// @flow
import fs from 'fs';
import Router from 'koa-router';
import { Op } from '../sequelize';
import auth from '../middlewares/authentication';
import pagination from './middlewares/pagination';
import {
  presentCollection,
  presentUser,
  presentPolicies,
  presentMembership,
  presentGroup,
  presentCollectionGroupMembership,
} from '../presenters';
import {
  Collection,
  CollectionUser,
  CollectionGroup,
  Team,
  Event,
  User,
  Group,
} from '../models';
import { ValidationError } from '../errors';
import { exportCollections } from '../logistics';
import { archiveCollection, archiveCollections } from '../utils/zip';
import policy from '../policies';

const { authorize } = policy;
const router = new Router();

router.post('collections.create', auth(), async ctx => {
  const { name, color, description, type } = ctx.body;
  const isPrivate = ctx.body.private;
  ctx.assertPresent(name, 'name is required');

  if (color) {
    ctx.assertHexColor(color, 'Invalid hex value (please use format #FFFFFF)');
  }

  const user = ctx.state.user;
  authorize(user, 'create', Collection);

  let collection = await Collection.create({
    name,
    description,
    color,
    type: type || 'atlas',
    teamId: user.teamId,
    creatorId: user.id,
    private: isPrivate,
  });

  await Event.create({
    name: 'collections.create',
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: user.id,
    data: { name },
    ip: ctx.request.ip,
  });

  // we must reload the collection to get memberships for policy presenter
  if (isPrivate) {
    collection = await Collection.scope({
      method: ['withMembership', user.id],
    }).findByPk(collection.id);
  }

  ctx.body = {
    data: presentCollection(collection),
    policies: presentPolicies(user, [collection]),
  };
});

router.post('collections.info', auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertUuid(id, 'id is required');

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

  ctx.body = {
    data: presentCollection(collection),
    policies: presentPolicies(user, [collection]),
  };
});

router.post('collections.add_group', auth(), async ctx => {
  const { id, groupId, permission = 'read_write' } = ctx.body;
  ctx.assertUuid(id, 'id is required');
  ctx.assertUuid(groupId, 'groupId is required');

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

  const group = await Group.findByPk(groupId);
  authorize(ctx.state.user, 'read', group);

  let membership = await CollectionGroup.findOne({
    where: {
      collectionId: id,
      groupId,
    },
  });

  if (!membership) {
    membership = await CollectionGroup.create({
      collectionId: id,
      groupId,
      permission,
      createdById: ctx.state.user.id,
    });
  } else if (permission) {
    membership.permission = permission;
    await membership.save();
  }

  await Event.create({
    name: 'collections.add_group',
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: ctx.state.user.id,
    data: { name: group.name, groupId },
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: {
      collectionGroupMemberships: [
        presentCollectionGroupMembership(membership),
      ],
    },
  };
});

router.post('collections.remove_group', auth(), async ctx => {
  const { id, groupId } = ctx.body;
  ctx.assertUuid(id, 'id is required');
  ctx.assertUuid(groupId, 'groupId is required');

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

  const group = await Group.findByPk(groupId);
  authorize(ctx.state.user, 'read', group);

  await collection.removeGroup(group);

  await Event.create({
    name: 'collections.remove_group',
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: ctx.state.user.id,
    data: { name: group.name, groupId },
    ip: ctx.request.ip,
  });

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

router.post(
  'collections.group_memberships',
  auth(),
  pagination(),
  async ctx => {
    const { id, query, permission } = ctx.body;
    ctx.assertUuid(id, 'id is required');

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

    authorize(user, 'read', collection);

    let where = {
      collectionId: id,
    };

    let groupWhere;

    if (query) {
      groupWhere = {
        name: {
          [Op.iLike]: `%${query}%`,
        },
      };
    }

    if (permission) {
      where = {
        ...where,
        permission,
      };
    }

    const memberships = await CollectionGroup.findAll({
      where,
      order: [['createdAt', 'DESC']],
      offset: ctx.state.pagination.offset,
      limit: ctx.state.pagination.limit,
      include: [
        {
          model: Group,
          as: 'group',
          where: groupWhere,
          required: true,
        },
      ],
    });

    ctx.body = {
      pagination: ctx.state.pagination,
      data: {
        collectionGroupMemberships: memberships.map(
          presentCollectionGroupMembership
        ),
        groups: memberships.map(membership => presentGroup(membership.group)),
      },
    };
  }
);

router.post('collections.add_user', auth(), async ctx => {
  const { id, userId, permission = 'read_write' } = ctx.body;
  ctx.assertUuid(id, 'id is required');
  ctx.assertUuid(userId, 'userId is required');

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

  const user = await User.findByPk(userId);
  authorize(ctx.state.user, 'read', user);

  let membership = await CollectionUser.findOne({
    where: {
      collectionId: id,
      userId,
    },
  });

  if (!membership) {
    membership = await CollectionUser.create({
      collectionId: id,
      userId,
      permission,
      createdById: ctx.state.user.id,
    });
  } else if (permission) {
    membership.permission = permission;
    await membership.save();
  }

  await Event.create({
    name: 'collections.add_user',
    userId,
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: ctx.state.user.id,
    data: { name: user.name },
    ip: ctx.request.ip,
  });

  ctx.body = {
    data: {
      users: [presentUser(user)],
      memberships: [presentMembership(membership)],
    },
  };
});

router.post('collections.remove_user', auth(), async ctx => {
  const { id, userId } = ctx.body;
  ctx.assertUuid(id, 'id is required');
  ctx.assertUuid(userId, 'userId is required');

