/*
 * Copyright (C) 2023  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 url::Url;
use uuid::Uuid;

use crate::api::v1::get_random;
use crate::db::{
    JobState, JOB_STATES, JOB_STATE_CREATE, JOB_STATE_FINISH, JOB_STATE_RUNNING,
};
use crate::errors::*;
use crate::mcaptcha::PerformanceAnalytics;
use crate::Data;

use sqlx::types::time::OffsetDateTime;

fn now_unix_time_stamp() -> OffsetDateTime {
    OffsetDateTime::now_utc()
}

impl Data {
    /// Check if an mCaptcha instance is registered on the database
    pub async fn mcaptcha_url_exists(&self, url: &str) -> ServiceResult<bool> {
        let res = sqlx::query!(
            "SELECT EXISTS (SELECT 1 from survey_mcaptcha_hostname WHERE url = $1)",
            url
        )
        .fetch_one(&self.db)
        .await?;

        let mut resp = false;
        if let Some(x) = res.exists {
            if x {
                resp = true;
            }
        }

        Ok(resp)
    }

    /// Register an mCaptcha instance
    pub async fn mcaptcha_register_instance(&self, url: &str) -> ServiceResult<String> {
        let secret = get_random(32);
        sqlx::query!(
            "INSERT INTO survey_mcaptcha_hostname (url, secret) VALUES ($1, $2)",
            url,
            &secret,
        )
        .execute(&self.db)
        .await?;
        Ok(secret)
    }

    /// Update the secret of an mCaptcha instance
    pub async fn mcaptcha_update_secret(&self, url: &str) -> ServiceResult<String> {
        let secret = get_random(32);
        sqlx::query!(
            "UPDATE survey_mcaptcha_hostname set secret = $1 WHERE url = $2",
            &secret,
            url
        )
        .execute(&self.db)
        .await?;
        Ok(secret)
    }

    /// Authenticate an mCaptcha instance and return its URL
    pub async fn mcaptcha_authenticate(&self, secret: &str) -> ServiceResult<()> {
        let res = sqlx::query!(
            "SELECT EXISTS (
        SELECT
            url
        FROM
            survey_mcaptcha_hostname
        WHERE secret = $1
        )",
            secret
        )
        .fetch_one(&self.db)
        .await?;

        if !matches!(res.exists, Some(true)) {
            return Err(ServiceError::WrongPassword);
        }

        Ok(())
    }

    /// Delete mCaptcha instance from database
    pub async fn mcaptcha_delete_mcaptcha_instance(
        &self,
        url: &str,
        secret: &str,
    ) -> ServiceResult<()> {
        sqlx::query!(
            "DELETE FROM survey_mcaptcha_hostname WHERE secret = $1 AND url =$2",
            secret,
            url
        )
        .execute(&self.db)
        .await?;
        Ok(())
    }
    /// Delete mCaptcha campaign from database
    pub async fn mcaptcha_delete_mcaptcha_campaign(
        &self,
        campaign_id: &Uuid,
        secret: &str,
    ) -> ServiceResult<()> {
        let campaign_str = campaign_id.to_string();
        sqlx::query!(
            "DELETE FROM
                survey_mcaptcha_campaign
            WHERE
                campaign_id = $1
            AND
                url_id = (
                    SELECT
                        ID
                    FROM
                        survey_mcaptcha_hostname
                    WHERE
                        secret = $2
                    )",
            &campaign_str,
            secret
        )
        .execute(&self.db)
        .await?;

        Ok(())
    }

    /// Check if an mCaptcha instance campaign is registered on DB
    pub async fn mcaptcha_campaign_is_registered(
        &self,
        campaign_id: &Uuid,
        secret: &str,
    ) -> ServiceResult<bool> {
        let campaign_str = campaign_id.to_string();

        let res = sqlx::query!(
            "SELECT EXISTS (
        SELECT
            ID
        FROM
            survey_mcaptcha_campaign
        WHERE
            campaign_id = $1
        AND
            url_id = (
                SELECT
                    ID
                FROM
                    survey_mcaptcha_hostname
                WHERE
                    secret = $2
                )
        )",
            &campaign_str,
            secret
        )
        .fetch_one(&self.db)
        .await?;

        let mut resp = false;
        if let Some(x) = res.exists {
            if x {
                resp = true;
            }
        }
        Ok(resp)
    }

