use crate::database::Storage;
use kittybox_indieauth::TokenData;
use chrono::prelude::*;
use core::iter::Iterator;
use newbase60::num_to_sxg;
use serde_json::json;
use std::convert::TryInto;

pub(crate) const DEFAULT_CHANNEL_PATH: &str = "/feeds/main";
const DEFAULT_CHANNEL_NAME: &str = "Main feed";
pub(crate) const CONTACTS_CHANNEL_PATH: &str = "/feeds/vcards";
const CONTACTS_CHANNEL_NAME: &str = "My address book";
pub(crate) const FOOD_CHANNEL_PATH: &str = "/feeds/food";
const FOOD_CHANNEL_NAME: &str = "My recipe book";

fn get_folder_from_type(post_type: &str) -> String {
    (match post_type {
        "h-feed" => "feeds/",
        "h-card" => "vcards/",
        "h-event" => "events/",
        "h-food" => "food/",
        _ => "posts/",
    })
    .to_string()
}

/// Reset the datetime to a proper datetime.
/// Do not attempt to recover the information.
/// Do not pass GO. Do not collect $200.                
fn reset_dt(post: &mut serde_json::Value) -> DateTime<FixedOffset> {
    let curtime: DateTime<Local> = Local::now();
    post["properties"]["published"] = json!([curtime.to_rfc3339()]);
    chrono::DateTime::from(curtime)
}

pub fn normalize_mf2(mut body: serde_json::Value, user: &TokenData) -> (String, serde_json::Value) {
    // Normalize the MF2 object here.
    let me = &user.me;
    let folder = get_folder_from_type(body["type"][0].as_str().unwrap());
    let published: DateTime<FixedOffset> =
        if let Some(dt) = body["properties"]["published"][0].as_str() {
            // Check if the datetime is parsable.
            match DateTime::parse_from_rfc3339(dt) {
                Ok(dt) => dt,
                Err(_) => reset_dt(&mut body),
            }
        } else {
            // Set the datetime.
            // Note: this code block duplicates functionality with the above failsafe.
            // Consider refactoring it to a helper function?
            reset_dt(&mut body)
        };
    match body["properties"]["uid"][0].as_str() {
        None => {
            let uid = serde_json::Value::String(
                me.join(
                    &(folder.clone()
                        + &num_to_sxg(published.timestamp_millis().try_into().unwrap())),
                )
                .unwrap()
                .to_string(),
            );
            body["properties"]["uid"] = serde_json::Value::Array(vec![uid.clone()]);
            match body["properties"]["url"].as_array_mut() {
                Some(array) => array.push(uid),
                None => body["properties"]["url"] = body["properties"]["uid"].clone(),
            }
        }
        Some(uid_str) => {
            let uid = uid_str.to_string();
            match body["properties"]["url"].as_array_mut() {
                Some(array) => {
                    if !array.iter().any(|i| i.as_str().unwrap_or("") == uid) {
                        array.push(serde_json::Value::String(uid))
                    }
                }
                None => body["properties"]["url"] = body["properties"]["uid"].clone(),
            }
        }
    }
    if let Some(slugs) = body["properties"]["mp-slug"].as_array() {
        let new_urls = slugs
            .iter()
            .map(|i| i.as_str().unwrap_or(""))
            .filter(|i| i != &"")
            .map(|i| me.join(&((&folder).clone() + i)).unwrap().to_string())
            .collect::<Vec<String>>();
        let urls = body["properties"]["url"].as_array_mut().unwrap();
        new_urls.iter().for_each(|i| urls.push(json!(i)));
    }
    let props = body["properties"].as_object_mut().unwrap();
    props.remove("mp-slug");

    if body["properties"]["content"][0].is_string() {
        // Convert the content to HTML using the `markdown` crate
        body["properties"]["content"] = json!([{
            "html": markdown::to_html(body["properties"]["content"][0].as_str().unwrap()),
            "value": body["properties"]["content"][0]
        }])
    }
    // TODO: apply this normalization to editing too
    if body["properties"]["mp-channel"].is_array() {
        let mut additional_channels = body["properties"]["mp-channel"].as_array().unwrap().clone();
        if let Some(array) = body["properties"]["channel"].as_array_mut() {
            array.append(&mut additional_channels);
        } else {
            body["properties"]["channel"] = json!(additional_channels)
        }
        body["properties"]
            .as_object_mut()
            .unwrap()
            .remove("mp-channel");
    } else if body["properties"]["mp-channel"].is_string() {
        let chan = body["properties"]["mp-channel"]
            .as_str()
            .unwrap()
            .to_owned();
        if let Some(array) = body["properties"]["channel"].as_array_mut() {
            array.push(json!(chan))
        } else {
            body["properties"]["channel"] = json!([chan]);
        }
        body["properties"]
            .as_object_mut()
            .unwrap()
            .remove("mp-channel");
    }
    if body["properties"]["channel"][0].as_str().is_none() {
        match body["type"][0].as_str() {
            Some("h-entry") => {
                // Set the channel to the main channel...
                // TODO find like posts and move them to separate private channel
                let default_channel = me.join(DEFAULT_CHANNEL_PATH).unwrap().to_string();

