lemmy/server/src/api/comment.rs

use super::*;
use crate::send_email;
use crate::settings::Settings;
use diesel::PgConnection;

#[derive(Serialize, Deserialize)]
pub struct CreateComment {
  content: String,
  parent_id: Option<i32>,
  edit_id: Option<i32>, // TODO this isn't used
  pub post_id: i32,
  auth: String,
}

#[derive(Serialize, Deserialize)]
pub struct EditComment {
  content: String,
  parent_id: Option<i32>, // TODO why are the parent_id, creator_id, post_id, etc fields required? They aren't going to change
  edit_id: i32,
  creator_id: i32,
  pub post_id: i32,
  removed: Option<bool>,
  deleted: Option<bool>,
  reason: Option<String>,
  read: Option<bool>,
  auth: String,
}

#[derive(Serialize, Deserialize)]
pub struct SaveComment {
  comment_id: i32,
  save: bool,
  auth: String,
}

#[derive(Serialize, Deserialize, Clone)]
pub struct CommentResponse {
  pub comment: CommentView,
  pub recipient_ids: Vec<i32>,
}

#[derive(Serialize, Deserialize)]
pub struct CreateCommentLike {
  comment_id: i32,
  pub post_id: i32,
  score: i16,
  auth: String,
}

impl Perform<CommentResponse> for Oper<CreateComment> {
  fn perform(&self, conn: &PgConnection) -> Result<CommentResponse, Error> {
    let data: &CreateComment = &self.data;

    let claims = match Claims::decode(&data.auth) {
      Ok(claims) => claims.claims,
      Err(_e) => return Err(APIError::err("not_logged_in").into()),
    };

    let user_id = claims.id;

    let hostname = &format!("https://{}", Settings::get().hostname);

    // Check for a community ban
    let post = Post::read(&conn, data.post_id)?;
    if CommunityUserBanView::get(&conn, user_id, post.community_id).is_ok() {
      return Err(APIError::err("community_ban").into());
    }

    // Check for a site ban
    if UserView::read(&conn, user_id)?.banned {
      return Err(APIError::err("site_ban").into());
    }

    let content_slurs_removed = remove_slurs(&data.content.to_owned());

    let comment_form = CommentForm {
      content: content_slurs_removed,
      parent_id: data.parent_id.to_owned(),
      post_id: data.post_id,
      creator_id: user_id,
      removed: None,
      deleted: None,
      read: None,
      updated: None,
    };

    let inserted_comment = match Comment::create(&conn, &comment_form) {
      Ok(comment) => comment,
      Err(_e) => return Err(APIError::err("couldnt_create_comment").into()),
    };

    let mut recipient_ids = Vec::new();

    // Scan the comment for user mentions, add those rows
    let extracted_usernames = extract_usernames(&comment_form.content);

    for username_mention in &extracted_usernames {
      if let Ok(mention_user) = User_::read_from_name(&conn, (*username_mention).to_string()) {
        // You can't mention yourself
        // At some point, make it so you can't tag the parent creator either
        // This can cause two notifications, one for reply and the other for mention
        if mention_user.id != user_id {
          recipient_ids.push(mention_user.id);

          let user_mention_form = UserMentionForm {
            recipient_id: mention_user.id,
            comment_id: inserted_comment.id,
            read: None,
          };

          // Allow this to fail softly, since comment edits might re-update or replace it
          // Let the uniqueness handle this fail
          match UserMention::create(&conn, &user_mention_form) {
            Ok(_mention) => (),
            Err(_e) => eprintln!("{}", &_e),
          };

          // Send an email to those users that have notifications on
          if mention_user.send_notifications_to_email {
            if let Some(mention_email) = mention_user.email {
              let subject = &format!(
                "{} - Mentioned by {}",
                Settings::get().hostname,
                claims.username
              );
              let html = &format!(
                "<h1>User Mention</h1><br><div>{} - {}</div><br><a href={}/inbox>inbox</a>",
                claims.username, comment_form.content, hostname
              );
              match send_email(subject, &mention_email, &mention_user.name, html) {
                Ok(_o) => _o,
                Err(e) => eprintln!("{}", e),
              };
            }
          }
        }
      }
    }

