const mm_client = (function() { "use strict";


class MattermostApi {
	constructor(endpoint) {
		this._endpoint = endpoint;
	}

	get id() {
		return this._endpoint;
	}

	async get(path, token, queryParams) {
		const headers = token ? {"Authorization": `Bearer ${token}`} : {};
		const response = await ajax.getJson(`${this._endpoint}${path}`, {headers, queryParams});
		if (!response.ok) {
			throw response;
		}
		return response;
	}

	async post(path, token, data) {
		const headers = token ? {"Authorization": `Bearer ${token}`} : {};
		const response = await ajax.postJson(`${this._endpoint}${path}`, data, {headers});
		if (!response.ok) {
			throw response;
		}
		return response;
	}
}


class MattermostClient {
	constructor (api) {
		this.api = api;
	}

	async logIn(login_id, password) {
		const response = await this.api.post("/users/login", undefined, {login_id, password});
		const token = response.getResponseHeader("Token");
		if (!token) {
			throw Error("No Token header in response to log in request");
		}
		credentials.store(this.api.id, login_id, token);
		return response.responseJson;
	}

	async logOut() {
		const stored = credentials.get(this.api.id);
		if (!stored || !stored.token) {
			throw Error("No token stored");
		}
		const response = await this.api.post("/users/logout", stored.token);

		// Verify that the token is now invalidated
		let tokenWorks;
		try {
			const meResponse = await this.usersMe();
			tokenWorks = true;
		} catch (e) {
			if (e instanceof ajax.NotOkError && e.xhr.status == 401) {
				tokenWorks = false;
			} else {
				throw e;
			}
		}
		if (tokenWorks) {
			throw new Error("Failed to log out: token still works after trying to log out");
		}

		credentials.clear(this.api.id);
		return response.responseJson;
	}

	async usersMe() {
		const stored = credentials.get(this.api.id);
		if (!stored || !stored.token) {
			throw Error("No token stored");
		}
		const response = await this.api.get("/users/me", stored.token);
		return response.responseJson;
	}

	async myTeams() {
		const stored = credentials.get(this.api.id);
		const response = await this.api.get("/users/me/teams", stored.token);
		return response.responseJson;
	}

	async myChannels(team_id) {
		const stored = credentials.get(this.api.id);
		const response = await this.api.get(`/users/me/teams/${team_id}/channels`, stored.token);
		return response.responseJson;
	}

	async channelPosts(channel_id, beforePost=null, afterPost=null, since=null) {
		const stored = credentials.get(this.api.id);
		const response = await this.api.get(`/channels/${channel_id}/posts`, stored.token, {
			before: beforePost, after: afterPost, since
		});
		return response.responseJson;
	}
}

return {MattermostApi, MattermostClient};

})();