mod branch;
mod load;
pub mod status;
pub mod webhook;

#[cfg(test)]
mod tests;

use std::time::Duration;

use actix::prelude::*;
use config::RegisteredWebhook;
use git::validation::positions::{validate_positions, Positions};

use crate as repo_actor;
use git_next_config as config;
use git_next_forge as forge;
use git_next_git as git;

use kxio::network::Network;
use tracing::{debug, info, warn, Instrument};

#[derive(Debug, derive_more::Display)]
#[display("{}:{}:{}", generation, repo_details.forge.forge_alias(), repo_details.repo_alias)]
pub struct RepoActor {
    generation: git::Generation,
    message_token: MessageToken,
    repo_details: git::RepoDetails,
    webhook: config::server::Webhook,
    webhook_id: Option<config::WebhookId>, // INFO: if [None] then no webhook is configured
    webhook_auth: Option<config::WebhookAuth>, // INFO: if [None] then no webhook is configured
    last_main_commit: Option<git::Commit>,
    last_next_commit: Option<git::Commit>,
    last_dev_commit: Option<git::Commit>,
    repository: git::Repository,
    open_repository: Option<git::OpenRepository>,
    net: Network,
    forge: forge::Forge,
}
impl RepoActor {
    pub fn new(
        details: git::RepoDetails,
        webhook: config::server::Webhook,
        generation: git::Generation,
        net: Network,
        repo: git::Repository,
    ) -> Self {
        let forge = match details.forge.forge_type() {
            #[cfg(feature = "forgejo")]
            config::ForgeType::ForgeJo => forge::Forge::new_forgejo(details.clone(), net.clone()),
            config::ForgeType::GitHub => forge::Forge::new_github(details.clone(), net.clone()),
            config::ForgeType::MockForge => forge::Forge::new_mock(),
        };
        debug!(?forge, "new");
        Self {
            generation,
            message_token: MessageToken::new(),
            repo_details: details,
            webhook,
            webhook_id: None,
            webhook_auth: None,
            last_main_commit: None,
            last_next_commit: None,
            last_dev_commit: None,
            repository: repo,
            open_repository: None,
            net,
            forge,
        }
    }
}
impl Actor for RepoActor {
    type Context = Context<Self>;
    #[tracing::instrument(name = "RepoActor::stopping", skip_all, fields(repo = %self.repo_details))]
    fn stopping(&mut self, ctx: &mut Self::Context) -> Running {
        info!("Checking webhook");
        match self.webhook_id.take() {
            Some(webhook_id) => {
                info!(%webhook_id, "Unregistring webhook");
                let forge = self.forge.clone();
                async move {
                    if let Err(err) = forge.unregister_webhook(&webhook_id).await {
                        warn!("unregistering webhook: {err}");
                    }
                }
                .in_current_span()
                .into_actor(self)
                .wait(ctx);
                Running::Continue
            }
            None => Running::Stop,
        }
    }
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct CloneRepo;
impl Handler<CloneRepo> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::CloneRepo", skip_all, fields(repo = %self.repo_details, gitdir = %self.repo_details.gitdir))]
    fn handle(&mut self, _msg: CloneRepo, ctx: &mut Self::Context) -> Self::Result {
        let gitdir = self.repo_details.gitdir.clone();
        match git::repository::open(&self.repository, &self.repo_details, gitdir) {
            Ok(repository) => {
                self.open_repository.replace(repository);
                if self.repo_details.repo_config.is_none() {
                    ctx.address().do_send(LoadConfigFromRepo);
                } else {
                    ctx.address().do_send(ValidateRepo {
                        message_token: self.message_token,
                    });
                }
            }
            Err(err) => warn!("Could not open repo: {err}"),
        }
    }
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct LoadConfigFromRepo;
impl Handler<LoadConfigFromRepo> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::LoadConfigFromRepo", skip_all, fields(repo = %self.repo_details))]
    fn handle(&mut self, _msg: LoadConfigFromRepo, ctx: &mut Self::Context) -> Self::Result {
        let details = self.repo_details.clone();
        let addr = ctx.address();
        let Some(open_repository) = self.open_repository.clone() else {
            warn!("missing open repository - can't load configuration");
            return;
        };
        repo_actor::load::load_file(details, addr, open_repository)
            .in_current_span()
            .into_actor(self)
            .wait(ctx);
    }
}

#[derive(Message)]
#[rtype(result = "()")]
struct LoadedConfig(git_next_config::RepoConfig);
impl Handler<LoadedConfig> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::LoadedConfig", skip_all, fields(repo = %self.repo_details, branches = %msg.0))]
    fn handle(&mut self, msg: LoadedConfig, ctx: &mut Self::Context) -> Self::Result {
        let repo_config = msg.0;
        self.repo_details.repo_config.replace(repo_config);

        ctx.address().do_send(ValidateRepo {
            message_token: self.message_token,
        });
    }
}