    // Send notifs to the parent commenter / poster
    match data.parent_id {
      Some(parent_id) => {
        let parent_comment = Comment::read(&conn, parent_id)?;
        if parent_comment.creator_id != user_id {
          let parent_user = User_::read(&conn, parent_comment.creator_id)?;
          recipient_ids.push(parent_user.id);

          if parent_user.send_notifications_to_email {
            if let Some(comment_reply_email) = parent_user.email {
              let subject = &format!(
                "{} - Reply from {}",
                Settings::get().hostname,
                claims.username
              );
              let html = &format!(
                "<h1>Comment Reply</h1><br><div>{} - {}</div><br><a href={}/inbox>inbox</a>",
                claims.username, comment_form.content, hostname
              );
              match send_email(subject, &comment_reply_email, &parent_user.name, html) {
                Ok(_o) => _o,
                Err(e) => eprintln!("{}", e),
              };
            }
          }
        }
      }
      // Its a post
      None => {
        if post.creator_id != user_id {
          let parent_user = User_::read(&conn, post.creator_id)?;
          recipient_ids.push(parent_user.id);

          if parent_user.send_notifications_to_email {
            if let Some(post_reply_email) = parent_user.email {
              let subject = &format!(
                "{} - Reply from {}",
                Settings::get().hostname,
                claims.username
              );
              let html = &format!(
                "<h1>Post Reply</h1><br><div>{} - {}</div><br><a href={}/inbox>inbox</a>",
                claims.username, comment_form.content, hostname
              );
              match send_email(subject, &post_reply_email, &parent_user.name, html) {
                Ok(_o) => _o,
                Err(e) => eprintln!("{}", e),
              };
            }
          }
        }
      }
    };

    // You like your own comment by default
    let like_form = CommentLikeForm {
      comment_id: inserted_comment.id,
      post_id: data.post_id,
      user_id,
      score: 1,
    };

    let _inserted_like = match CommentLike::like(&conn, &like_form) {
      Ok(like) => like,
      Err(_e) => return Err(APIError::err("couldnt_like_comment").into()),
    };

    let comment_view = CommentView::read(&conn, inserted_comment.id, Some(user_id))?;

    Ok(CommentResponse {
      comment: comment_view,
      recipient_ids,
    })
  }
}

impl Perform<CommentResponse> for Oper<EditComment> {
  fn perform(&self, conn: &PgConnection) -> Result<CommentResponse, Error> {
    let data: &EditComment = &self.data;

    let claims = match Claims::decode(&data.auth) {
      Ok(claims) => claims.claims,
      Err(_e) => return Err(APIError::err("not_logged_in").into()),
    };

    let user_id = claims.id;

    let orig_comment = CommentView::read(&conn, data.edit_id, None)?;

    // You are allowed to mark the comment as read even if you're banned.
    if data.read.is_none() {
      // Verify its the creator or a mod, or an admin
      let mut editors: Vec<i32> = vec![data.creator_id];
      editors.append(
        &mut CommunityModeratorView::for_community(&conn, orig_comment.community_id)?
          .into_iter()
          .map(|m| m.user_id)
          .collect(),
      );
      editors.append(&mut UserView::admins(&conn)?.into_iter().map(|a| a.id).collect());

      if !editors.contains(&user_id) {
        return Err(APIError::err("no_comment_edit_allowed").into());
      }

      // Check for a community ban
      if CommunityUserBanView::get(&conn, user_id, orig_comment.community_id).is_ok() {
        return Err(APIError::err("community_ban").into());
      }

      // Check for a site ban
      if UserView::read(&conn, user_id)?.banned {
        return Err(APIError::err("site_ban").into());
      }
    }

    let content_slurs_removed = remove_slurs(&data.content.to_owned());

    let comment_form = CommentForm {
      content: content_slurs_removed,
      parent_id: data.parent_id,
      post_id: data.post_id,
      creator_id: data.creator_id,
      removed: data.removed.to_owned(),
      deleted: data.deleted.to_owned(),
      read: data.read.to_owned(),
      updated: if data.read.is_some() {
        orig_comment.updated
      } else {
        Some(naive_now())
      },
    };

    let _updated_comment = match Comment::update(&conn, data.edit_id, &comment_form) {
      Ok(comment) => comment,
      Err(_e) => return Err(APIError::err("couldnt_update_comment").into()),
    };

    let mut recipient_ids = Vec::new();

    // Scan the comment for user mentions, add those rows
    let extracted_usernames = extract_usernames(&comment_form.content);

    for username_mention in &extracted_usernames {
      let mention_user = User_::read_from_name(&conn, (*username_mention).to_string());

      if mention_user.is_ok() {
        let mention_user_id = mention_user?.id;

        // You can't mention yourself
        // At some point, make it so you can't tag the parent creator either
        // This can cause two notifications, one for reply and the other for mention
        if mention_user_id != user_id {
          recipient_ids.push(mention_user_id);

          let user_mention_form = UserMentionForm {
            recipient_id: mention_user_id,
            comment_id: data.edit_id,
            read: None,
          };

