const logger = require('winston');

const returnShortId = (claimsArray, longId) => {
  let claimIndex;
  let shortId = longId.substring(0, 1); // default short id is the first letter
  let shortIdLength = 0;
  // find the index of this claim id
  claimIndex = claimsArray.findIndex(element => {
    return element.claim_id === longId;
  });
  if (claimIndex < 0) {
    throw new Error('claim id not found in claims list');
  }
  // get an array of all claims with lower height
  let possibleMatches = claimsArray.slice(0, claimIndex);
  // remove certificates with the same prefixes until none are left.
  while (possibleMatches.length > 0) {
    shortIdLength += 1;
    shortId = longId.substring(0, shortIdLength);
    possibleMatches = possibleMatches.filter(element => {
      return (element.claim_id && (element.claim_id.substring(0, shortIdLength) === shortId));
    });
  }
  return shortId;
};

const isLongClaimId = (claimId) => {
  return (claimId && (claimId.length === 40));
}

const isShortClaimId = (claimId) => {
  return (claimId && (claimId.length < 40));
}

export default (db, table) => ({

  getShortClaimIdFromLongClaimId: async (claimId, claimName) => {
    logger.debug(`claim.getShortClaimIdFromLongClaimId for ${claimName}#${claimId}`);
    return await table.findAll({
      where: { name: claimName },
      order: [['height', 'ASC']],
    }).then(result => {
      if(result.length === 0) {
        throw new Error('No claim(s) found with that claim name');
      }

      return returnShortId(result, claimId);
    });
  },

  getAllChannelClaims: async (channelClaimId) => {
    logger.debug(`claim.getAllChannelClaims for ${channelClaimId}`);
    return await table.findAll({
      where: { publisher_id: channelClaimId },
      order: [['height', 'DESC']],
      raw  : true,  // returns an array of only data, not an array of instances
    })
    .then(channelClaimsArray => {
      if(channelClaimsArray.length === 0) {
        return null;
      }

      return channelClaimsArray;
    })
  },

  getClaimIdByLongChannelId: async (channelClaimId, claimName) => {
    logger.debug(`finding claim id for claim ${claimName} from channel ${channelClaimId}`);
    return await table.findAll({
      where: { name: claimName, publisher_id: channelClaimId },
      order: [['id', 'ASC']],
    })
    .then(result => {
      switch (result.length) {
        case 0:
          return null;
        case 1:
          return result[0].claim_id;
        default:
          // Does this actually happen??? (from converted code)
          logger.warn(`${result.length} records found for "${claimName}" in channel "${channelClaimId}"`);
          return result[0].claim_id;
      }
    });
  },

  validateLongClaimId: async (name, claimId) => {
    return await table.findOne({
      where: {
        name,
        claim_id: claimId,
      },
    }).then(result => {
      if (!result) {
        return false;
      }
      return claimId;
    });
  },

  getLongClaimIdFromShortClaimId: async (name, shortId) => {
    return await table.findAll({
      where: {
        name,
        claim_id: {
          [sequelize.Op.like]: `${shortId}%`,
        }},
      order: [['height', 'ASC']],
    })
    .then(result => {
      if(result.length === 0) {
        return null;
      }

      return result[0].claim_id;
    });
  },

  getTopFreeClaimIdByClaimName: async (name) => {
    return await table.findAll({
      // TODO: Limit 1
      where: { name },
      order: [['effective_amount', 'DESC'], ['height', 'ASC']],
    }).then(result => {
      if(result.length === 0) {
        return null;
      }
      return result[0].claim_id;
    })
  },

  getLongClaimId: async (claimName, claimId) => {
    // TODO: Add failure case
    logger.debug(`getLongClaimId(${claimName}, ${claimId})`);
    if (isLongClaimId(claimId)) {
      return table.queries.validateLongClaimId(claimName, claimId);
    } else if (isShortClaimId(claimId)) {
      return table.queries.getLongClaimIdFromShortClaimId(claimName, claimId);
    } else {
      return table.queries.getTopFreeClaimIdByClaimName(claimName);
    }
  },

  resolveClaim: async (name, claimId) => {
    logger.debug(`Claim.resolveClaim: ${name} ${claimId}`);
    return table.findAll({
      where: { name, claim_id: claimId },
    }).then(claimArray => {
      if(claimArray.length === 0) {
        return null;
      } else if(claimArray.length !== 1) {
        logger.warn(`more than one record matches ${name}#${claimId} in db.Claim`);
      }

      return claimArray[0];
    });
  },

  getOutpoint: async (name, claimId) => {
    logger.debug(`finding outpoint for ${name}#${claimId}`);

    return await table.findAll({
      where     : { name, claim_id: claimId },
      attributes: ['transaction_hash_id'],
    }).then(result => {
      if(result.length === 0) {
        throw new Error(`no record found for ${name}#${claimId}`);
      } else if(result.length !== 1) {
        logger.warn(`more than one record matches ${name}#${claimId} in db.Claim`);
      }

      return result[0].transaction_hash_id;
    });
  },

  getCurrentHeight: async () => {
    return await table
    .max('height')
    .then(result => {
      return (result || 100000);
    });
  },

})