///<reference path="../../../headers/common.d.ts" />

import _ from 'lodash';
import {
  QueryPartDef,
  QueryPart,
  functionRenderer,
  suffixRenderer,
  identityRenderer,
  quotedIdentityRenderer,
} from 'app/core/components/query_part/query_part';

var index = [];
var categories = {
  Aggregations: [],
  Selectors: [],
  Transformations: [],
  Math: [],
  Aliasing: [],
  Fields: [],
};

function createPart(part): any {
  var def = index[part.type];
  if (!def) {
    throw {message: 'Could not find query part ' + part.type};
  }

  return new QueryPart(part, def);
};

function register(options: any) {
  index[options.type] = new QueryPartDef(options);
  options.category.push(index[options.type]);
}

var groupByTimeFunctions = [];

function aliasRenderer(part, innerExpr) {
  return innerExpr + ' AS ' + '"' + part.params[0] + '"';
}

function fieldRenderer(part, innerExpr) {
  if (part.params[0] === '*')  {
    return '*';
  }
  return '"' + part.params[0] + '"';
}

function replaceAggregationAddStrategy(selectParts, partModel) {
  // look for existing aggregation
  for (var i = 0; i < selectParts.length; i++) {
    var part = selectParts[i];
    if (part.def.category === categories.Aggregations) {
      selectParts[i] = partModel;
      return;
    }
    if (part.def.category === categories.Selectors) {
      selectParts[i] = partModel;
      return;
    }
  }

  selectParts.splice(1, 0, partModel);
}

function addTransformationStrategy(selectParts, partModel) {
  var i;
  // look for index to add transformation
  for (i = 0; i < selectParts.length; i++) {
    var part = selectParts[i];
    if (part.def.category === categories.Math  || part.def.category === categories.Aliasing) {
      break;
    }
  }

  selectParts.splice(i, 0, partModel);
}

function addMathStrategy(selectParts, partModel) {
  var partCount = selectParts.length;
  if (partCount > 0) {
    // if last is math, replace it
    if (selectParts[partCount-1].def.type === 'math') {
      selectParts[partCount-1] = partModel;
      return;
    }
    // if next to last is math, replace it
    if (selectParts[partCount-2].def.type === 'math') {
      selectParts[partCount-2] = partModel;
      return;
    } else if (selectParts[partCount-1].def.type === 'alias') { // if last is alias add it before
      selectParts.splice(partCount-1, 0, partModel);
      return;
    }
  }
  selectParts.push(partModel);
}

function addAliasStrategy(selectParts, partModel) {
  var partCount = selectParts.length;
  if (partCount > 0) {
    // if last is alias, replace it
    if (selectParts[partCount-1].def.type === 'alias') {
      selectParts[partCount-1] = partModel;
      return;
    }
  }
  selectParts.push(partModel);
}

function addFieldStrategy(selectParts, partModel, query) {
  // copy all parts
  var parts = _.map(selectParts, function(part: any) {
    return createPart({type: part.def.type, params: _.clone(part.params)});
  });

  query.selectModels.push(parts);
}

register({
  type: 'field',
  addStrategy: addFieldStrategy,
  category: categories.Fields,
  params: [{type: 'field', dynamicLookup: true}],
  defaultParams: ['value'],
  renderer: fieldRenderer,
});

// Aggregations
register({
  type: 'count',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'distinct',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'integral',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'mean',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'median',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'sum',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Aggregations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

// transformations

register({
  type: 'derivative',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [{ name: "duration", type: "interval", options: ['1s', '10s', '1m', '5m', '10m', '15m', '1h']}],
  defaultParams: ['10s'],
  renderer: functionRenderer,
});

register({
  type: 'spread',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'non_negative_derivative',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [{ name: "duration", type: "interval", options: ['1s', '10s', '1m', '5m', '10m', '15m', '1h']}],
  defaultParams: ['10s'],
  renderer: functionRenderer,
});

register({
  type: 'difference',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'moving_average',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [{ name: "window", type: "number", options: [5, 10, 20, 30, 40]}],
  defaultParams: [10],
  renderer: functionRenderer,
});

register({
  type: 'stddev',
  addStrategy: addTransformationStrategy,
  category: categories.Transformations,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'time',
  category: groupByTimeFunctions,
  params: [{ name: "interval", type: "time", options: ['auto', '1s', '10s', '1m', '5m', '10m', '15m', '1h'] }],
  defaultParams: ['auto'],
  renderer: functionRenderer,
});

register({
  type: 'fill',
  category: groupByTimeFunctions,
  params: [{ name: "fill", type: "string", options: ['none', 'null', '0', 'previous'] }],
  defaultParams: ['null'],
  renderer: functionRenderer,
});

// Selectors
register({
  type: 'bottom',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [{name: 'count', type: 'int'}],
  defaultParams: [3],
  renderer: functionRenderer,
});

register({
  type: 'first',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'last',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'max',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'min',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [],
  defaultParams: [],
  renderer: functionRenderer,
});

register({
  type: 'percentile',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [{name: 'nth', type: 'int'}],
  defaultParams: [95],
  renderer: functionRenderer,
});

register({
  type: 'top',
  addStrategy: replaceAggregationAddStrategy,
  category: categories.Selectors,
  params: [{name: 'count', type: 'int'}],
  defaultParams: [3],
  renderer: functionRenderer,
});

register({
  type: 'tag',
  category: groupByTimeFunctions,
  params: [{name: 'tag', type: 'string', dynamicLookup: true}],
  defaultParams: ['tag'],
  renderer: fieldRenderer,
});

register({
  type: 'math',
  addStrategy: addMathStrategy,
  category: categories.Math,
  params: [{ name: "expr", type: "string"}],
  defaultParams: [' / 100'],
  renderer: suffixRenderer,
});

register({
  type: 'alias',
  addStrategy: addAliasStrategy,
  category: categories.Aliasing,
  params: [{ name: "name", type: "string", quote: 'double'}],
  defaultParams: ['alias'],
  renderMode: 'suffix',
  renderer: aliasRenderer,
});


export default {
  create: createPart,
  getCategories: function() {
    return categories;
  }
};