          // Allow this to fail softly, since comment edits might re-update or replace it
          // Let the uniqueness handle this fail
          match UserMention::create(&conn, &user_mention_form) {
            Ok(_mention) => (),
            Err(_e) => eprintln!("{}", &_e),
          }
        }
      }
    }

    // Add to recipient ids
    match data.parent_id {
      Some(parent_id) => {
        let parent_comment = Comment::read(&conn, parent_id)?;
        if parent_comment.creator_id != user_id {
          let parent_user = User_::read(&conn, parent_comment.creator_id)?;
          recipient_ids.push(parent_user.id);
        }
      }
      None => {
        let post = Post::read(&conn, data.post_id)?;
        recipient_ids.push(post.creator_id);
      }
    }

    // Mod tables
    if let Some(removed) = data.removed.to_owned() {
      let form = ModRemoveCommentForm {
        mod_user_id: user_id,
        comment_id: data.edit_id,
        removed: Some(removed),
        reason: data.reason.to_owned(),
      };
      ModRemoveComment::create(&conn, &form)?;
    }

    let comment_view = CommentView::read(&conn, data.edit_id, Some(user_id))?;

    Ok(CommentResponse {
      comment: comment_view,
      recipient_ids,
    })
  }
}

impl Perform<CommentResponse> for Oper<SaveComment> {
  fn perform(&self, conn: &PgConnection) -> Result<CommentResponse, Error> {
    let data: &SaveComment = &self.data;

    let claims = match Claims::decode(&data.auth) {
      Ok(claims) => claims.claims,
      Err(_e) => return Err(APIError::err("not_logged_in").into()),
    };

    let user_id = claims.id;

    let comment_saved_form = CommentSavedForm {
      comment_id: data.comment_id,
      user_id,
    };

    if data.save {
      match CommentSaved::save(&conn, &comment_saved_form) {
        Ok(comment) => comment,
        Err(_e) => return Err(APIError::err("couldnt_save_comment").into()),
      };
    } else {
      match CommentSaved::unsave(&conn, &comment_saved_form) {
        Ok(comment) => comment,
        Err(_e) => return Err(APIError::err("couldnt_save_comment").into()),
      };
    }

    let comment_view = CommentView::read(&conn, data.comment_id, Some(user_id))?;

    Ok(CommentResponse {
      comment: comment_view,
      recipient_ids: Vec::new(),
    })
  }
}

impl Perform<CommentResponse> for Oper<CreateCommentLike> {
  fn perform(&self, conn: &PgConnection) -> Result<CommentResponse, Error> {
    let data: &CreateCommentLike = &self.data;

    let claims = match Claims::decode(&data.auth) {
      Ok(claims) => claims.claims,
      Err(_e) => return Err(APIError::err("not_logged_in").into()),
    };

    let user_id = claims.id;

    let mut recipient_ids = Vec::new();

    // Don't do a downvote if site has downvotes disabled
    if data.score == -1 {
      let site = SiteView::read(&conn)?;
      if !site.enable_downvotes {
        return Err(APIError::err("downvotes_disabled").into());
      }
    }

    // Check for a community ban
    let post = Post::read(&conn, data.post_id)?;
    if CommunityUserBanView::get(&conn, user_id, post.community_id).is_ok() {
      return Err(APIError::err("community_ban").into());
    }

    // Check for a site ban
    if UserView::read(&conn, user_id)?.banned {
      return Err(APIError::err("site_ban").into());
    }

    let comment = Comment::read(&conn, data.comment_id)?;

    // Add to recipient ids
    match comment.parent_id {
      Some(parent_id) => {
        let parent_comment = Comment::read(&conn, parent_id)?;
        if parent_comment.creator_id != user_id {
          let parent_user = User_::read(&conn, parent_comment.creator_id)?;
          recipient_ids.push(parent_user.id);
        }
      }
      None => {
        recipient_ids.push(post.creator_id);
      }
    }

    let like_form = CommentLikeForm {
      comment_id: data.comment_id,
      post_id: data.post_id,
      user_id,
      score: data.score,
    };

    // Remove any likes first
    CommentLike::remove(&conn, &like_form)?;

    // Only add the like if the score isnt 0
    let do_add = like_form.score != 0 && (like_form.score == 1 || like_form.score == -1);
    if do_add {
      let _inserted_like = match CommentLike::like(&conn, &like_form) {
        Ok(like) => like,
        Err(_e) => return Err(APIError::err("couldnt_like_comment").into()),
      };
    }

    // Have to refetch the comment to get the current state
    let liked_comment = CommentView::read(&conn, data.comment_id, Some(user_id))?;

    Ok(CommentResponse {
      comment: liked_comment,
      recipient_ids,
    })
  }
}