feat(render): implement choice extension. #850

espanso-render/src/extension/choice.rs

@@ -0,0 +1,132 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use anyhow::Result;
+use log::error;
+use thiserror::Error;
+
+use crate::{Extension, ExtensionOutput, ExtensionResult, Params, Value};
+
+pub trait ChoiceSelector {
+  fn show(&self, choices: &[Choice]) -> ChoiceSelectorResult;
+}
+
+#[derive(Debug, Clone)]
+pub struct Choice<'a> {
+  pub label: &'a str,
+  pub id: &'a str,
+}
+
+pub enum ChoiceSelectorResult {
+  Success(String),
+  Aborted,
+  Error(anyhow::Error),
+}
+
+pub struct ChoiceExtension<'a> {
+  selector: &'a dyn ChoiceSelector,
+}
+
+#[allow(clippy::new_without_default)]
+impl<'a> ChoiceExtension<'a> {
+  pub fn new(selector: &'a dyn ChoiceSelector) -> Self {
+    Self { selector }
+  }
+}
+
+impl<'a> Extension for ChoiceExtension<'a> {
+  fn name(&self) -> &str {
+    "choice"
+  }
+
+  fn calculate(
+    &self,
+    _: &crate::Context,
+    _: &crate::Scope,
+    params: &Params,
+  ) -> crate::ExtensionResult {
+    let choices: Vec<Choice> = if let Some(Value::String(values)) = params.get("values") {
+      values
+        .lines()
+        .filter_map(|line| {
+          let trimmed_line = line.trim();
+          if !trimmed_line.is_empty() {
+            Some(trimmed_line)
+          } else {
+            None
+          }
+        })
+        .map(|line| Choice {
+          label: line,
+          id: line,
+        })
+        .collect()
+    } else if let Some(Value::Array(values)) = params.get("values") {
+      let choices: Result<Vec<Choice>> = values
+        .iter()
+        .map(|value| match value {
+          Value::String(string) => Ok(Choice {
+            id: string,
+            label: string,
+          }),
+          Value::Object(fields) => Ok(Choice {
+            id: fields
+              .get("id")
+              .and_then(|val| val.as_string())
+              .ok_or(ChoiceError::InvalidObjectValue)?,
+            label: fields
+              .get("label")
+              .and_then(|val| val.as_string())
+              .ok_or(ChoiceError::InvalidObjectValue)?,
+          }),
+          _ => Err(ChoiceError::InvalidValueType.into()),
+        })
+        .collect();
+
+      match choices {
+        Ok(choices) => choices,
+        Err(err) => {
+          return crate::ExtensionResult::Error(err);
+        }
+      }
+    } else {
+      return crate::ExtensionResult::Error(ChoiceError::MissingValues.into());
+    };
+
+    match self.selector.show(&choices) {
+      ChoiceSelectorResult::Success(choice_id) => {
+        ExtensionResult::Success(ExtensionOutput::Single(choice_id))
+      }
+      ChoiceSelectorResult::Aborted => ExtensionResult::Aborted,
+      ChoiceSelectorResult::Error(error) => ExtensionResult::Error(error),
+    }
+  }
+}
+
+#[derive(Error, Debug)]
+pub enum ChoiceError {
+  #[error("missing values parameter")]
+  MissingValues,
+
+  #[error("values contain object items, but they are missing either the 'id' or 'label' fields")]
+  InvalidObjectValue,
+
+  #[error("values contain an invalid item type. items can only be strings or objects")]
+  InvalidValueType,
+}

espanso-render/src/extension/mod.rs

@@ -17,6 +17,7 @@
  * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+pub mod choice;
 pub mod clipboard;
 pub mod date;
 pub mod echo;