: archivedIds } }, force: true });

    logActivity(req.user?.user_id, 'bulk_permanently_delete_advertisements', { entityType: 'advertisement', details: { ids: archivedIds, count: archivedIds.length } });
    return R.success(res, `${archivedIds.length} advertisement(s) permanently deleted.`, {
      deleted_ids: archivedIds,
      skipped_ids: ids.filter((id) => !archivedIds.includes(id)),
    });
  } catch (err) {
    console.error("[ADVERTISEMENT][BULK PERMANENT DELETE]", err);
    return R.error(res, "Could not permanently delete advertisements.", 500);
  }
};