'use strict';

var Manage = module.exports;
var sfs = require('safe-replace').create({ tmp: 'tmp', bak: 'bak' });
var promisify = require('util').promisify;
var fs = require('fs');
var readFile = promisify(fs.readFile);
var statFile = promisify(fs.stat);
var chmodFile = promisify(fs.chmod);
var homedir = require('os').homedir();
var path = require('path');
var mkdirp = promisify(require('@root/mkdirp'));

Manage.create = function(opts) {
	if (!opts) {
		opts = {};
	}
	if (!opts.configFile) {
		opts.configFile = '~/.config/greenlock/manager.json';
		console.info('Greenlock Manager Config File: ' + opts.configFile);
	}
	opts.configFile = opts.configFile.replace('~/', homedir + '/');

	var manage = {};

	manage._txPromise = Promise.resolve();

	manage.defaults = manage.config = function(conf) {
		// get / set default site settings such as
		// subscriberEmail, store, challenges, renewOffset, renewStagger
		return Manage._getLatest(manage, opts).then(function(config) {
			if (!conf) {
				conf = JSON.parse(JSON.stringify(config));
				delete conf.sites;
				return conf;
			}

			// TODO set initial sites
			if (conf.sites) {
				throw new Error('cannot set sites as global config');
			}

			// TODO whitelist rather than blacklist?
			if (
				[
					'subject',
					'altnames',
					'lastAttemptAt',
					'expiresAt',
					'issuedAt',
					'renewAt'
				].some(function(k) {
					if (k in conf) {
						throw new Error(
							'`' + k + '` not allowed as a default setting'
						);
					}
				})
			) {
			}

			Object.keys(conf).forEach(function(k) {
				if (-1 !== ['sites', 'module', 'manager'].indexOf(k)) {
					return;
				}

				if ('undefined' === typeof k) {
					throw new Error(
						"'" +
							k +
							"' should be set to a value, or `null`, but not left `undefined`"
					);
				}

				if (null === k) {
					delete config[k];
				}

				config[k] = conf[k];
			});

			return manage._save(config);
		});
	};

	manage.add = function(args) {
		manage._txPromise = manage._txPromise.then(function() {
			// if the fs has changed since we last wrote, get the lastest from disk
			return Manage._getLatest(manage, opts).then(function(config) {
				// TODO move to Greenlock.add
				var subscriberEmail = args.subscriberEmail;
				var subject = args.subject || args.domain;
				var primary = subject;
				var altnames =
					args.servernames || args.altnames || args.domains;
				if ('string' !== typeof primary) {
					if (!Array.isArray(altnames) || !altnames.length) {
						throw new Error('there needs to be a subject');
					}
					primary = altnames.slice(0).sort()[0];
				}
				if (!Array.isArray(altnames) || !altnames.length) {
					altnames = [primary];
				}
				primary = primary.toLowerCase();
				altnames = altnames.map(function(name) {
					return name.toLowerCase();
				});

				if (!config.sites) {
					config.sites = {};
				}

				var existing = config.sites[primary];
				var site = existing;
				if (!existing) {
					site = config.sites[primary] = { altnames: [primary] };
				}

				// The goal is to make this decently easy to manage by hand without mistakes
				// but also reasonably easy to error check and correct
				// and to make deterministic auto-corrections

				// TODO added, removed, moved (duplicate), changed
				if (subscriberEmail) {
					site.subscriberEmail = subscriberEmail;
				}
				site.subject = subject;
				site.renewAt = args.renewAt || site.renewAt || 0;
				if (
					altnames
						.slice(0)
						.sort()
						.join(' ') !== site.altnames.slice(0).sort().join(' ')
				) {
					// TODO signal to wait for renewal?
					// it will definitely be renewed on the first request anyway
					site.renewAt = 0;
				}
				site.altnames = altnames;
				if (!site.issuedAt) {
					site.issuedAt = 0;
				}
				site.expiresAt = site.expiresAt || 0;
				site.lastAttemptAt = site.lastAttemptAt || 0;
				// re-add if this was deleted
				site.deletedAt = 0;
				if (
					site.altnames
						.slice(0)
						.sort()
						.join() !==
					altnames
						.slice(0)
						.sort()
						.join()
				) {
					site.expiresAt = 0;
					site.issuedAt = 0;
				}