    /// Register an mCaptcha instance campaign on DB
    pub async fn mcaptcha_register_campaign(
        &self,
        campaign_id: &Uuid,
        secret: &str,
    ) -> ServiceResult<()> {
        let campaign_str = campaign_id.to_string();
        let public_id = Uuid::new_v4();

        sqlx::query!(
            "INSERT INTO
                survey_mcaptcha_campaign (campaign_id, public_id, url_id)
            VALUES ($1, $2, (SELECT ID FROM survey_mcaptcha_hostname WHERE secret = $3));",
            &campaign_str,
            &public_id.to_string(),
            secret,
        )
        .execute(&self.db)
        .await?;
        Ok(())
    }

    /// Register an mCaptcha instance campaign on DB
    pub async fn mcaptcha_get_campaign_public_id(
        &self,
        campaign_id: &Uuid,
        secret: &str,
    ) -> ServiceResult<Uuid> {
        let campaign_str = campaign_id.to_string();
        struct S {
            public_id: String,
        }

        let res = sqlx::query_as!(
            S,
            "SELECT
                public_id
            FROM
                survey_mcaptcha_campaign
            WHERE
                campaign_id = $1
            AND
                url_id = (SELECT ID FROM survey_mcaptcha_hostname WHERE secret = $2);",
            &campaign_str,
            secret,
        )
        .fetch_one(&self.db)
        .await?;

        Ok(Uuid::parse_str(&res.public_id).unwrap())
    }

    /// Get an mCaptcha instance campaign checkpoint
    pub async fn mcaptcha_get_checkpoint(
        &self,
        campaign_id: &Uuid,
    ) -> ServiceResult<usize> {
        let campaign_str = campaign_id.to_string();

        struct CheckPoint {
            synced_till: i32,
        }

        let checkpoint = sqlx::query_as!(
            CheckPoint,
            "SELECT
            synced_till
        FROM
            survey_mcaptcha_campaign
        WHERE 
            campaign_id = $1;",
            &campaign_str,
        )
        .fetch_one(&self.db)
        .await?;
        let checkpoint = checkpoint.synced_till as usize;
        Ok(checkpoint)
    }

    /// Set an mCaptcha instance campaign checkpoint
    pub async fn mcaptcha_set_checkpoint(
        &self,
        campaign_id: &Uuid,
        checkpoint: usize,
    ) -> ServiceResult<()> {
        let campaign_str = campaign_id.to_string();
        sqlx::query!(
            "UPDATE
                survey_mcaptcha_campaign
            SET
                synced_till = $1
            WHERE 
                campaign_id = $2; ",
            checkpoint as i32,
            &campaign_str,
        )
        .execute(&self.db)
        .await?;

        Ok(())
    }

    /// Store mCaptcha instance campaign analytics
    pub async fn mcaptcha_insert_analytics(
        &self,
        campaign_id: &Uuid,
        r: &PerformanceAnalytics,
    ) -> ServiceResult<()> {
        let campaign_str = campaign_id.to_string();
        sqlx::query!(
            "INSERT INTO
                survey_mcaptcha_analytics (
                    campaign_id, time, difficulty_factor, worker_type
                )
                VALUES ((
                    SELECT
                        ID
                    FROM
                        survey_mcaptcha_campaign
                    WHERE 
                        campaign_id = $1
                    ), $2,  $3, $4
                );",
            &campaign_str,
            r.time as i32,
            r.difficulty_factor as i32,
            &r.worker_type,
        )
        .execute(&self.db)
        .await?;
        Ok(())
    }

