module Fx::Statements

Create a new database function.

@param name [String, Symbol] The name of the database function. @param version [Fixnum] The version number of the function, used to

find the definition file in `db/functions`. This defaults to `1` if
not provided.

@param sql_definition [String] The SQL query for the function schema.

If both `sql_definition` and `version` are provided,
`sql_definition` takes prescedence.

@return The database response from executing the create statement.

@example Create from `db/functions/uppercase_users_name_v02.sql`

create_function(:uppercase_users_name, version: 2)

@example Create from provided SQL string

create_function(:uppercase_users_name, sql_definition: <<~SQL)
  CREATE OR REPLACE FUNCTION uppercase_users_name()
  RETURNS trigger AS $$
  BEGIN
    NEW.upper_name = UPPER(NEW.name);
    RETURN NEW;
  END;
  $$ LANGUAGE plpgsql;
SQL

# File lib/fx/statements.rb, line 29
def create_function(name, options = {})
  version = options.fetch(:version, 1)
  sql_definition = options[:sql_definition]

  if version.nil? && sql_definition.nil?
    raise(
      ArgumentError,
      "version or sql_definition must be specified"
    )
  end
  sql_definition = sql_definition.strip_heredoc if sql_definition
  sql_definition ||= Fx::Definition.function(name: name, version: version).to_sql

  Fx.database.create_function(sql_definition)
end

Create a new database trigger.

@param name [String, Symbol] The name of the database trigger. @param version [Fixnum] The version number of the trigger, used to

find the definition file in `db/triggers`. This defaults to `1` if
not provided.

@param sql_definition [String] The SQL query for the function. An error

will be raised if `sql_definition` and `version` are both set,
as they are mutually exclusive.

@return The database response from executing the create statement.

@example Create trigger from `db/triggers/uppercase_users_name_v01.sql`

create_trigger(:uppercase_users_name, version: 1)

@example Create trigger from provided SQL string

create_trigger(:uppercase_users_name, sql_definition: <<~SQL)
  CREATE TRIGGER uppercase_users_name
      BEFORE INSERT ON users
      FOR EACH ROW
      EXECUTE FUNCTION uppercase_users_name();
 SQL

# File lib/fx/statements.rb, line 128
def create_trigger(name, options = {})
  version = options[:version]
  _on = options[:on]
  sql_definition = options[:sql_definition]

  if version.present? && sql_definition.present?
    raise(
      ArgumentError,
      "sql_definition and version cannot both be set"
    )
  end

  if version.nil?
    version = 1
  end

  sql_definition = sql_definition.strip_heredoc if sql_definition
  sql_definition ||= Fx::Definition.trigger(name: name, version: version).to_sql

  Fx.database.create_trigger(sql_definition)
end

Drop a database function by name.

@param name [String, Symbol] The name of the database function. @param revert_to_version [Fixnum] Used to reverse the `drop_function`

command on `rake db:rollback`. The provided version will be passed as
the `version` argument to {#create_function}.

@return The database response from executing the drop statement.

@example Drop a function, rolling back to version 2 on rollback

drop_function(:uppercase_users_name, revert_to_version: 2)

# File lib/fx/statements.rb, line 56
def drop_function(name, options = {})
  Fx.database.drop_function(name)
end

Drop a database trigger by name.

@param name [String, Symbol] The name of the database trigger. @param on [String, Symbol] The name of the table the database trigger

is associated with.

@param revert_to_version [Fixnum] Used to reverse the `drop_trigger`

command on `rake db:rollback`. The provided version will be passed as
the `version` argument to {#create_trigger}.

@return The database response from executing the drop statement.

@example Drop a trigger, rolling back to version 3 on rollback

drop_trigger(:log_inserts, on: :users, revert_to_version: 3)

# File lib/fx/statements.rb, line 163
def drop_trigger(name, options = {})
  on = options.fetch(:on)
  Fx.database.drop_trigger(name, on: on)
end

Update a database function.

@param name [String, Symbol] The name of the database function. @param version [Fixnum] The version number of the function, used to

find the definition file in `db/functions`. This defaults to `1` if
not provided.

@param sql_definition [String] The SQL query for the function schema.

If both `sql_definition` and `version` are provided,
`sql_definition` takes prescedence.

@return The database response from executing the create statement.

@example Update function to a given version

update_function(
  :uppercase_users_name,
  version: 3,
  revert_to_version: 2,
)

@example Update function from provided SQL string

update_function(:uppercase_users_name, sql_definition: <<~SQL)
  CREATE OR REPLACE FUNCTION uppercase_users_name()
  RETURNS trigger AS $$
  BEGIN
    NEW.upper_name = UPPER(NEW.name);
    RETURN NEW;
  END;
  $$ LANGUAGE plpgsql;
SQL

# File lib/fx/statements.rb, line 89
def update_function(name, options = {})
  version = options[:version]
  sql_definition = options[:sql_definition]

  if version.nil? && sql_definition.nil?
    raise(
      ArgumentError,
      "version or sql_definition must be specified"
    )
  end

  sql_definition = sql_definition.strip_heredoc if sql_definition
  sql_definition ||= Fx::Definition.function(name: name, version: version).to_sql

  Fx.database.update_function(name, sql_definition)
end

Update a database trigger to a new version.

The existing trigger is dropped and recreated using the supplied `on` and `version` parameter.

@param name [String, Symbol] The name of the database trigger. @param version [Fixnum] The version number of the trigger. @param on [String, Symbol] The name of the table the database trigger

is associated with.

@param sql_definition [String] The SQL query for the function. An error

will be raised if `sql_definition` and `version` are both set,
as they are mutually exclusive.

@param revert_to_version [Fixnum] The version number to rollback to on

`rake db rollback`

@return The database response from executing the create statement.

@example Update trigger to a given version

update_trigger(
  :log_inserts,
  on: :users,
  version: 3,
  revert_to_version: 2,
)

@example Update trigger from provided SQL string

update_trigger(:uppercase_users_name, sql_definition: <<~SQL)
  CREATE TRIGGER uppercase_users_name
      BEFORE INSERT ON users
      FOR EACH ROW
      EXECUTE FUNCTION uppercase_users_name();
 SQL

# File lib/fx/statements.rb, line 200
def update_trigger(name, options = {})
  version = options[:version]
  on = options[:on]
  sql_definition = options[:sql_definition]

  if version.nil? && sql_definition.nil?
    raise(
      ArgumentError,
      "version or sql_definition must be specified"
    )
  end

  if version.present? && sql_definition.present?
    raise(
      ArgumentError,
      "sql_definition and version cannot both be set"
    )
  end

  if on.nil?
    raise ArgumentError, "on is required"
  end

  sql_definition = sql_definition.strip_heredoc if sql_definition
  sql_definition ||= Fx::Definition.trigger(name: name, version: version).to_sql

  Fx.database.update_trigger(
    name,
    on: on,
    sql_definition: sql_definition
  )
end