// @flow
import Router from "koa-router";
import Sequelize from "sequelize";
import auth from "../middlewares/authentication";
import pagination from "./middlewares/pagination";
import documentMover from "../commands/documentMover";
import {
  presentDocument,
  presentCollection,
  presentPolicies,
} from "../presenters";
import {
  Collection,
  Document,
  Event,
  Share,
  Star,
  View,
  Revision,
  Backlink,
  User,
} from "../models";
import { InvalidRequestError } from "../errors";
import policy from "../policies";
import { sequelize } from "../sequelize";

const Op = Sequelize.Op;
const { authorize, cannot } = policy;
const router = new Router();

router.post("documents.list", auth(), pagination(), async ctx => {
  const { sort = "updatedAt", backlinkDocumentId, parentDocumentId } = ctx.body;

  // collection and user are here for backwards compatibility
  const collectionId = ctx.body.collectionId || ctx.body.collection;
  const createdById = ctx.body.userId || ctx.body.user;
  let direction = ctx.body.direction;
  if (direction !== "ASC") direction = "DESC";

  // always filter by the current team
  const user = ctx.state.user;
  let where = { teamId: user.teamId };

  // if a specific user is passed then add to filters. If the user doesn't
  // exist in the team then nothing will be returned, so no need to check auth
  if (createdById) {
    ctx.assertUuid(createdById, "user must be a UUID");
    where = { ...where, createdById };
  }

  // if a specific collection is passed then we need to check auth to view it
  if (collectionId) {
    ctx.assertUuid(collectionId, "collection must be a UUID");

    where = { ...where, collectionId };
    const collection = await Collection.scope({
      method: ["withMembership", user.id],
    }).findByPk(collectionId);
    authorize(user, "read", collection);

    // otherwise, filter by all collections the user has access to
  } else {
    const collectionIds = await user.collectionIds();
    where = { ...where, collectionId: collectionIds };
  }

  if (parentDocumentId) {
    ctx.assertUuid(parentDocumentId, "parentDocumentId must be a UUID");
    where = { ...where, parentDocumentId };
  }

  if (backlinkDocumentId) {
    ctx.assertUuid(backlinkDocumentId, "backlinkDocumentId must be a UUID");

    const backlinks = await Backlink.findAll({
      attributes: ["reverseDocumentId"],
      where: {
        documentId: backlinkDocumentId,
      },
    });

    where = {
      ...where,
      id: backlinks.map(backlink => backlink.reverseDocumentId),
    };
  }

  // add the users starred state to the response by default
  const starredScope = { method: ["withStarred", user.id] };
  const collectionScope = { method: ["withCollection", user.id] };
  const documents = await Document.scope(
    "defaultScope",
    starredScope,
    collectionScope
  ).findAll({
    where,
    order: [[sort, direction]],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.pinned", auth(), pagination(), async ctx => {
  const { collectionId, sort = "updatedAt" } = ctx.body;
  let direction = ctx.body.direction;
  if (direction !== "ASC") direction = "DESC";
  ctx.assertUuid(collectionId, "collectionId is required");

  const user = ctx.state.user;
  const collection = await Collection.scope({
    method: ["withMembership", user.id],
  }).findByPk(collectionId);

  authorize(user, "read", collection);

  const starredScope = { method: ["withStarred", user.id] };
  const collectionScope = { method: ["withCollection", user.id] };
  const documents = await Document.scope(
    "defaultScope",
    starredScope,
    collectionScope
  ).findAll({
    where: {
      teamId: user.teamId,
      collectionId,
      pinnedById: {
        [Op.ne]: null,
      },
    },
    order: [[sort, direction]],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.archived", auth(), pagination(), async ctx => {
  const { sort = "updatedAt" } = ctx.body;
  let direction = ctx.body.direction;
  if (direction !== "ASC") direction = "DESC";

  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();

  const collectionScope = { method: ["withCollection", user.id] };
  const documents = await Document.scope(
    "defaultScope",
    collectionScope
  ).findAll({
    where: {
      teamId: user.teamId,
      collectionId: collectionIds,
      archivedAt: {
        [Op.ne]: null,
      },
    },
    order: [[sort, direction]],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.deleted", auth(), pagination(), async ctx => {
  const { sort = "deletedAt" } = ctx.body;
  let direction = ctx.body.direction;
  if (direction !== "ASC") direction = "DESC";