    /// fetch PoW analytics
    pub async fn mcaptcha_analytics_fetch(
        &self,
        public_id: &Uuid,
        limit: usize,
        offset: usize,
    ) -> ServiceResult<Vec<PerformanceAnalytics>> {
        let public_id_str = public_id.to_string();
        struct P {
            id: i32,
            time: i32,
            difficulty_factor: i32,
            worker_type: String,
        }

        impl From<P> for PerformanceAnalytics {
            fn from(v: P) -> Self {
                Self {
                    time: v.time as u32,
                    difficulty_factor: v.difficulty_factor as u32,
                    worker_type: v.worker_type,
                    id: v.id as usize,
                }
            }
        }

        let mut c = sqlx::query_as!(
            P,
            "SELECT id, time, difficulty_factor, worker_type FROM survey_mcaptcha_analytics
            WHERE 
                campaign_id = (
                    SELECT 
                        ID FROM survey_mcaptcha_campaign 
                    WHERE 
                        public_id = $1
                )
                ORDER BY ID
                OFFSET $2 LIMIT $3
                ",
            &public_id_str,
            offset as i32,
            limit as i32
        )
        .fetch_all(&self.db)
        .await?;
        let mut res = Vec::with_capacity(c.len());
        for i in c.drain(0..) {
            res.push(i.into())
        }

        Ok(res)
    }

    pub async fn get_next_job_to_run(&self) -> ServiceResult<Option<SchedulerJob>> {
        let res = match sqlx::query_as!(
            InnerSchedulerJob,
            "SELECT
                 survey_mcaptcha_campaign.campaign_id,
                 survey_mcaptcha_upload_jobs.public_id,
                 survey_mcaptcha_hostname.url
              FROM
                 survey_mcaptcha_campaign
              INNER JOIN
                  survey_mcaptcha_upload_jobs
              ON
                  survey_mcaptcha_upload_jobs.campaign_id = survey_mcaptcha_campaign.ID
              INNER JOIN
                  survey_mcaptcha_hostname
              ON
                  survey_mcaptcha_hostname.ID = survey_mcaptcha_campaign.url_id
              WHERE
                     survey_mcaptcha_upload_jobs.job_state = (
                         SELECT ID FROM survey_mcaptcha_upload_job_states WHERE name = $1
                     )
             AND
                 survey_mcaptcha_upload_jobs.finished_at is NULL
             AND
                 survey_mcaptcha_upload_jobs.scheduled_at is NULL
             ORDER BY created_at ASC;",
            &JOB_STATE_CREATE.name
        )
        .fetch_one(&self.db)
        .await
        {
            Ok(res) => Ok(Some(res.into())),
            Err(sqlx::Error::RowNotFound) => Ok(None),
            Err(e) => Err(e),
        }?;
        Ok(res)
    }

    pub async fn add_job(&self, campaign_id: &Uuid) -> ServiceResult<Uuid> {
        let now = now_unix_time_stamp();

        if let Some(unfinished_job) =
            self.get_unfinished_job_for_campaign(campaign_id).await?
        {
            return Ok(unfinished_job.public_job_id);
        }

        let public_id = Uuid::new_v4();
        let public_id_str = public_id.to_string();

        let campaign_str = campaign_id.to_string();
        sqlx::query!(
          "INSERT INTO survey_mcaptcha_upload_jobs
               (campaign_id, job_state, created_at, public_id)
                   VALUES (
                       (SELECT ID FROM survey_mcaptcha_campaign WHERE campaign_id = $1),
                       (SELECT ID FROM survey_mcaptcha_upload_job_states WHERE name = $2),
                       $3, $4)",
          &campaign_str,
          &JOB_STATE_CREATE.name,
          now,
          public_id_str
      )
      .execute(&self.db)
      .await?;
        Ok(public_id)
    }

    pub async fn get_unfinished_job_for_campaign(
        &self,
        campaign_id: &Uuid,
    ) -> ServiceResult<Option<Job>> {
        let res = match sqlx::query_as!(
          InnerJob,
          "
          SELECT
              survey_mcaptcha_upload_jobs.ID,
              survey_mcaptcha_upload_jobs.public_id,
              survey_mcaptcha_campaign.campaign_id,
              survey_mcaptcha_campaign.public_id as campaign_public_id,
              survey_mcaptcha_upload_job_states.name,
              survey_mcaptcha_upload_jobs.created_at,
              survey_mcaptcha_upload_jobs.scheduled_at,
              survey_mcaptcha_upload_jobs.finished_at

