use std::{
	future::Future,
	pin::Pin,
	task::{Context, Poll},
};

use chrono::{DateTime, Utc};
use futures::future::BoxFuture;
use log::debug;
use serde::{Deserialize, Serialize, Serializer};
use snafu::{ResultExt, Snafu};

use super::ApiKey;

/// custom error type for the search endpoint
#[derive(Debug, Snafu)]
pub enum Error {
	#[snafu(display("failed to connect to the api: {}", string))]
	Connection { string: String },
	#[snafu(display("failed to deserialize: {} {}", string, source))]
	Deserialization {
		string: String,
		source: serde_json::Error,
	},
	#[snafu(display("failed to serialize: {}", source))]
	Serialization {
		source: serde_urlencoded::ser::Error,
	},
}

impl From<surf::Error> for Error {
	fn from(surf_error: surf::Error) -> Self {
		Error::Connection {
			string: surf_error.to_string(),
		}
	}
}

/// request struct for the search endpoint
pub struct SearchList {
	future: Option<BoxFuture<'static, Result<Response, Error>>>,
	data: Option<SearchListData>,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
struct SearchListData {
	key: ApiKey,
	part: String,
	#[serde(skip_serializing_if = "std::ops::Not::not")]
	for_content_owner: bool,
	#[serde(skip_serializing_if = "std::ops::Not::not")]
	for_developer: bool,
	#[serde(skip_serializing_if = "std::ops::Not::not")]
	for_mine: bool,
	#[serde(skip_serializing_if = "Option::is_none")]
	related_to_video_id: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	channel_id: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	channel_type: Option<ChannelType>,
	#[serde(skip_serializing_if = "Option::is_none")]
	event_type: Option<EventType>,
	#[serde(skip_serializing_if = "Option::is_none")]
	location: Option<VideoLocation>,
	#[serde(skip_serializing_if = "Option::is_none")]
	location_radius: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	max_results: Option<u8>,
	#[serde(skip_serializing_if = "Option::is_none")]
	on_behalf_of_content_owner: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	order: Option<Order>,
	#[serde(skip_serializing_if = "Option::is_none")]
	page_token: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	published_after: Option<DateTime<Utc>>,
	#[serde(skip_serializing_if = "Option::is_none")]
	published_before: Option<DateTime<Utc>>,
	#[serde(skip_serializing_if = "Option::is_none")]
	q: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	region_code: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	relevance_language: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	safe_search: Option<SafeSearch>,
	#[serde(skip_serializing_if = "Option::is_none")]
	topic_id: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none", rename = "type")]
	item_type: Option<ItemType>,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_caption: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_category_id: Option<String>,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_definition: Option<VideoDefinition>,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_dimension: Option<VideoDimension>,
	#[serde(skip_serializing_if = "std::ops::Not::not")]
	video_embeddable: bool,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_license: Option<VideoLicense>,
	#[serde(skip_serializing_if = "std::ops::Not::not")]
	video_syndicated: bool,
	#[serde(skip_serializing_if = "Option::is_none")]
	video_type: Option<VideoType>,
}

impl SearchList {
	const URL: &'static str = "https://www.googleapis.com/youtube/v3/search";

	/// create struct with an [`ApiKey`](../struct.ApiKey.html)
	#[must_use]
	pub fn new(key: ApiKey) -> Self {
		Self {
			future: None,
			data: Some(SearchListData {
				key,
				part: String::from("snippet"),
				for_content_owner: false,
				for_developer: false,
				for_mine: false,
				related_to_video_id: None,
				channel_id: None,
				channel_type: None,
				event_type: None,
				location: None,
				location_radius: None,
				max_results: None,
				on_behalf_of_content_owner: None,
				order: None,
				page_token: None,
				published_after: None,
				published_before: None,
				q: None,
				region_code: None,
				relevance_language: None,
				safe_search: None,
				topic_id: None,
				item_type: None,
				video_caption: None,
				video_category_id: None,
				video_definition: None,
				video_dimension: None,
				video_embeddable: false,
				video_license: None,
				video_syndicated: false,
				video_type: None,
			}),
		}
	}

