/*
This file is part of »munin«.

Copyright 2025 'Fenris Wolf' <fenris@folksprak.org>

»munin« is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

»munin« is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License
along with »munin«. If not, see <http://www.gnu.org/licenses/>.
 */


namespace _munin
{
	
	/**
	 */
	async function run_iteration(
		conf : _munin.conf.type_conf,
		sources : Array<_munin.type_source>,
		targets : Array<_munin.type_target>,
		{
			"dry_run": dry_run = false,
		} : {
			dry_run ?: boolean;
		} = {
		}
	) : Promise<void>
	{
		const now : lib_plankton.pit.type_pit = lib_plankton.pit.now();
		const events : Array<_munin.type_event> = (
			(await Promise.all(sources.map(source => source.fetch())))
			.reduce((x, y) => x.concat(y), [])
		);
		for (const target of targets) {
			lib_plankton.log._info(
				"munin.run.iteration",
				{
					"details": {
						"target": target,
					}
				}
			);
			for (const hours of target.reminders) {
				const window_from : lib_plankton.pit.type_pit = lib_plankton.pit.shift_hour(
					now,
					hours + 0
				);
				const window_to : lib_plankton.pit.type_pit = lib_plankton.pit.shift_hour(
					now,
					hours + conf.settings.interval
				);
				for (const event of events) {
					const event_begin : lib_plankton.pit.type_pit = lib_plankton.pit.from_datetime(event.begin);
					lib_plankton.log._debug(
						"munin.run.check_dueness",
						{
							"details": {
								// "now": lib_plankton.pit.to_date_object(now).toISOString(),
								"event_begin": lib_plankton.pit.to_date_object(event_begin).toISOString(),
								"window_from": lib_plankton.pit.to_date_object(window_from).toISOString(),
								"window_to": lib_plankton.pit.to_date_object(window_to).toISOString(),
							}
						}
					);
					const remind : boolean = lib_plankton.pit.is_between(
						event_begin,
						window_from,
						window_to
					);
					if (! remind) {
						// do nothing
					}
					else {
						lib_plankton.log._info(
							"munin.remind",
							{
								"details": {
									"event": event,
									"target": target.show(),
								}
							}
						);
						if (dry_run) {
							// do nothing
						}
						else {
							await target.send(conf.labels, event);
						}
					}
				}
			}
		}
	}
	
	
	/**
	 */
	async function run(
		conf : _munin.conf.type_conf,
		{
			"single_run": single_run = false,
			"dry_run": dry_run = false,
		} : {
			single_run ?: boolean;
			dry_run ?: boolean;
		} = {
		}
	) : Promise<void>
	{
		const sources : Array<_munin.type_source> = conf.sources.map(
			source_raw => _munin.sources.factory(source_raw)
		);
		const targets : Array<_munin.type_target> = conf.targets.map(
			target_raw => _munin.targets.factory(target_raw)
		);
		lib_plankton.log._info(
			"munin.run.start",
			{
				"details": {
				}
			}
		);
		if (single_run) {
			await run_iteration(conf, sources, targets, {"dry_run": dry_run});
		}
		else {
			while (true) {
				await run_iteration(conf, sources, targets, {"dry_run": dry_run});
				await lib_plankton.call.sleep(conf.settings.interval * 60 * 60);
			}
		}
	}
	
	
	/**
	 */
	export async function main(
		args_raw : Array<string>
	): Promise<void>
	{
		// args
		const arg_handler : lib_plankton.args.class_handler = new lib_plankton.args.class_handler(
			{
				/*
				"action": lib_plankton.args.class_argument.positional({
					"index": 0,
					"type": lib_plankton.args.enum_type.string,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": "run",
					"info": "what to do : help | run",
					"name": "action",
				}),
				 */
				"conf_path": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["conf-path"],
					"indicators_short": ["c"],
					"type": lib_plankton.args.enum_type.string,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": "munin.json",
					"info": "path to configuration file",
					"name": "conf-path",
				}),
				"conf_expose": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["conf-expose"],
					"indicators_short": ["e"],
					"type": lib_plankton.args.enum_type.boolean,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": false,
					"info": "whether to expose the full configuration",
					"name": "conf-expose",
				}),
				"single_run": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["single-run"],
					"indicators_short": ["s"],
					"type": lib_plankton.args.enum_type.boolean,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": false,
					"info": "whether to only execute on iteration at run",
					"name": "single-run",
				}),
				"verbosity": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["verbosity"],
					"indicators_short": ["v"],
					"type": lib_plankton.args.enum_type.string,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": "notice",
					"info": "error | warning | notice | info | debug",
					"name": "verbosity",
				}),
				"dry_run": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["dry-run"],
					"indicators_short": ["q"],
					"type": lib_plankton.args.enum_type.boolean,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": false,
					"info": "whether to not skip the sending of reminders (logs will be written)",
					"name": "dry-run",
				}),
				"help": lib_plankton.args.class_argument.volatile({
					"indicators_long": ["help"],
					"indicators_short": ["h"],
					"type": lib_plankton.args.enum_type.boolean,
					"mode": lib_plankton.args.enum_mode.replace,
					"default": false,
					"info": "alias for action 'help'",
					"name": "help",
				}),
			}
		);
		const args : Record<string, any> = arg_handler.read(
			lib_plankton.args.enum_environment.cli,
			args_raw.join(" ")
		);
		
		if (args.help) {
			process.stdout.write(
				arg_handler.generate_help(
					{
						"programname": "munin",
						"description": "sends reminders about upcoming events",
						"executable": "node build/munin",
					}
				)
			);
		}
		else {
			// init
			const conf : _munin.conf.type_conf = await _munin.conf.load(args.conf_path);
			lib_plankton.log.set_main_logger(
				[
					{
						"kind": "filtered",
						"data": {
							"core": {
								"kind": "std",
								"data": {
									"target": "stdout",
									"format": {
										"kind": "human_readable",
										"data": {
										}
									}
								}
							},
							"predicate": [
								[
									{
										"item": {
											"kind": "level",
											"data": {
												"threshold": args.verbosity,
											}
										},
									},
								]
							],
						}
					},
				]
			);
			
			// exec
			if (args.conf_expose) {
				process.stdout.write(
					lib_plankton.json.encode(
						conf,
						{
							"formatted": true,
						}
					)
					+
					"\n"
				);
			}
			switch (/*args.action*/"run") {
				default: {
					throw (new Error("unhandled action: " + args.action));
					break;
				}
				case "run": {
					run(
						conf,
						{
							"single_run": args.single_run,
							"dry_run": args.dry_run,
						}
					);
					break;
				}
			}
		}

		return Promise.resolve<void>(undefined);
	}
}

_munin.main(process.argv.slice(2))
	.then(() => {})
	.catch((reason) => {process.stderr.write(String(reason) + "\n");})
;