          FROM survey_mcaptcha_upload_jobs
          INNER JOIN
              survey_mcaptcha_upload_job_states
          ON
              survey_mcaptcha_upload_job_states.ID = survey_mcaptcha_upload_jobs.job_state
          INNER JOIN
              survey_mcaptcha_campaign
          ON
             survey_mcaptcha_campaign.ID = survey_mcaptcha_upload_jobs.campaign_id
          WHERE
              survey_mcaptcha_campaign.campaign_id = $1
          AND
              survey_mcaptcha_upload_job_states.name = $2;",
          &campaign_id.to_string(),
          &JOB_STATE_CREATE.name
      )
      .fetch_one(&self.db)
      .await {
      Ok(res) => Ok(Some(res.into())),
      Err(sqlx::Error::RowNotFound) => Ok(None),
      Err(e) => Err(e),
      }?;
        Ok(res)
    }

    pub async fn get_job(&self, public_id: &uuid::Uuid) -> ServiceResult<Option<Job>> {
        let res = match sqlx::query_as!(
          InnerJob,
          "
          SELECT
              survey_mcaptcha_upload_jobs.ID,
              survey_mcaptcha_upload_jobs.public_id,
              survey_mcaptcha_campaign.campaign_id,
              survey_mcaptcha_campaign.public_id as campaign_public_id,
              survey_mcaptcha_upload_job_states.name,
              survey_mcaptcha_upload_jobs.created_at,
              survey_mcaptcha_upload_jobs.scheduled_at,
              survey_mcaptcha_upload_jobs.finished_at

          FROM survey_mcaptcha_upload_jobs
          INNER JOIN
              survey_mcaptcha_upload_job_states
          ON
              survey_mcaptcha_upload_job_states.ID = survey_mcaptcha_upload_jobs.job_state
          INNER JOIN
              survey_mcaptcha_campaign
          ON
             survey_mcaptcha_campaign.ID = survey_mcaptcha_upload_jobs.campaign_id
          WHERE
          survey_mcaptcha_upload_jobs.public_id = $1",
          &public_id.to_string()
      )
      .fetch_one(&self.db)
        .await {
      Ok(res) => Ok(Some(res.into())),
      Err(sqlx::Error::RowNotFound) => Ok(None),
      Err(e) => Err(e),
      }?;

        Ok(res)
    }

    pub async fn get_all_jobs_of_state(
        &self,
        state: &JobState,
    ) -> ServiceResult<Vec<Job>> {
        let mut res = sqlx::query_as!(
          InnerJob,
          "
          SELECT
              survey_mcaptcha_upload_jobs.ID,
              survey_mcaptcha_upload_jobs.public_id,
              survey_mcaptcha_campaign.campaign_id,
              survey_mcaptcha_campaign.public_id as campaign_public_id,
              survey_mcaptcha_upload_job_states.name,
              survey_mcaptcha_upload_jobs.created_at,
              survey_mcaptcha_upload_jobs.scheduled_at,
              survey_mcaptcha_upload_jobs.finished_at

          FROM survey_mcaptcha_upload_jobs
          INNER JOIN
              survey_mcaptcha_upload_job_states
          ON
              survey_mcaptcha_upload_job_states.ID = survey_mcaptcha_upload_jobs.job_state
          INNER JOIN
              survey_mcaptcha_campaign
          ON
             survey_mcaptcha_campaign.ID = survey_mcaptcha_upload_jobs.campaign_id
          WHERE
              survey_mcaptcha_upload_job_states.name = $1;",
          &state.name
      )
      .fetch_all(&self.db)
      .await?;

        let res = res.drain(0..).map(|r| r.into()).collect();

        Ok(res)
    }

    pub async fn mark_job_scheduled(&self, job: &SchedulerJob) -> ServiceResult<()> {
        let now = now_unix_time_stamp();
        sqlx::query!(
          "
          UPDATE
              survey_mcaptcha_upload_jobs
          SET
              job_state = (SELECT ID FROM survey_mcaptcha_upload_job_states WHERE name = $1),
              scheduled_at = $2
          WHERE public_id = $3;",
          &JOB_STATE_RUNNING.name,
          now,
          &job.public_job_id.to_string(),
      )
      .execute(&self.db)
      .await
      ?;

