// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.

// The logic of this module is heavily influenced by
// https://github.com/microsoft/vscode/blob/main/extensions/typescript-language-features/src/languageFeatures/refactor.ts

use deno_core::serde::Deserialize;
use deno_core::serde::Serialize;
use deno_core::ModuleSpecifier;
use lspower::lsp;

pub struct RefactorCodeActionKind {
  pub kind: lsp::CodeActionKind,
  matches_callback: Box<dyn Fn(&str) -> bool + Send + Sync>,
}

impl RefactorCodeActionKind {
  pub fn matches(&self, tag: &str) -> bool {
    (self.matches_callback)(tag)
  }
}

lazy_static::lazy_static! {
  pub static ref EXTRACT_FUNCTION: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_EXTRACT.as_str(), "function"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("function_")),
  };

  pub static ref EXTRACT_CONSTANT: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_EXTRACT.as_str(), "constant"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("constant_")),
  };

  pub static ref EXTRACT_TYPE: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_EXTRACT.as_str(), "type"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Extract to type alias")),
  };

  pub static ref EXTRACT_INTERFACE: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_EXTRACT.as_str(), "interface"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Extract to interface")),
  };

  pub static ref MOVE_NEWFILE: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR.as_str(), "move", "newFile"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Move to a new file")),
  };

  pub static ref REWRITE_IMPORT: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_REWRITE.as_str(), "import"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Convert namespace import") || tag.starts_with("Convert named imports")),
  };

  pub static ref REWRITE_EXPORT: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_REWRITE.as_str(), "export"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Convert default export") || tag.starts_with("Convert named export")),
  };

  pub static ref REWRITE_ARROW_BRACES: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_REWRITE.as_str(), "arrow", "braces"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Add or remove braces in an arrow function")),
  };

  pub static ref REWRITE_PARAMETERS_TO_DESTRUCTURED: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_REWRITE.as_str(), "parameters", "toDestructured"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Convert parameters to destructured object")),
  };

  pub static ref REWRITE_PROPERTY_GENERATEACCESSORS: RefactorCodeActionKind = RefactorCodeActionKind {
    kind : [lsp::CodeActionKind::REFACTOR_REWRITE.as_str(), "property", "generateAccessors"].join(".").into(),
    matches_callback: Box::new(|tag: &str| tag.starts_with("Generate 'get' and 'set' accessors")),
  };

  pub static ref ALL_KNOWN_REFACTOR_ACTION_KINDS: Vec<&'static RefactorCodeActionKind> = vec![
    &EXTRACT_FUNCTION,
    &EXTRACT_CONSTANT,
    &EXTRACT_TYPE,
    &EXTRACT_INTERFACE,
    &MOVE_NEWFILE,
    &REWRITE_IMPORT,
    &REWRITE_EXPORT,
    &REWRITE_ARROW_BRACES,
    &REWRITE_PARAMETERS_TO_DESTRUCTURED,
    &REWRITE_PROPERTY_GENERATEACCESSORS
  ];
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct RefactorCodeActionData {
  pub specifier: ModuleSpecifier,
  pub range: lsp::Range,
  pub refactor_name: String,
  pub action_name: String,
}

pub fn prune_invalid_actions(
  actions: &[lsp::CodeAction],
  number_of_invalid: usize,
) -> Vec<lsp::CodeAction> {
  let mut available_actions = Vec::<lsp::CodeAction>::new();
  let mut invalid_common_actions = Vec::<lsp::CodeAction>::new();
  let mut invalid_uncommon_actions = Vec::<lsp::CodeAction>::new();
  for action in actions {
    if action.disabled.is_none() {
      available_actions.push(action.clone());
      continue;
    }

    // These are the common refactors that we should always show if applicable.
    let action_kind =
      action.kind.as_ref().map(|a| a.as_str()).unwrap_or_default();
    if action_kind.starts_with(EXTRACT_CONSTANT.kind.as_str())
      || action_kind.starts_with(EXTRACT_FUNCTION.kind.as_str())
    {
      invalid_common_actions.push(action.clone());
      continue;
    }

    // These are the remaining refactors that we can show if we haven't reached the max limit with just common refactors.
    invalid_uncommon_actions.push(action.clone());
  }

  let mut prioritized_actions = Vec::<lsp::CodeAction>::new();
  prioritized_actions.extend(invalid_common_actions);
  prioritized_actions.extend(invalid_uncommon_actions);
  let top_n_invalid = prioritized_actions
    [0..std::cmp::min(number_of_invalid, prioritized_actions.len())]
    .to_vec();
  available_actions.extend(top_n_invalid);
  available_actions
}