surreal_simple_querybuilder/

node_builder.rs

use std::fmt::Display;

pub trait ToNodeBuilder<T: Display = Self>: Display {
  fn quoted(&self) -> String {
    format!("\"{self}\"")
  }

  /// Draws the start of a relation `->node`
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "user".with("project");
  ///
  /// assert_eq!("user->project", s);
  /// ```
  fn with(&self, relation_or_node: &str) -> String {
    // write the arrow only if the first character is not a special character.
    // there are cases where the `node` string that was passed starts with
    // an arrow or a dot, in which case we do not want to push a new arrow
    // ourselves.
    if !relation_or_node.starts_with("->") && !relation_or_node.starts_with(".") {
      format!("{self}->{relation_or_node}")
    } else {
      format!("{self}{relation_or_node}")
    }
  }

  /// Draws the end of a relation `<-node`
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "user".from("project");
  ///
  /// assert_eq!("user<-project", s);
  /// ```
  fn from(&self, node: &str) -> String {
    format!("{self}<-{node}")
  }

  /// Take the current string and add in front of it the given label name as to
  /// make a string of the following format `LabelName:CurrentString`
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let label = "John".as_named_label("Account");
  ///
  /// assert_eq!(label, "Account:John");
  /// ```
  fn as_named_label(&self, label_name: &str) -> String {
    format!("{label_name}:{self}")
  }

  fn as_param(&self) -> String {
    self
      .to_string()
      .replace(".", "_")
      .replace("->", "_")
      .replace("<-", "_")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "user".equals("John");
  ///
  /// // Note that it doesn't add quotes around strings
  /// assert_eq!("user = John", s);
  /// ```
  fn equals(&self, value: &str) -> String {
    format!("{self} = {value}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "age".compares(">=", "45");
  ///
  /// assert_eq!("age >= 45", s);
  /// ```
  fn compares(&self, operator: &str, value: &str) -> String {
    format!("{self} {operator} {value}")
  }

  /// Take the current string and add the given operator plus ` $current_string` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "age".compares_parameterized(">=");
  ///
  /// assert_eq!("age >= $age", s);
  /// ```
  fn compares_parameterized(&self, operator: &str) -> String {
    format!("{self} {operator} ${}", self.as_param())
  }

  /// Take the current string and add `= $current_string` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".equals_parameterized();
  ///
  /// assert_eq!("account = $account", s);
  /// ```
  fn equals_parameterized(&self) -> String {
    format!("{self} = ${}", self.as_param())
  }

  /// Take the current string and add `+= $current_string` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".plus_equal_parameterized();
  ///
  /// assert_eq!("account += $account", s);
  /// ```
  fn plus_equal_parameterized(&self) -> String {
    format!("{self} += ${}", self.as_param())
  }

  /// Take the current string and add `> $current_string` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "age".greater_parameterized();
  ///
  /// assert_eq!("age > $age", s);
  /// ```
  fn greater_parameterized(&self) -> String {
    format!("{self} > ${}", self.as_param())
  }

  /// Take the current string and add `< $current_string` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "age".lower_parameterized();
  ///
  /// assert_eq!("age < $age", s);
  /// ```
  fn lower_parameterized(&self) -> String {
    format!("{self} < ${}", self.as_param())
  }

  /// Take the current string and add `> value` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".greater_than("5");
  ///
  /// assert_eq!("account > 5", s);
  /// ```
  fn greater_than(&self, value: &str) -> String {
    format!("{self} > {value}")
  }

  /// Take the current string and add `+= value` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "friends".plus_equal("account:john");
  ///
  /// assert_eq!("friends += account:john", s);
  /// ```
  fn plus_equal(&self, value: &str) -> String {
    format!("{self} += {value}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".contains_one("'c'");
  ///
  /// assert_eq!("account CONTAINS 'c'", s);
  /// ```
  fn contains_one(&self, value: &str) -> String {
    format!("{self} CONTAINS {value}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".contains_not("'z'");
  ///
  /// assert_eq!("account CONTAINSNOT 'z'", s);
  /// ```
  fn contains_not(&self, value: &str) -> String {
    format!("{self} CONTAINSNOT {value}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".contains_all("['a', 'c', 'u']");
  ///
  /// assert_eq!("account CONTAINSALL ['a', 'c', 'u']", s);
  /// ```
  fn contains_all(&self, values: &str) -> String {
    format!("{self} CONTAINSALL {values}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".contains_any("['a', 'c', 'u']");
  ///
  /// assert_eq!("account CONTAINSANY ['a', 'c', 'u']", s);
  /// ```
  fn contains_any(&self, values: &str) -> String {
    format!("{self} CONTAINSANY {values}")
  }

  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".contains_none("['z', 'd', 'f']");
  ///
  /// assert_eq!("account CONTAINSNONE ['z', 'd', 'f']", s);
  /// ```
  fn contains_none(&self, values: &str) -> String {
    format!("{self} CONTAINSNONE {values}")
  }

  /// Take the current string and add `as alias` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account->manage->project".as_alias("account_projects");
  ///
  /// assert_eq!("account->manage->project AS account_projects", s);
  /// ```
  fn as_alias(&self, alias: &str) -> String {
    format!("{self} AS {alias}")
  }