  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();

  const collectionScope = { method: ["withCollection", user.id] };
  const documents = await Document.scope(collectionScope).findAll({
    where: {
      teamId: user.teamId,
      collectionId: collectionIds,
      deletedAt: {
        [Op.ne]: null,
      },
    },
    include: [
      { model: User, as: "createdBy", paranoid: false },
      { model: User, as: "updatedBy", paranoid: false },
    ],
    paranoid: false,
    order: [[sort, direction]],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.viewed", auth(), pagination(), async ctx => {
  let { sort = "updatedAt", direction } = ctx.body;
  if (direction !== "ASC") direction = "DESC";

  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();

  const views = await View.findAll({
    where: { userId: user.id },
    order: [[sort, direction]],
    include: [
      {
        model: Document,
        required: true,
        where: {
          collectionId: collectionIds,
        },
        include: [
          {
            model: Star,
            as: "starred",
            where: { userId: user.id },
            required: false,
          },
        ],
      },
    ],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const documents = views.map(view => view.document);
  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.starred", auth(), pagination(), async ctx => {
  let { sort = "updatedAt", direction } = ctx.body;
  if (direction !== "ASC") direction = "DESC";

  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();

  const stars = await Star.findAll({
    where: {
      userId: user.id,
    },
    order: [[sort, direction]],
    include: [
      {
        model: Document,
        where: {
          collectionId: collectionIds,
        },
        include: [
          {
            model: Collection,
            as: "collection",
          },
          {
            model: Star,
            as: "starred",
            where: {
              userId: user.id,
            },
          },
        ],
      },
    ],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const documents = stars.map(star => star.document);
  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.drafts", auth(), pagination(), async ctx => {
  let { sort = "updatedAt", direction } = ctx.body;
  if (direction !== "ASC") direction = "DESC";

  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();

  const collectionScope = { method: ["withCollection", user.id] };
  const documents = await Document.scope(
    "defaultScope",
    collectionScope
  ).findAll({
    where: {
      userId: user.id,
      collectionId: collectionIds,
      publishedAt: { [Op.eq]: null },
    },
    order: [[sort, direction]],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  const data = await Promise.all(
    documents.map(document => presentDocument(document))
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

async function loadDocument({ id, shareId, user }) {
  let document;

  if (shareId) {
    const share = await Share.findOne({
      where: {
        revokedAt: { [Op.eq]: null },
        id: shareId,
      },
      include: [
        {
          // unscoping here allows us to return unpublished documents
          model: Document.unscoped(),
          include: [
            { model: User, as: "createdBy", paranoid: false },
            { model: User, as: "updatedBy", paranoid: false },
          ],
          required: true,
          as: "document",
        },
      ],
    });
    if (!share || share.document.archivedAt) {
      throw new InvalidRequestError("Document could not be found for shareId");
    }

    document = share.document;

    if (!share.published) {
      authorize(user, "read", document);
    }
  } else {
    document = await Document.findByPk(
      id,
      user ? { userId: user.id } : undefined
    );
    authorize(user, "read", document);
  }

  return document;
}

router.post("documents.info", auth({ required: false }), async ctx => {
  const { id, shareId } = ctx.body;
  ctx.assertPresent(id || shareId, "id or shareId is required");

  const user = ctx.state.user;
  const document = await loadDocument({ id, shareId, user });
  const isPublic = cannot(user, "read", document);

  ctx.body = {
    data: await presentDocument(document, { isPublic }),
    policies: isPublic ? undefined : presentPolicies(user, [document]),
  };
});

router.post("documents.export", auth({ required: false }), async ctx => {
  const { id, shareId } = ctx.body;
  ctx.assertPresent(id || shareId, "id or shareId is required");

  const user = ctx.state.user;
  const document = await loadDocument({ id, shareId, user });

  ctx.body = {
    data: document.toMarkdown(),
  };
});

router.post("documents.restore", auth(), async ctx => {
  const { id, revisionId } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, {
    userId: user.id,
    paranoid: false,
  });

  if (document.deletedAt) {
    authorize(user, "restore", document);