                body["properties"]["channel"] = json!([default_channel]);
            }
            Some("h-card") => {
                let default_channel = me.join(CONTACTS_CHANNEL_PATH).unwrap().to_string();

                body["properties"]["channel"] = json!([default_channel]);
            }
            Some("h-food") => {
                let default_channel = me.join(FOOD_CHANNEL_PATH).unwrap().to_string();

                body["properties"]["channel"] = json!([default_channel]);
            }
            // TODO h-event
            /*"h-event" => {
                let default_channel
            },*/
            _ => {
                body["properties"]["channel"] = json!([]);
            }
        }
    }
    body["properties"]["posted-with"] = json!([user.client_id]);
    if body["properties"]["author"][0].as_str().is_none() {
        body["properties"]["author"] = json!([me.as_str()])
    }
    // TODO: maybe highlight #hashtags?
    // Find other processing to do and insert it here
    return (
        body["properties"]["uid"][0].as_str().unwrap().to_string(),
        body,
    );
}

pub(crate) fn form_to_mf2_json(form: Vec<(String, String)>) -> serde_json::Value {
    let mut mf2 = json!({"type": [], "properties": {}});
    for (k, v) in form {
        if k == "h" {
            mf2["type"]
                .as_array_mut()
                .unwrap()
                .push(json!("h-".to_string() + &v));
        } else if k != "access_token" {
            let key = k.strip_suffix("[]").unwrap_or(&k);
            match mf2["properties"][key].as_array_mut() {
                Some(prop) => prop.push(json!(v)),
                None => mf2["properties"][key] = json!([v]),
            }
        }
    }
    if mf2["type"].as_array().unwrap().is_empty() {
        mf2["type"].as_array_mut().unwrap().push(json!("h-entry"));
    }
    mf2
}

pub(crate) async fn create_feed(
    storage: &impl Storage,
    uid: &str,
    channel: &str,
    user: &TokenData,
) -> crate::database::Result<()> {
    let path = url::Url::parse(channel).unwrap().path().to_string();

    let name = match path.as_str() {
        DEFAULT_CHANNEL_PATH => DEFAULT_CHANNEL_NAME,
        CONTACTS_CHANNEL_PATH => CONTACTS_CHANNEL_NAME,
        FOOD_CHANNEL_PATH => FOOD_CHANNEL_NAME,
        _ => panic!("Tried to create an unknown default feed!"),
    };

    let (_, feed) = normalize_mf2(
        json!({
            "type": ["h-feed"],
            "properties": {
                "name": [name],
                "uid": [channel]
            },
            "children": [uid]
        }),
        user,
    );
    storage.put_post(&feed, user.me.as_str()).await
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    fn token_data() -> TokenData {
        TokenData {
            me: "https://fireburn.ru/".parse().unwrap(),
            client_id: "https://quill.p3k.io/".parse().unwrap(),
            scope: kittybox_indieauth::Scopes::new(vec![kittybox_indieauth::Scope::Create]),
            exp: Some(u64::MAX),
            iat: Some(0)
        }
    }

    #[test]
    fn test_form_to_mf2() {
        assert_eq!(
            super::form_to_mf2_json(
                serde_urlencoded::from_str("h=entry&content=something%20interesting").unwrap()
            ),
            json!({
                "type": ["h-entry"],
                "properties": {
                    "content": ["something interesting"]
                }
            })
        )
    }

    #[test]
    fn test_no_replace_uid() {
        let mf2 = json!({
            "type": ["h-card"],
            "properties": {
                "uid": ["https://fireburn.ru/"],
                "name": ["Vika Nezrimaya"],
                "note": ["A crazy programmer girl who wants some hugs"]
            }
        });

        let (uid, normalized) = normalize_mf2(
            mf2.clone(),
            &token_data(),
        );
        assert_eq!(
            normalized["properties"]["uid"][0], mf2["properties"]["uid"][0],
            "UID was replaced"
        );
        assert_eq!(
            normalized["properties"]["uid"][0], uid,
            "Returned post location doesn't match UID"
        );
    }