  /// Take the current string, extract the last segment if it is a nested property,
  /// then add parenthesis around it and add the supplied condition in them.
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let path = "account->manage->project";
  /// let s = path.filter("name = 'a_cool_project'");
  ///
  /// assert_eq!("account->manage->(project WHERE name = 'a_cool_project')", s);
  /// ```
  ///
  fn filter(&self, condition: &str) -> String {
    // This is a default implementation, but since we need the original string
    // to iterate over the chars the function does two string allocations.
    let original = self.to_string();
    let original_size = original.len();

    // this yields the size of the last segment, until a non alphanumeric character
    // is found.
    let last_segment_size = original
      .chars()
      .rev()
      .take_while(|c| c.is_alphanumeric())
      .count();

    let left = &original[..original_size - last_segment_size];
    let right = &original[original_size - last_segment_size..];

    format!("{left}({right} WHERE {condition})")
  }

  /// write a comma at the end of the string and append `right` after it.
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let select = "*".comma("<-manage<-User as authors");
  /// let query = format!("select {select} from Files");
  ///
  /// assert_eq!("select *, <-manage<-User as authors from Files", query);
  /// ```
  fn comma(&self, right: &str) -> String {
    format!("{self}, {right}")
  }

  /// write a `count()` around the current string so that it sits between the
  /// parenthesis.
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let count = "id".count();
  /// let query = format!("select {count} from Files");
  ///
  /// assert_eq!("select count(id) from Files", query);
  /// ```
  fn count(&self) -> String {
    format!("count({self})")
  }

  /// Add the supplied `id` right after the current string in order to get the a
  /// new string in the following format `current:id`
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let query = "Account".with_id("John");
  ///
  /// assert_eq!(query, "Account:John");
  /// ```
  fn with_id(&self, id: &str) -> String {
    format!("{self}:{id}")
  }

  /// Add the supplied composite `id` right after the current string in order to
  /// get the a new string in the following format `current:⟨id⟩`. The `⟨` and `⟩`
  /// are automatically added around the id, if you wish to set a regular id then
  /// refer to [with_id()](ToNodeBuilder::with_id)
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let query = "Account".with_composite_id("John/Doe");
  ///
  /// assert_eq!(query, "Account:⟨John/Doe⟩");
  /// ```
  fn with_composite_id(&self, id: &str) -> String {
    format!("{self}:⟨{id}⟩")
  }
}

impl<'a> ToNodeBuilder for &'a str {
  fn filter(&self, condition: &str) -> String {
    // unlike the default implementation of this trait function, the &str impl
    // does only one allocation.
    let original_size = self.len();

    // this yields the size of the last segment, until a non alphanumeric character
    // is found.
    let last_segment_size = self
      .chars()
      .rev()
      .take_while(|c| c.is_alphanumeric())
      .count();

    let left = &self[..original_size - last_segment_size];
    let right = &self[original_size - last_segment_size..];

    format!("{left}({right} WHERE {condition})")
  }
}

pub trait NodeBuilder<T: Display = Self>: Display {
  /// Draws the start of a relation `->node`
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "user".with("project");
  ///
  /// assert_eq!("user->project", s);
  /// ```
  fn with(&mut self, relation_or_node: &str) -> &mut String;

  /// Allows you to pass a lambda that should mutate the current string when the
  /// passed `condition` is `true`. If `condition` is `false` then the `action`
  /// lambda is ignored and the string stays intact.
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// // demonstrate how the given closure is ignored if the condition is `false`
  /// let mut label = "John".as_named_label("User");
  /// let intact = &mut label
  ///   .if_then(false, |s| s.with("LOVES").with("User"))
  ///   .with("FRIEND")
  ///   .with("User");
  ///
  /// assert_eq!("User:John->FRIEND->User", *intact);
  ///
  /// // demonstrate how the given closure is executed if the condition is `true`
  /// let mut label = "John".as_named_label("User");
  /// let modified = &mut label
  ///   .if_then(true, |s| s.with("LOVES").with("User"))
  ///   .with("FRIEND")
  ///   .with("User");
  ///
  /// assert_eq!("User:John->LOVES->User->FRIEND->User", *modified);
  /// ```
  fn if_then(&mut self, condition: bool, action: fn(&mut Self) -> &mut Self) -> &mut String;

  /// Take the current string add add `> value` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "account".greater_than("5");
  ///
  /// assert_eq!("account > 5", s);
  /// ```
  fn greater_than(&mut self, value: &str) -> &mut String;

  /// Take the current string and add `+= value` after it
  ///
  /// # Example
  /// ```
  /// use surreal_simple_querybuilder::prelude::*;
  ///
  /// let s = "friends".plus_equal("account:john");
  ///
  /// assert_eq!("friends += account:john", s);
  /// ```
  fn plus_equal(&mut self, value: &str) -> &mut String;
}

impl NodeBuilder for String {
  fn with(&mut self, node: &str) -> &mut String {
    // push the arrow only if the first character is not a special character.
    // there are cases where the `node` string that was passed starts with
    // an arrow or a dot, in which case we do not want to push a new arrow
    // ourselves.
    if !node.starts_with("->") && !node.starts_with(".") {
      self.push_str("->");
    }

    self.push_str(node);

    self
  }

  fn if_then(&mut self, condition: bool, action: fn(&mut Self) -> &mut Self) -> &mut String {
    match condition {
      true => action(self),
      false => self,
    }
  }

  fn greater_than(&mut self, value: &str) -> &mut String {
    self.push_str(" > ");
    self.push_str(value);

    self
  }

  fn plus_equal(&mut self, value: &str) -> &mut String {
    self.push_str(" += ");
    self.push_str(value);

    self
  }
}

impl ToNodeBuilder for String {}