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

  const user = await User.findByPk(userId);
  authorize(ctx.state.user, 'read', user);

  await collection.removeUser(user);

  await Event.create({
    name: 'collections.remove_user',
    userId,
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: ctx.state.user.id,
    data: { name: user.name },
    ip: ctx.request.ip,
  });

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

// DEPRECATED: Use collection.memberships which has pagination, filtering and permissions
router.post('collections.users', auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertUuid(id, 'id is required');

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

  const users = await collection.getUsers();

  ctx.body = {
    data: users.map(presentUser),
  };
});

router.post('collections.memberships', auth(), pagination(), async ctx => {
  const { id, query, permission } = ctx.body;
  ctx.assertUuid(id, 'id is required');

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

  let where = {
    collectionId: id,
  };

  let userWhere;

  if (query) {
    userWhere = {
      name: {
        [Op.iLike]: `%${query}%`,
      },
    };
  }

  if (permission) {
    where = {
      ...where,
      permission,
    };
  }

  const memberships = await CollectionUser.findAll({
    where,
    order: [['createdAt', 'DESC']],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
    include: [
      {
        model: User,
        as: 'user',
        where: userWhere,
        required: true,
      },
    ],
  });

  ctx.body = {
    pagination: ctx.state.pagination,
    data: {
      memberships: memberships.map(presentMembership),
      users: memberships.map(membership => presentUser(membership.user)),
    },
  };
});

router.post('collections.export', auth(), async ctx => {
  const { id } = ctx.body;
  ctx.assertUuid(id, 'id is required');

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

  const filePath = await archiveCollection(collection);

  await Event.create({
    name: 'collections.export',
    collectionId: collection.id,
    teamId: user.teamId,
    actorId: user.id,
    data: { title: collection.title },
    ip: ctx.request.ip,
  });

  ctx.attachment(`${collection.name}.zip`);
  ctx.set('Content-Type', 'application/force-download');
  ctx.body = fs.createReadStream(filePath);
});

router.post('collections.exportAll', auth(), async ctx => {
  const { download = false } = ctx.body;

  const user = ctx.state.user;
  const team = await Team.findByPk(user.teamId);
  authorize(user, 'export', team);

  await Event.create({
    name: 'collections.export',
    teamId: user.teamId,
    actorId: user.id,
    ip: ctx.request.ip,
  });

  if (download) {
    const collections = await Collection.findAll({
      where: { teamId: team.id },
      order: [['name', 'ASC']],
    });
    const filePath = await archiveCollections(collections);

    ctx.attachment(`${team.name}.zip`);
    ctx.set('Content-Type', 'application/force-download');
    ctx.body = fs.createReadStream(filePath);
  } else {
    // async operation to create zip archive and email user
    exportCollections(user.teamId, user.email);

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

router.post('collections.update', auth(), async ctx => {
  const { id, name, description, color } = ctx.body;
  const isPrivate = ctx.body.private;
  ctx.assertPresent(name, 'name is required');

  if (color) {
    ctx.assertHexColor(color, 'Invalid hex value (please use format #FFFFFF)');
  }

  const user = ctx.state.user;

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

  authorize(user, 'update', collection);

  // we're making this collection private right now, ensure that the current
  // user has a read-write membership so that at least they can edit it
  if (isPrivate && !collection.private) {
    await CollectionUser.findOrCreate({
      where: {
        collectionId: collection.id,
        userId: user.id,
      },
      defaults: {
        permission: 'read_write',
        createdById: user.id,
      },
    });
  }

  const isPrivacyChanged = isPrivate !== collection.private;

  collection.name = name;
  collection.description = description;
  collection.color = color;
  collection.private = isPrivate;

  await collection.save();

  await Event.create({
    name: 'collections.update',
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: user.id,
    data: { name },
    ip: ctx.request.ip,
  });

  // must reload to update collection membership for correct policy calculation
  // if the privacy level has changed. Otherwise skip this query for speed.
  if (isPrivacyChanged) {
    await collection.reload();
  }

  ctx.body = {
    data: presentCollection(collection),
    policies: presentPolicies(user, [collection]),
  };
});

router.post('collections.list', auth(), pagination(), async ctx => {
  const user = ctx.state.user;
  const collectionIds = await user.collectionIds();
  let collections = await Collection.scope({
    method: ['withMembership', user.id],
  }).findAll({
    where: {
      teamId: user.teamId,
      id: collectionIds,
    },
    order: [['updatedAt', 'DESC']],
    offset: ctx.state.pagination.offset,
    limit: ctx.state.pagination.limit,
  });

  ctx.body = {
    pagination: ctx.state.pagination,
    data: collections.map(presentCollection),
    policies: presentPolicies(user, collections),
  };
});

router.post('collections.delete', auth(), async ctx => {
  const { id } = ctx.body;
  const user = ctx.state.user;
  ctx.assertUuid(id, 'id is required');

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

  authorize(user, 'delete', collection);

  const total = await Collection.count();
  if (total === 1) throw new ValidationError('Cannot delete last collection');

  await collection.destroy();

  await Event.create({
    name: 'collections.delete',
    collectionId: collection.id,
    teamId: collection.teamId,
    actorId: user.id,
    data: { name: collection.name },
    ip: ctx.request.ip,
  });

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

export default router;