    #[test]
    fn test_mp_channel() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "uid": ["https://fireburn.ru/posts/test"],
                "content": [{"html": "<p>Hello world!</p>"}],
                "mp-channel": ["https://fireburn.ru/feeds/test"]
            }
        });

        let (_, normalized) = normalize_mf2(
            mf2.clone(),
            &token_data(),
        );

        assert_eq!(
            normalized["properties"]["channel"],
            mf2["properties"]["mp-channel"]
        );
    }

    #[test]
    fn test_mp_channel_as_string() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "uid": ["https://fireburn.ru/posts/test"],
                "content": [{"html": "<p>Hello world!</p>"}],
                "mp-channel": "https://fireburn.ru/feeds/test"
            }
        });

        let (_, normalized) = normalize_mf2(
            mf2.clone(),
            &token_data(),
        );

        assert_eq!(
            normalized["properties"]["channel"][0],
            mf2["properties"]["mp-channel"]
        );
    }

    #[test]
    fn test_normalize_mf2() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "content": ["This is content!"]
            }
        });

        let (uid, post) = normalize_mf2(
            mf2,
            &token_data(),
        );
        assert_eq!(
            post["properties"]["published"]
                .as_array()
                .expect("post['published'] is undefined")
                .len(),
            1,
            "Post doesn't have a published time"
        );
        DateTime::parse_from_rfc3339(post["properties"]["published"][0].as_str().unwrap())
            .expect("Couldn't parse date from rfc3339");
        assert!(
            !post["properties"]["url"]
                .as_array()
                .expect("post['url'] is undefined")
                .is_empty(),
            "Post doesn't have any URLs"
        );
        assert_eq!(
            post["properties"]["uid"]
                .as_array()
                .expect("post['uid'] is undefined")
                .len(),
            1,
            "Post doesn't have a single UID"
        );
        assert_eq!(
            post["properties"]["uid"][0], uid,
            "UID of a post and its supposed location don't match"
        );
        assert!(
            uid.starts_with("https://fireburn.ru/posts/"),
            "The post namespace is incorrect"
        );
        assert_eq!(
            post["properties"]["content"][0]["html"]
                .as_str()
                .expect("Post doesn't have a rich content object")
                .trim(),
            "<p>This is content!</p>",
            "Parsed Markdown content doesn't match expected HTML"
        );
        assert_eq!(
            post["properties"]["channel"][0], "https://fireburn.ru/feeds/main",
            "Post isn't posted to the main channel"
        );
        assert_eq!(
            post["properties"]["author"][0], "https://fireburn.ru/",
            "Post author is unknown"
        );
    }

    #[test]
    fn test_mp_slug() {
        let mf2 = json!({
            "type": ["h-entry"],
            "properties": {
                "content": ["This is content!"],
                "mp-slug": ["hello-post"]
            },
        });

        let (_, post) = normalize_mf2(
            mf2,
            &token_data(),
        );
        assert!(
            post["properties"]["url"]
                .as_array()
                .unwrap()
                .iter()
                .map(|i| i.as_str().unwrap())
                .any(|i| i == "https://fireburn.ru/posts/hello-post"),
            "Didn't found an URL pointing to the location expected by the mp-slug semantics"
        );
        assert!(
            post["properties"]["mp-slug"].as_array().is_none(),
            "mp-slug wasn't deleted from the array!"
        )
    }

    #[test]
    fn test_normalize_feed() {
        let mf2 = json!({
            "type": ["h-feed"],
            "properties": {
                "name": "Main feed",
                "mp-slug": ["main"]
            }
        });

        let (uid, post) = normalize_mf2(
            mf2,
            &token_data(),
        );
        assert_eq!(
            post["properties"]["uid"][0], uid,
            "UID of a post and its supposed location don't match"
        );
        assert_eq!(post["properties"]["author"][0], "https://fireburn.ru/");
        assert!(
            post["properties"]["url"]
                .as_array()
                .unwrap()
                .iter()
                .map(|i| i.as_str().unwrap())
                .any(|i| i == "https://fireburn.ru/feeds/main"),
            "Didn't found an URL pointing to the location expected by the mp-slug semantics"
        );
        assert!(
            post["properties"]["mp-slug"].as_array().is_none(),
            "mp-slug wasn't deleted from the array!"
        )
    }
}