//! Settings for tweaking completion.
//!
//! The fun thing here is `SnippetCap` -- this type can only be created in this
//! module, and we use to statically check that we only produce snippet
//! completions if we are allowed to.

use ide_db::helpers::insert_use::MergeBehaviour;
use rustc_hash::FxHashSet;

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct CompletionConfig {
    pub enable_postfix_completions: bool,
    pub enable_experimental_completions: bool,
    pub add_call_parenthesis: bool,
    pub add_call_argument_snippets: bool,
    pub snippet_cap: Option<SnippetCap>,
    pub merge: Option<MergeBehaviour>,
    pub resolve_capabilities: FxHashSet<CompletionResolveCapability>,
}

#[derive(Debug, Copy, Clone, Hash, Eq, PartialEq)]
pub enum CompletionResolveCapability {
    Documentation,
    Detail,
    AdditionalTextEdits,
}

impl CompletionConfig {
    pub fn allow_snippets(&mut self, yes: bool) {
        self.snippet_cap = if yes { Some(SnippetCap { _private: () }) } else { None }
    }

    pub fn should_resolve_immediately(&self) -> bool {
        !self.resolve_capabilities.contains(&CompletionResolveCapability::AdditionalTextEdits)
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct SnippetCap {
    _private: (),
}

impl Default for CompletionConfig {
    fn default() -> Self {
        CompletionConfig {
            enable_postfix_completions: true,
            enable_experimental_completions: true,
            add_call_parenthesis: true,
            add_call_argument_snippets: true,
            snippet_cap: Some(SnippetCap { _private: () }),
            merge: Some(MergeBehaviour::Full),
            resolve_capabilities: FxHashSet::default(),
        }
    }
}