#[derive(derive_more::Constructor, Message)]
#[rtype(result = "()")]
pub struct ValidateRepo {
    message_token: MessageToken,
}
impl Handler<ValidateRepo> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::ValidateRepo", skip_all, fields(repo = %self.repo_details, token = %msg.message_token))]
    fn handle(&mut self, msg: ValidateRepo, ctx: &mut Self::Context) -> Self::Result {
        match msg.message_token {
            message_token if self.message_token < message_token => {
                info!(%message_token, "New message token");
                self.message_token = msg.message_token;
            }
            message_token if self.message_token > message_token => {
                info!("Dropping message from previous generation");
                return; // message is expired
            }
            _ => {
                // do nothing
            }
        }
        if self.webhook_id.is_none() {
            let forge_alias = self.repo_details.forge.forge_alias();
            let repo_alias = &self.repo_details.repo_alias;
            let webhook_url = self.webhook.url(forge_alias, repo_alias);
            let forge = self.forge.clone();
            let addr = ctx.address();
            async move {
                if let Err(err) =
                    forge
                        .register_webhook(&webhook_url)
                        .await
                        .and_then(|registered_webhook| {
                            addr.try_send(WebhookRegistered::from(registered_webhook))
                                .map_err(|e| {
                                    git::forge::webhook::Error::FailedToNotifySelf(e.to_string())
                                })
                        })
                {
                    warn!("registering webhook: {err}");
                }
            }
            .in_current_span()
            .into_actor(self)
            .wait(ctx);
        }
        if let (Some(repository), Some(repo_config)) = (
            self.open_repository.clone(),
            self.repo_details.repo_config.clone(),
        ) {
            let repo_details = self.repo_details.clone();
            let addr = ctx.address();
            let message_token = self.message_token;
            async move {
                match validate_positions(&repository, &repo_details, repo_config) {
                    Ok(Positions {
                        main,
                        next,
                        dev,
                        dev_commit_history,
                    }) => {
                        addr.do_send(StartMonitoring::new(main, next, dev, dev_commit_history));
                    }
                    Err(err) => {
                        warn!("{:?}", err);
                        tokio::time::sleep(Duration::from_secs(10)).await;
                        addr.do_send(ValidateRepo::new(message_token));
                    }
                }
            }
            .in_current_span()
            .into_actor(self)
            .wait(ctx);
        }
    }
}

#[derive(Debug, derive_more::Constructor, Message)]
#[rtype(result = "()")]
pub struct StartMonitoring {
    main: git::Commit,
    next: git::Commit,
    dev: git::Commit,
    dev_commit_history: Vec<git::Commit>,
}
impl Handler<StartMonitoring> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::StartMonitoring", skip_all, 
        fields(token = %self.message_token, repo = %self.repo_details, main = %msg.main, next= %msg.next, dev = %msg.dev))
    ]
    fn handle(&mut self, msg: StartMonitoring, ctx: &mut Self::Context) -> Self::Result {
        let Some(repo_config) = self.repo_details.repo_config.clone() else {
            warn!("No config loaded");
            return;
        };

        let next_ahead_of_main = msg.main != msg.next;
        let dev_ahead_of_next = msg.next != msg.dev;
        info!(next_ahead_of_main, dev_ahead_of_next, "StartMonitoring");

        let addr = ctx.address();
        let forge = self.forge.clone();

        if next_ahead_of_main {
            status::check_next(msg.next, addr, forge, self.message_token)
                .in_current_span()
                .into_actor(self)
                .wait(ctx);
        } else if dev_ahead_of_next {
            if let Some(repository) = self.open_repository.clone() {
                branch::advance_next(
                    msg.next,
                    msg.dev_commit_history,
                    self.repo_details.clone(),
                    repo_config,
                    repository,
                    addr,
                    self.message_token,
                )
                .in_current_span()
                .into_actor(self)
                .wait(ctx);
            }
        }
    }
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct WebhookRegistered(config::WebhookId, config::WebhookAuth);
impl From<RegisteredWebhook> for WebhookRegistered {
    fn from(value: RegisteredWebhook) -> Self {
        Self(value.id().clone(), value.auth().clone())
    }
}
impl Handler<WebhookRegistered> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::WebhookRegistered", skip_all, fields(repo = %self.repo_details, webhook_id = %msg.0))]
    fn handle(&mut self, msg: WebhookRegistered, _ctx: &mut Self::Context) -> Self::Result {
        self.webhook_id.replace(msg.0);
        self.webhook_auth.replace(msg.1);
    }
}

#[derive(Message)]
#[rtype(result = "()")]
pub struct AdvanceMainTo(git::Commit);
impl Handler<AdvanceMainTo> for RepoActor {
    type Result = ();
    #[tracing::instrument(name = "RepoActor::AdvanceMainTo", skip_all, fields(repo = %self.repo_details, commit = %msg.0))]
    fn handle(&mut self, msg: AdvanceMainTo, ctx: &mut Self::Context) -> Self::Result {
        let Some(repo_config) = self.repo_details.repo_config.clone() else {
            warn!("No config loaded");
            return;
        };
        let Some(repository) = self.open_repository.clone() else {
            warn!("No repository opened");
            return;
        };
        let repo_details = self.repo_details.clone();
        let addr = ctx.address();
        let message_token = self.message_token;
        async move {
            branch::advance_main(msg.0, &repo_details, &repo_config, &repository).await;
            match repo_config.source() {
                git_next_config::RepoConfigSource::Repo => addr.do_send(LoadConfigFromRepo),
                git_next_config::RepoConfigSource::Server => {
                    addr.do_send(ValidateRepo { message_token })
                }
            }
        }
        .in_current_span()
        .into_actor(self)
        .wait(ctx);
    }
}

#[derive(Copy, Clone, Default, Debug, PartialEq, Eq, PartialOrd, Ord, derive_more::Display)]
pub struct MessageToken(u32);
impl MessageToken {
    pub fn new() -> Self {
        Self::default()
    }
    pub const fn next(&self) -> Self {
        Self(self.0 + 1)
    }
}