'use strict'; const { coerce, lt, lte } = require('semver'); const browserslist = require('browserslist'); const data = require('./data'); const getModulesListForTargetVersion = require('./get-modules-list-for-target-version'); const has = Function.call.bind({}.hasOwnProperty);

const mapping = new Map([

['ios_saf', 'ios'],
['and_chr', 'chrome'],
['and_ff', 'firefox'],

]);

const validTargets = new Set([

'android',
'chrome',
'edge',
'electron',
'firefox',
'ie',
'ios',
'node',
'opera',
'phantom',
'safari',
'samsung',

]);

function coercedLte(a, b) {

return lte(coerce(a), coerce(b));

}

function coercedLt(a, b) {

return lt(coerce(a), coerce(b));

}

function normalizeBrowsersList(list) {

return list.map(it => {
  let [engine, version] = it.split(' ');
  if (mapping.has(engine)) engine = mapping.get(engine);
  else if (engine === 'android' && !coercedLte(version, '4.4.4')) engine = 'chrome';
  return [engine, version];
}).filter(([engine]) => validTargets.has(engine));

}

function reduceByMinVersion(list) {

const targets = new Map();
for (const [engine, version] of list) {
  if (!targets.has(engine) || coercedLte(version, targets.get(engine))) {
    targets.set(engine, version);
  }
}
return targets;

}

function checkModule(name, targets) {

if (!has(data, name)) throw new TypeError(`Incorrect module: ${ name }`);
const requirements = data[name];
const result = {
  required: false,
  targets: {},
};
for (const [engine, version] of targets) {
  if (!has(requirements, engine) || coercedLt(version, requirements[engine])) {
    result.required = true;
    result.targets[engine] = version;
  }
}
return result;

}

function compat({ targets, filter, version }) {

const list = browserslist(targets);
const engines = normalizeBrowsersList(list);
const reducedTargets = reduceByMinVersion(engines);

const result = {
  list: [],
  targets: {},
};

let modules = Array.isArray(filter) ? filter : Object.keys(data);

if (filter instanceof RegExp) modules = modules.filter(it => filter.test(it));
else if (typeof filter == 'string') modules = modules.filter(it => it.startsWith(filter));

if (version) {
  const availableModules = new Set(getModulesListForTargetVersion(version));
  modules = modules.filter(name => availableModules.has(name));
}

modules.forEach(key => {
  const check = checkModule(key, reducedTargets);
  if (check.required) {
    result.list.push(key);
    result.targets[key] = check.targets;
  }
});

return result;

}

module.exports = compat; module.exports.compat = compat; module.exports.getModulesListForTargetVersion = getModulesListForTargetVersion;