        Ok(())
    }

    pub async fn mark_job_finished(&self, job: &SchedulerJob) -> ServiceResult<()> {
        let now = now_unix_time_stamp();
        sqlx::query!(
          "
          UPDATE
              survey_mcaptcha_upload_jobs
          SET
              job_state = (SELECT ID FROM survey_mcaptcha_upload_job_states WHERE name = $1),
              finished_at = $2
          WHERE public_id = $3;",
          &JOB_STATE_FINISH.name,
          now,
          &job.public_job_id.to_string(),
      )
      .execute(&self.db)
      .await
      ?;

        Ok(())
    }
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct SchedulerJob {
    pub campaign_id: Uuid,
    pub public_job_id: Uuid,
    pub url: Url,
}

#[derive(Clone, Debug, PartialEq, Eq)]
struct InnerSchedulerJob {
    campaign_id: String,
    public_id: String,
    url: String,
}
impl From<InnerSchedulerJob> for SchedulerJob {
    fn from(j: InnerSchedulerJob) -> Self {
        SchedulerJob {
            campaign_id: Uuid::parse_str(&j.campaign_id).unwrap(),
            public_job_id: Uuid::parse_str(&j.public_id).unwrap(),
            url: Url::parse(&j.url).unwrap(),
        }
    }
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Job {
    pub state: JobState,
    pub campaign_id: Uuid,
    pub campaign_public_id: Uuid,
    pub public_job_id: Uuid,
    pub id: u32,
    pub created_at: OffsetDateTime,
    pub scheduled_at: Option<OffsetDateTime>,
    pub finished_at: Option<OffsetDateTime>,
}

struct InnerJob {
    name: String,
    campaign_id: String,
    public_id: String,
    campaign_public_id: String,
    id: i32,
    created_at: OffsetDateTime,
    scheduled_at: Option<OffsetDateTime>,
    finished_at: Option<OffsetDateTime>,
}

impl From<InnerJob> for Job {
    fn from(j: InnerJob) -> Self {
        Job {
            state: (JOB_STATES)
                .iter()
                .find(|d| d.name == j.name)
                .unwrap()
                .to_owned()
                .to_owned(),
            id: j.id as u32,
            created_at: j.created_at,
            scheduled_at: j.scheduled_at,
            finished_at: j.finished_at,

            campaign_id: Uuid::parse_str(&j.campaign_id).unwrap(),
            campaign_public_id: Uuid::parse_str(&j.campaign_public_id).unwrap(),
            public_job_id: Uuid::parse_str(&j.public_id).unwrap(),
        }
    }
}

#[cfg(test)]
mod tests {
    use crate::{mcaptcha::PerformanceAnalytics, tests::*};

    use super::*;
    use url::Url;

    #[actix_rt::test]
    async fn test_db_mcaptcha_works() {
        let url = Url::parse("http://test_add_campaign.example").unwrap();
        let data = get_test_data().await;
        let url_str = url.to_string();
        if data.mcaptcha_url_exists(&url_str).await.unwrap() {
            let secret = data.mcaptcha_update_secret(&url_str).await.unwrap();
            data.mcaptcha_delete_mcaptcha_instance(&url_str, &secret)
                .await
                .unwrap();
        }
        assert!(!data.mcaptcha_url_exists(&url_str).await.unwrap());

        let secret = data.mcaptcha_register_instance(&url_str).await.unwrap();
        assert!(data.mcaptcha_url_exists(&url_str).await.unwrap());
        let secret2 = data.mcaptcha_update_secret(&url_str).await.unwrap();
        assert_ne!(secret2, secret);
        let secret = secret2;

        assert!(data.mcaptcha_authenticate(&secret).await.is_ok());
        assert_eq!(
            data.mcaptcha_authenticate("foo").await.err(),
            Some(ServiceError::WrongPassword)
        );

        let uuid = Uuid::new_v4();

        if data
            .mcaptcha_campaign_is_registered(&uuid, &secret)
            .await
            .unwrap()
        {
            data.mcaptcha_delete_mcaptcha_campaign(&uuid, &secret)
                .await
                .unwrap();
        }

