"use strict";

const express = require("express"),
  fs = require("fs"),
  url = require("url"),
  config = require("config"),
  moment = require("moment");

let photoDB;

require("../db").then(function(db) {
  photoDB = db;
});

const router = express.Router();

/* Each photos has:

* locations
* people
* date
* tags
* photo info

*/

router.get("/", function(req, res/*, next*/) {
  let limit = parseInt(req.query.limit) || 50,
    order = (parseInt(req.query.dir) == -1) ? "DESC" : "", id, cursor, index;

  if (req.query.next) {
    let parts = req.query.next.split("_");
    cursor = parts[0];
    id = parseInt(parts[1]);
  } else {
    cursor = "";
    id = -1;
  }

  if (id == -1) {
    index = "";
  } else {
    if (order == "DESC") {
      if (id != -1) {
        index = " AND ((taken=DATE(:cursor) AND id<"+id+ ") OR taken<DATE(:cursor))";
      } else {
        index = " AND (taken<=DATE(:cursor))";
      }
    } else {
      if (id != -1) {
        index = " AND ((taken=DATE(:cursor) AND id>"+id+ ") OR taken>DATE(:cursor))";
      } else {
        index = " AND (taken>=DATE(:cursor))";
      }
    }
  }

  let query = "SELECT * FROM photos WHERE path LIKE :path " + index + " ORDER BY taken " + order + ",id " + order + " LIMIT " + (limit * 2 + 1);
  return photoDB.sequelize.query(query, {
    replacements: {
      cursor: cursor,
      path: req.url.replace(/\?.*$/, "") + "%"
    },
    type: photoDB.Sequelize.QueryTypes.SELECT
  }).then(function(photos) {
    photos.forEach(function(photo) {
      for (var key in photo) {
        if (photo[key] instanceof Date) {
          photo[key].setHours(0, 0, 0, 0);
          photo[key] = moment(photo[key]);
        }
      }
    });

    if (order == "DESC") {
      if (cursor) {
         photos = photos.filter(function(photo) {
          if (!cursor.isSame(photo.taken, "day")) {
            return true;
          }
          return photo.id < id;
        });
      }
      photos.reverse();
    } else {
      if (cursor) {
        cursor = moment(cursor);
        photos = photos.filter(function(photo) {
          if (!cursor.isSame(photo.taken, "day")) {
            return true;
          }
          return photo.id > id;
        });
      }
    }

    let more = photos.length > limit; /* We queried one extra item to see if there are more than LIMIT available */

    if (more) {
      photos.slice(limit, photos.length);
    }
    photos.forEach(function(photo) {
      photo.path = encodeURI(photo.path);
      photo.filename = encodeURI(photo.filename);
    });

    let results = {
      items: photos
    };
    if (more) {
      results.more = true;
    }
    return res.status(200).json(results);
  }).catch(function(error) {
    console.error("Query failed: " + query);
    return Promise.reject(error);
  });
});

module.exports = router;