				// These should usually be empty, for most situations
				if (args.customerEmail) {
					site.customerEmail = args.customerEmail;
				}
				if (args.challenges) {
					site.challenges = args.challenges;
				}
				if (args.store) {
					site.store = args.store;
				}

				return manage._save(config).then(function() {
					return JSON.parse(JSON.stringify(site));
				});
			});
		});
		return manage._txPromise;
	};

	manage.find = function(args) {
		return _find(args).then(function(existing) {
			if (!opts.find) {
				return existing;
			}

			return Promise.resolve(opts.find(args)).then(function(results) {
				// TODO also detect and delete stale (just ignoring them for now)
				var changed = [];
				var same = [];
				results.forEach(function(_newer) {
					// Check lowercase subject names
					var subject = (_newer.subject || '').toLowerCase();
					// Set the default altnames to the subject, just in case
					var altnames = _newer.altnames || [];
					if (!altnames.includes(subject)) {
						console.warn(
							"all site configs should include 'subject' and 'altnames': " +
								subject
						);
						altnames.push(subject);
					}

					existing.some(function(_older) {
						if (subject !== (_older.subject || '').toLowerCase()) {
							return false;
						}
						_newer._exists = true;

						// Compare the altnames and update if needed
						if (
							altnames
								.slice(0)
								.sort()
								.join(' ') !==
							(_older.altnames || [])
								.slice(0)
								.sort()
								.join(' ')
						) {
							_older.renewAt = 0;
							_older.altnames = altnames;
							// TODO signal waitForRenewal (although it'll update on the first access automatically)
							changed.push(_older);
						} else {
							same.push(_older);
						}

						return true;
					});

					if (!_newer._exists) {
						changed.push({
							subject: subject,
							altnames: altnames,
							renewAt: 0
						});
					}
				});

				if (!changed.length) {
					return same;
				}

				// kinda redundant to pull again, but whatever...
				return Manage._getLatest(manage, opts).then(function(config) {
					changed.forEach(function(site) {
						config.sites[site.subject] = site;
					});
					return manage._save(config).then(function() {
						// everything was either added, updated, or not different
						// hence, this is everything
						var all = changed.concat(same);
						return all;
					});
				});
			});
		});
	};

	function _find(args) {
		return Manage._getLatest(manage, opts).then(function(config) {
			// i.e. find certs more than 30 days old
			//args.issuedBefore = Date.now() - 30 * 24 * 60 * 60 * 1000;
			// i.e. find certs more that will expire in less than 45 days
			//args.expiresBefore = Date.now() + 45 * 24 * 60 * 60 * 1000;
			var issuedBefore = args.issuedBefore || Infinity;
			var expiresBefore = args.expiresBefore || Infinity; //Date.now() + 21 * 24 * 60 * 60 * 1000;
			var all = !args.altnames;

			var altnames = (args.altnames || args.domains || []).slice(0);
			if (args.servername && !altnames.includes(args.servername)) {
				altnames.push(args.servername);
			}
			if (args.wildname && !altnames.includes(args.wildname)) {
				altnames.push(args.wildname);
			}

			// TODO match ANY domain on any cert
			var sites = Object.keys(config.sites || {})
				.filter(function(sub) {
					var site = config.sites[sub];
					if (site.deletedAt) {
						return false;
					}
					if (site.expiresAt >= expiresBefore) {
						return false;
					}
					if (site.issuedAt >= issuedBefore) {
						return false;
					}

					// if subject is specified, don't return anything else
					if (args.subject) {
						if (site.subject === args.subject) {
							return true;
						}
					}