    // restore a previously deleted document
    await document.unarchive(user.id);

    await Event.create({
      name: "documents.restore",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: { title: document.title },
      ip: ctx.request.ip,
    });
  } else if (document.archivedAt) {
    authorize(user, "unarchive", document);

    // restore a previously archived document
    await document.unarchive(user.id);

    await Event.create({
      name: "documents.unarchive",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: { title: document.title },
      ip: ctx.request.ip,
    });
  } else if (revisionId) {
    // restore a document to a specific revision
    authorize(user, "update", document);

    const revision = await Revision.findByPk(revisionId);
    authorize(document, "restore", revision);

    document.text = revision.text;
    document.title = revision.title;
    await document.save();

    await Event.create({
      name: "documents.restore",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: { title: document.title },
      ip: ctx.request.ip,
    });
  } else {
    ctx.assertPresent(revisionId, "revisionId is required");
  }

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.search", auth(), pagination(), async ctx => {
  const {
    query,
    includeArchived,
    includeDrafts,
    collectionId,
    userId,
    dateFilter,
  } = ctx.body;
  const { offset, limit } = ctx.state.pagination;
  const user = ctx.state.user;
  ctx.assertPresent(query, "query is required");

  if (collectionId) {
    ctx.assertUuid(collectionId, "collectionId must be a UUID");

    const collection = await Collection.scope({
      method: ["withMembership", user.id],
    }).findByPk(collectionId);
    authorize(user, "read", collection);
  }

  let collaboratorIds = undefined;
  if (userId) {
    ctx.assertUuid(userId, "userId must be a UUID");
    collaboratorIds = [userId];
  }

  if (dateFilter) {
    ctx.assertIn(
      dateFilter,
      ["day", "week", "month", "year"],
      "dateFilter must be one of day,week,month,year"
    );
  }

  const results = await Document.searchForUser(user, query, {
    includeArchived: includeArchived === "true",
    includeDrafts: includeDrafts === "true",
    collaboratorIds,
    collectionId,
    dateFilter,
    offset,
    limit,
  });

  const documents = results.map(result => result.document);
  const data = await Promise.all(
    results.map(async result => {
      const document = await presentDocument(result.document);
      return { ...result, document };
    })
  );

  const policies = presentPolicies(user, documents);

  ctx.body = {
    pagination: ctx.state.pagination,
    data,
    policies,
  };
});

router.post("documents.pin", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "pin", document);

  document.pinnedById = user.id;
  await document.save();

  await Event.create({
    name: "documents.pin",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.unpin", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "unpin", document);

  document.pinnedById = null;
  await document.save();

  await Event.create({
    name: "documents.unpin",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.star", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "read", document);

  await Star.findOrCreate({
    where: { documentId: document.id, userId: user.id },
  });

  await Event.create({
    name: "documents.star",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    success: true,
  };
});

router.post("documents.unstar", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "read", document);

  await Star.destroy({
    where: { documentId: document.id, userId: user.id },
  });

  await Event.create({
    name: "documents.unstar",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    success: true,
  };
});

router.post("documents.create", auth(), async ctx => {
  const {
    title = "",
    text = "",
    publish,
    collectionId,
    parentDocumentId,
    index,
  } = ctx.body;
  const editorVersion = ctx.headers["x-editor-version"];

  ctx.assertUuid(collectionId, "collectionId must be an uuid");
  if (parentDocumentId) {
    ctx.assertUuid(parentDocumentId, "parentDocumentId must be an uuid");
  }

  if (index) ctx.assertPositiveInteger(index, "index must be an integer (>=0)");

  const user = ctx.state.user;
  authorize(user, "create", Document);

  const collection = await Collection.scope({
    method: ["withMembership", user.id],
  }).findOne({
    where: {
      id: collectionId,
      teamId: user.teamId,
    },
  });
  authorize(user, "publish", collection);

  let parentDocument;
  if (parentDocumentId && collection.type === "atlas") {
    parentDocument = await Document.findOne({
      where: {
        id: parentDocumentId,
        collectionId: collection.id,
      },
    });
    authorize(user, "read", parentDocument, { collection });
  }

  let document = await Document.create({
    parentDocumentId,
    editorVersion,
    collectionId: collection.id,
    teamId: user.teamId,
    userId: user.id,
    lastModifiedById: user.id,
    createdById: user.id,
    title,
    text,
  });

  await Event.create({
    name: "documents.create",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  if (publish) {
    await document.publish();

    await Event.create({
      name: "documents.publish",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: { title: document.title },
      ip: ctx.request.ip,
    });
  }

