/*
 * Copyright (C) 2022  Aravinth Manivannan <realaravinth@batsense.net>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
use actix_web::web;
use actix_web::HttpRequest;
use hmac::{Hmac, Mac};
use serde::{Deserialize, Serialize};
use sha2::Sha256;
use tracing::{info, warn};
use url::Url;

use crate::ctx::Ctx;
use crate::errors::ServiceError;
use crate::errors::ServiceResult;

pub type HmacSha256 = Hmac<Sha256>;

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct CommitPerson {
    pub name: String,
    pub email: String,
    pub username: String,
}

#[derive(Serialize, Deserialize, Default, Debug, Clone, Eq, PartialEq)]
pub struct Commit {
    pub id: String,
    pub message: String,
    pub url: String,
    pub author: CommitPerson,
    pub committer: CommitPerson,
    pub verification: serde_json::Value,
    pub timestamp: String,
    pub added: serde_json::Value,
    pub removed: serde_json::Value,
    pub modified: serde_json::Value,
}

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct Person {
    pub id: usize,
    pub login: String,
    pub full_name: String,
    pub email: String,
    pub avatar_url: String,
    pub language: String,
    pub is_admin: bool,
    pub last_login: String,
    pub created: String,
    pub restricted: bool,
    pub active: bool,
    pub prohibit_login: bool,
    pub location: String,
    pub website: String,
    pub description: String,
    pub visibility: String,
    pub followers_count: usize,
    pub following_count: usize,
    pub starred_repos_count: usize,
    pub username: String,
}

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct Permissions {
    pub admin: bool,
    pub push: bool,
    pub pull: bool,
}

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct InternalTracker {
    pub enable_time_tracker: bool,
    pub allow_only_contributors_to_track_time: bool,
    pub enable_issue_dependencies: bool,
}

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct Repository {
    pub id: usize,
    pub owner: Person,
    pub name: String,
    pub full_name: String,
    pub description: String,
    pub empty: bool,
    pub private: bool,
    pub fork: bool,
    pub template: bool,
    pub parent: Option<serde_json::Value>,
    pub mirror: bool,
    pub size: usize,
    pub html_url: String,
    pub ssh_url: String,
    pub clone_url: String,
    pub original_url: String,
    pub website: String,
    pub stars_count: usize,
    pub forks_count: usize,
    pub watchers_count: usize,
    pub open_issues_count: usize,
    pub open_pr_counter: usize,
    pub release_counter: usize,
    pub default_branch: String,
    pub archived: bool,
    pub created_at: String,
    pub updated_at: String,
    pub permissions: Permissions,
    pub has_issues: bool,
    pub internal_tracker: InternalTracker,
    pub has_wiki: bool,
    pub has_pull_requests: bool,
    pub has_projects: bool,
    pub ignore_whitespace_conflicts: bool,
    pub allow_merge_commits: bool,
    pub allow_rebase: bool,
    pub allow_rebase_explicit: bool,
    pub allow_squash_merge: bool,
    pub default_merge_style: String,
    pub avatar_url: String,
    pub internal: bool,
    pub mirror_interval: String,
    pub mirror_updated: String,
    pub repo_transfer: Option<serde_json::Value>,
}

#[derive(Serialize, Deserialize, Debug, Default, Clone, Eq, PartialEq)]
pub struct WebhookPayload {
    #[serde(rename(serialize = "ref", deserialize = "ref"))]
    pub reference: String,
    pub before: String,
    pub after: String,
    pub compare_url: String,
    pub repository: Repository,
    pub pusher: Person,
    pub sender: Person,
}

impl Ctx {
    pub async fn process_webhook(
        &self,
        body: &web::Bytes,
        req: &HttpRequest,
        auth_token: &str,
    ) -> ServiceResult<()> {
        let headers = req.headers();
        let _uuid = headers.get("X-Gitea-Delivery").unwrap();
        let sig = headers.get("X-Gitea-Signature").unwrap();
        let sig = hex::decode(sig).unwrap();
        let event_type = headers.get("X-Gitea-Event").unwrap();

        let payload: WebhookPayload = serde_json::from_slice(&body).unwrap();

        let hook = self.db.get_webhook(auth_token).await?;

        for url in [
            &payload.repository.html_url,
            &payload.repository.ssh_url,
            &payload.repository.clone_url,
        ] {
            if self.db.site_with_repository_exists(url).await? {
                let mut mac = HmacSha256::new_from_slice(hook.gitea_webhook_secret.as_bytes())?;
                mac.update(&body);
                mac.verify_slice(&sig[..])?;

                let site = self.db.get_site_from_repo_url(url).await?;
                self.db
                    .webhook_link_site(auth_token, &Url::parse(&site.repo_url)?)
                    .await?;
                if payload.reference.contains(&site.branch) {
                    info!(
                        "[webhook][forgejo/gitea] received update {:?} from {url} repository on deployed branch",
                        event_type
                    );
                    self.update_site(&site.site_secret, Some(site.branch))
                        .await?;
                } else {
                    info!(
                        "[webhook][forgejo/gitea] received update {:?} from {url} repository on non-deployed branch {}",
                        event_type,
                        payload.reference
                    );
                }
                return Ok(());
            }
        }
        warn!(
            "[webhook][forgejo/gitea] stray update from {} repository",
            payload.repository.html_url
        );
        Err(ServiceError::WebsiteNotFound)
    }
}