        assert!(!data
            .mcaptcha_campaign_is_registered(&uuid, &secret)
            .await
            .unwrap());
        data.mcaptcha_register_campaign(&uuid, &secret)
            .await
            .unwrap();
        assert!(data
            .mcaptcha_campaign_is_registered(&uuid, &secret)
            .await
            .unwrap());

        assert_eq!(data.mcaptcha_get_checkpoint(&uuid).await.unwrap(), 0);
        data.mcaptcha_set_checkpoint(&uuid, 1).await.unwrap();
        assert_eq!(data.mcaptcha_get_checkpoint(&uuid).await.unwrap(), 1);

        let analytics = PerformanceAnalytics {
            id: 1,
            time: 1,
            difficulty_factor: 1,
            worker_type: "foo".to_string(),
        };
        data.mcaptcha_insert_analytics(&uuid, &analytics)
            .await
            .unwrap();

        let public_id = data
            .mcaptcha_get_campaign_public_id(&uuid, &secret)
            .await
            .unwrap();
        let db_analytics = data
            .mcaptcha_analytics_fetch(&public_id, 50, 0)
            .await
            .unwrap();

        assert_eq!(db_analytics.len(), 1);
        assert_eq!(db_analytics[0].time, analytics.time);
        assert_eq!(
            db_analytics[0].difficulty_factor,
            analytics.difficulty_factor
        );
        assert_eq!(db_analytics[0].worker_type, analytics.worker_type);

        assert_eq!(
            data.mcaptcha_analytics_fetch(&public_id, 50, 1)
                .await
                .unwrap(),
            vec![]
        );

        // job related stuff

        let job1_public_id = data.add_job(&uuid).await.unwrap();
        let job = data.get_job(&job1_public_id).await.unwrap().unwrap();
        assert_eq!(public_id, job.campaign_public_id);
        assert_eq!(
            data.get_unfinished_job_for_campaign(&uuid)
                .await
                .unwrap()
                .unwrap(),
            job
        );
        let job2_public_id = data.add_job(&uuid).await.unwrap();
        let job2 = data.get_job(&job2_public_id).await.unwrap().unwrap();
        assert_eq!(job2, job);
        let scheduler_job = data.get_next_job_to_run().await.unwrap().unwrap();
        assert_eq!(scheduler_job.url, url);

        assert_eq!(
            data.get_next_job_to_run()
                .await
                .unwrap()
                .unwrap()
                .public_job_id,
            job.public_job_id
        );

        assert!(job.created_at < now_unix_time_stamp());
        assert!(job.scheduled_at.is_none());
        assert!(job.finished_at.is_none());
        assert_eq!(
            data.get_all_jobs_of_state(&JOB_STATE_CREATE).await.unwrap(),
            vec![job.clone()]
        );

        data.mark_job_scheduled(&scheduler_job).await.unwrap();
        assert!(data.get_next_job_to_run().await.unwrap().is_none(),);
        let job = data.get_job(&job.public_job_id).await.unwrap().unwrap();
        assert!(job.scheduled_at.is_some());
        assert_eq!(
            data.get_all_jobs_of_state(&JOB_STATE_RUNNING)
                .await
                .unwrap(),
            vec![job.clone()]
        );

        data.mark_job_finished(&scheduler_job).await.unwrap();
        let job = data.get_job(&job.public_job_id).await.unwrap().unwrap();
        assert!(job.finished_at.is_some());
        assert_eq!(
            data.get_all_jobs_of_state(&JOB_STATE_FINISH).await.unwrap(),
            vec![job.clone()]
        );

        let job2_public_id = data.add_job(&uuid).await.unwrap();
        let job2 = data.get_job(&job2_public_id).await.unwrap().unwrap();
        assert_ne!(job2.public_job_id, job.public_job_id);
        assert_eq!(
            data.get_next_job_to_run()
                .await
                .unwrap()
                .unwrap()
                .public_job_id,
            job2.public_job_id
        );
        assert_eq!(public_id, job2.campaign_public_id);
    }
}