	#[must_use]
	pub fn for_content_owner(mut self) -> Self {
		let mut data = self.data.take().unwrap();
		data.for_content_owner = true;
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn for_developer(mut self) -> Self {
		let mut data = self.data.take().unwrap();
		data.for_developer = true;
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn for_mine(mut self) -> Self {
		let mut data = self.data.take().unwrap();
		data.for_mine = true;
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn related_to_video_id(mut self, related_to_video_id: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.related_to_video_id = Some(related_to_video_id.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn channel_id(mut self, channel_id: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.channel_id = Some(channel_id.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn channel_type(mut self, channel_type: impl Into<ChannelType>) -> Self {
		let mut data = self.data.take().unwrap();
		data.channel_type = Some(channel_type.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn event_type(mut self, event_type: impl Into<EventType>) -> Self {
		let mut data = self.data.take().unwrap();
		data.event_type = Some(event_type.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn location(mut self, location: impl Into<VideoLocation>) -> Self {
		let mut data = self.data.take().unwrap();
		data.location = Some(location.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn location_radius(mut self, location_radius: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.location_radius = Some(location_radius.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn max_results(mut self, max_results: impl Into<u8>) -> Self {
		let mut data = self.data.take().unwrap();
		data.max_results = Some(max_results.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn on_behalf_of_content_owner(
		mut self,
		on_behalf_of_content_owner: impl Into<String>,
	) -> Self {
		let mut data = self.data.take().unwrap();
		data.on_behalf_of_content_owner = Some(on_behalf_of_content_owner.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn order(mut self, order: impl Into<Order>) -> Self {
		let mut data = self.data.take().unwrap();
		data.order = Some(order.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn page_token(mut self, page_token: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.page_token = Some(page_token.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn published_after(mut self, published_after: impl Into<DateTime<Utc>>) -> Self {
		let mut data = self.data.take().unwrap();
		data.published_after = Some(published_after.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn published_before(mut self, published_before: impl Into<DateTime<Utc>>) -> Self {
		let mut data = self.data.take().unwrap();
		data.published_before = Some(published_before.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn q(mut self, q: impl Into<String>) -> Self {
		let mut data = self.data.unwrap();
		data.q = Some(q.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn region_code(mut self, region_code: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.region_code = Some(region_code.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn relevance_language(mut self, relevance_language: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.relevance_language = Some(relevance_language.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn safe_search(mut self, safe_search: impl Into<SafeSearch>) -> Self {
		let mut data = self.data.take().unwrap();
		data.safe_search = Some(safe_search.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn topic_id(mut self, topic_id: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.topic_id = Some(topic_id.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn item_type(mut self, item_type: impl Into<ItemType>) -> Self {
		let mut data = self.data.take().unwrap();
		data.item_type = Some(item_type.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_caption(mut self, video_caption: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_caption = Some(video_caption.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_category_id(mut self, video_category_id: impl Into<String>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_category_id = Some(video_category_id.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_definition(mut self, video_definition: impl Into<VideoDefinition>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_definition = Some(video_definition.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_dimension(mut self, video_dimension: impl Into<VideoDimension>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_dimension = Some(video_dimension.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_embeddable(mut self) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_embeddable = true;
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_license(mut self, video_license: impl Into<VideoLicense>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_license = Some(video_license.into());
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_syndicated(mut self) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_syndicated = true;
		self.data = Some(data);
		self
	}

	#[must_use]
	pub fn video_type(mut self, video_type: impl Into<VideoType>) -> Self {
		let mut data = self.data.take().unwrap();
		data.video_type = Some(video_type.into());
		self.data = Some(data);
		self
	}
}

impl Future for SearchList {
	type Output = Result<Response, Error>;

	fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
		if self.future.is_none() {
			let data = self.data.take().unwrap();
			self.future = Some(Box::pin(async move {
				let url = format!(
					"{}?{}",
					Self::URL,
					serde_urlencoded::to_string(&data).context(Serialization)?
				);
				debug!("getting {}", url);
				let response = surf::get(&url).recv_string().await?;
				serde_json::from_str(&response)
					.with_context(move || Deserialization { string: response })
			}));
		}

		self.future.as_mut().unwrap().as_mut().poll(cx)
	}
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum ChannelType {
	Any,
	Show,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum EventType {
	Completed,
	Live,
	Upcoming,
}

#[derive(Debug, Clone)]
pub struct VideoLocation {
	longitude: f32,
	latitude: f32,
}

impl VideoLocation {
	#[must_use]
	pub fn new(longitude: f32, latitude: f32) -> Self {
		Self {
			longitude,
			latitude,
		}
	}
}

impl Serialize for VideoLocation {
	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
	where
		S: Serializer,
	{
		serializer.serialize_str(&format!("{},{}", self.longitude, self.latitude))
	}
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum Order {
	Date,
	Rating,
	Relevance,
	Title,
	VideoCount,
	ViewCount,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum SafeSearch {
	Moderate,
	Strict,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum ItemType {
	Channel,
	Playlist,
	Video,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum VideoCaption {
	ClosedCaption,
	None,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum VideoDefinition {
	High,
	Standard,
}

#[derive(Debug, Clone, Serialize)]
pub enum VideoDimension {
	#[serde(rename = "3d")]
	Three,
	#[serde(rename = "2d")]
	Two,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum VideoDuration {
	Long,
	Medium,
	Short,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum VideoLicense {
	CreativeCommon,
	Youtube,
}

#[derive(Debug, Clone, Serialize)]
#[serde(rename_all = "camelCase")]
pub enum VideoType {
	Episode,
	Movie,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct Response {
	pub kind: String,
	pub etag: String,
	pub prev_page_token: Option<String>,
	pub region_code: String,
	pub page_info: PageInfo,
	pub items: Vec<SearchResult>,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct PageInfo {
	pub total_results: i64,
	pub results_per_page: i64,
}

#[derive(Debug, Clone, Deserialize)]
pub struct SearchResult {
	pub kind: String,
	pub etag: String,
	pub id: Id,
	pub snippet: Snippet,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct Id {
	pub kind: String,
	pub video_id: Option<String>,
	pub channel_id: Option<String>,
	pub playlist_id: Option<String>,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct Snippet {
	pub published_at: Option<DateTime<Utc>>,
	pub channel_id: Option<String>,
	pub title: Option<String>,
	pub description: Option<String>,
	pub thumbnails: Option<Thumbnails>,
	pub channel_title: Option<String>,
	pub live_broadcast_content: Option<String>,
}

#[derive(Debug, Clone, Deserialize)]
pub struct Thumbnails {
	pub default: Option<Thumbnail>,
	pub medium: Option<Thumbnail>,
	pub high: Option<Thumbnail>,
	pub standard: Option<Thumbnail>,
	pub maxres: Option<Thumbnail>,
}

#[derive(Debug, Clone, Deserialize)]
pub struct Thumbnail {
	pub url: String,
	pub width: Option<u64>,
	pub height: Option<u64>,
}