					// altnames, servername, and wildname all get rolled into one
					return (
						all ||
						(site.altnames || []).some(function(name) {
							return altnames.includes(name);
						})
					);
				})
				.map(function(name) {
					var site = config.sites[name];
					return {
						subject: site.subject,
						altnames: site.altnames,
						issuedAt: site.issuedAt,
						expiresAt: site.expiresAt,
						renewOffset: site.renewOffset,
						renewStagger: site.renewStagger,
						renewAt: site.renewAt,
						subscriberEmail: site.subscriberEmail,
						customerEmail: site.customerEmail,
						challenges: site.challenges,
						store: site.store
					};
				});

			return sites;
		});
	}

	manage.notify = opts.notify || _notify;
	function _notify(ev, args) {
		if (!args) {
			args = ev;
			ev = args.event;
			delete args.event;
		}

		// TODO define message types
		if (!manage._notify_notice) {
			console.info(
				'set greenlockOptions.notify to override the default logger'
			);
			manage._notify_notice = true;
		}
		switch (ev) {
			case 'error':
			/* falls through */
			case 'warning':
				console.error(
					'Error%s:',
					(' ' + (args.context || '')).trimRight()
				);
				console.error(args.message);
				if (args.description) {
					console.error(args.description);
				}
				if (args.code) {
					console.error('code:', args.code);
				}
				break;
			default:
				if (/status/.test(ev)) {
					console.info(
						ev,
						args.altname || args.subject || '',
						args.status || ''
					);
					if (!args.status) {
						console.info(args);
					}
					break;
				}
				console.info(
					ev,
					'(more info available: ' + Object.keys(args).join(' ') + ')'
				);
		}
	}

	manage.update = function(args) {
		manage._txPromise = manage._txPromise.then(function() {
			return Manage._getLatest(manage, opts).then(function(config) {
				var site = config.sites[args.subject];
				//site.issuedAt = args.issuedAt;
				//site.expiresAt = args.expiresAt;
				site.renewAt = args.renewAt;
				return manage._save(config);
			});
		});
		return manage._txPromise;
	};

	manage.remove = function(args) {
		if (!args.subject) {
			throw new Error('should have a subject for sites to remove');
		}
		manage._txPromise = manage._txPromise.then(function() {
			return Manage._getLatest(manage, opts).then(function(config) {
				var site = config.sites[args.subject];
				if (!site) {
					return {};
				}
				site.deletedAt = Date.now();

				return JSON.parse(JSON.stringify(site));
			});
		});
		return manage._txPromise;
	};

	manage._lastStat = {
		size: 0,
		mtimeMs: 0
	};
	manage._config = {};

	manage._save = function(config) {
		return mkdirp(path.dirname(opts.configFile)).then(function() {
			return sfs
				.writeFileAsync(
					opts.configFile,
					// pretty-print the config file
					JSON.stringify(config, null, 2),
					'utf8'
				)
				.then(function() {
					// this file may contain secrets, so keep it safe
					return chmodFile(opts.configFile, parseInt('0600', 8))
						.catch(function() {
							/*ignore for Windows */
						})
						.then(function() {
							return statFile(opts.configFile).then(function(
								stat
							) {
								manage._lastStat.size = stat.size;
								manage._lastStat.mtimeMs = stat.mtimeMs;
							});
						});
				});
		});
	};

	return manage;
};

Manage._getLatest = function(mng, opts) {
	return statFile(opts.configFile)
		.catch(function(err) {
			if ('ENOENT' === err.code) {
				return {
					size: 0,
					mtimeMs: 0
				};
			}
			err.context = 'manager_read';
			throw err;
		})
		.then(function(stat) {
			if (
				stat.size === mng._lastStat.size &&
				stat.mtimeMs === mng._lastStat.mtimeMs
			) {
				return mng._config;
			}
			return readFile(opts.configFile, 'utf8').then(function(data) {
				mng._lastStat = stat;
				mng._config = JSON.parse(data);
				return mng._config;
			});
		});
};