  // reload to get all of the data needed to present (user, collection etc)
  // we need to specify publishedAt to bypass default scope that only returns
  // published documents
  document = await Document.findOne({
    where: { id: document.id, publishedAt: document.publishedAt },
  });
  document.collection = collection;

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.update", auth(), async ctx => {
  const {
    id,
    title,
    text,
    publish,
    autosave,
    done,
    lastRevision,
    append,
  } = ctx.body;
  const editorVersion = ctx.headers["x-editor-version"];

  ctx.assertPresent(id, "id is required");
  ctx.assertPresent(title || text, "title or text is required");
  if (append) ctx.assertPresent(text, "Text is required while appending");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "update", document);

  if (lastRevision && lastRevision !== document.revisionCount) {
    throw new InvalidRequestError("Document has changed since last revision");
  }

  // Update document
  if (title) document.title = title;
  if (editorVersion) document.editorVersion = editorVersion;

  if (append) {
    document.text += text;
  } else if (text !== undefined) {
    document.text = text;
  }
  document.lastModifiedById = user.id;
  const { collection } = document;

  let transaction;
  try {
    transaction = await sequelize.transaction();

    if (publish) {
      await document.publish({ transaction });
    } else {
      await document.save({ autosave, transaction });
    }
    await transaction.commit();
  } catch (err) {
    if (transaction) {
      await transaction.rollback();
    }
    throw err;
  }

  if (publish) {
    await Event.create({
      name: "documents.publish",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: { title: document.title },
      ip: ctx.request.ip,
    });
  } else {
    await Event.create({
      name: "documents.update",
      documentId: document.id,
      collectionId: document.collectionId,
      teamId: document.teamId,
      actorId: user.id,
      data: {
        autosave,
        done,
        title: document.title,
      },
      ip: ctx.request.ip,
    });
  }

  document.updatedBy = user;
  document.collection = collection;

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.move", auth(), async ctx => {
  const { id, collectionId, parentDocumentId, index } = ctx.body;
  ctx.assertUuid(id, "id must be a uuid");
  ctx.assertUuid(collectionId, "collectionId must be a uuid");

  if (parentDocumentId) {
    ctx.assertUuid(parentDocumentId, "parentDocumentId must be a uuid");
  }
  if (index) {
    ctx.assertPositiveInteger(index, "index must be a positive integer");
  }
  if (parentDocumentId === id) {
    throw new InvalidRequestError(
      "Infinite loop detected, cannot nest a document inside itself"
    );
  }

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "move", document);

  const { collection } = document;
  if (collection.type !== "atlas" && parentDocumentId) {
    throw new InvalidRequestError(
      "Document cannot be nested in this collection type"
    );
  }

  if (parentDocumentId) {
    const parent = await Document.findByPk(parentDocumentId, {
      userId: user.id,
    });
    authorize(user, "update", parent);
  }

  const { documents, collections } = await documentMover({
    user,
    document,
    collectionId,
    parentDocumentId,
    index,
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: {
      documents: await Promise.all(
        documents.map(document => presentDocument(document))
      ),
      collections: await Promise.all(
        collections.map(collection => presentCollection(collection))
      ),
    },
    policies: presentPolicies(user, documents),
  };
});

router.post("documents.archive", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "archive", document);

  await document.archive(user.id);

  await Event.create({
    name: "documents.archive",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: await presentDocument(document),
    policies: presentPolicies(user, [document]),
  };
});

router.post("documents.delete", auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertPresent(id, "id is required");

  const user = ctx.state.user;
  const document = await Document.findByPk(id, { userId: user.id });
  authorize(user, "delete", document);

  await document.delete();

  await Event.create({
    name: "documents.delete",
    documentId: document.id,
    collectionId: document.collectionId,
    teamId: document.teamId,
    actorId: user.id,
    data: { title: document.title },
    ip: ctx.request.ip,
  });

  ctx.body = {
    success: true,
  };
});

export default router;