'use strict';
var _ = require('lodash');

var versionParts = ['major', 'minor', 'patch'];

function ResourceCache() {
  this.libs = {};

  this.storeRelease = function(release) {
    this.libs[release.libName] = this.libs[release.libName] || {};

    distributeIntoBucketsRecursive(0, this.libs[release.libName], release);
    distributeReleaseIntoTypes(this.libs[release.libName], release);
  };

  this.getReleases = function(releaseRequest) {
    return getFromBucketsRecursive(0, this.libs[releaseRequest.libName], releaseRequest);
  };
}

function distributeIntoBucketsRecursive(versionPartIndex, parent, release) {
  var versionPart = versionParts[versionPartIndex];
  if (!versionPart) {
    distributeReleaseIntoVersionSpecifiers(parent, release);
    return;
  }

  var value = release[versionPart];

  if (!parent[value]) {
    parent[value] = {};
  }

  distributeReleaseIntoTypes(parent[value], release);
  distributeIntoBucketsRecursive(versionPartIndex + 1, parent[value], release);
}

function distributeReleaseIntoVersionSpecifiers(parent, release) {
  if (release.preRelease) {
    if (!parent[release.preRelease]) {
      parent[release.preRelease] = {};
    }

    distributeReleaseIntoTypes(parent[release.preRelease], release);

    if (release.metadata) {
      if (!parent[release.preRelease][release.metadata]) {
        parent[release.preRelease][release.metadata] = {};
      }

      distributeReleaseIntoTypes(parent[release.preRelease][release.metadata], release);
    }
  }

  if (release.metadata) {
    if (!parent['no-prerelease']) {
      parent['no-prerelease'] = {};
    }

    if (!parent['no-prerelease'][release.metadata]) {
      parent['no-prerelease'][release.metadata] = {};
    }

    distributeReleaseIntoTypes(parent['no-prerelease'][release.metadata], release);
  }
}

function distributeReleaseIntoTypes(parent, release) {
  if (!parent['latest']) {
    parent['latest'] = {};
  }

  if (!parent['latest']['all']) {
    parent['latest']['all'] = {};
  }

  if (!parent['latest']['all'][release.resourceType]) {
    parent['latest']['all'][release.resourceType] = [release];
  }

  parent['latest'][release.resourceType] = [release];
}

function getFromBucketsRecursive(versionPartIndex, parent, releaseRequest) {
  var versionPart = versionParts[versionPartIndex];
  if (!versionPart) {
    return getReleasesFromVersionSpecifiers(parent, releaseRequest);
  }

  var value = releaseRequest[versionPart];
  if (!value) {
    return getReleasesOfType(parent, releaseRequest);
  }

  return getFromBucketsRecursive(versionPartIndex + 1, parent[value], releaseRequest);
}

function getReleasesFromVersionSpecifiers(parent, releaseRequest) {
  if (releaseRequest.preRelease) {
    if (releaseRequest.metadata) {
      return getReleasesOfType(parent[releaseRequest.preRelease][releaseRequest.metadata], releaseRequest);
    }
    return getReleasesOfType(parent[releaseRequest.preRelease], releaseRequest);
  }

  if (releaseRequest.metadata) {
    return getReleasesOfType(parent['no-prerelease'][releaseRequest.metadata], releaseRequest);
  }

  return getReleasesOfType(parent, releaseRequest);
}

function getReleasesOfType(parent, releaseRequest) {
  if (!parent || !parent['latest']) {
    return null;
  }

  if (releaseRequest.resourceType) {
    return parent['latest'][releaseRequest.resourceType];
  }

  return _.flatten(_.map(parent['latest']['all'], function(releases) {
    return releases;
  }));
}

module.exports = ResourceCache;