use std::sync::Arc;
use tokio::sync::RwLock;
use tower_lsp::{LspService, Server};

mod analysis_db;
mod rebuild;

use analysis_db::SharedDb;

struct Backend {
    db: SharedDb,
}

#[tower_lsp::async_trait]
impl tower_lsp::LanguageServer for Backend {
    async fn initialize(
        &self,
        _: tower_lsp::lsp_types::InitializeParams,
    ) -> tower_lsp::jsonrpc::Result<tower_lsp::lsp_types::InitializeResult> {
        Ok(tower_lsp::lsp_types::InitializeResult {
            capabilities: tower_lsp::lsp_types::ServerCapabilities {
                text_document_sync: Some(
                    tower_lsp::lsp_types::TextDocumentSyncCapability::Kind(
                        tower_lsp::lsp_types::TextDocumentSyncKind::FULL,
                    ),
                ),
                // Declaramos capacidades desde já para evitar churn posterior.
                definition_provider: Some(tower_lsp::lsp_types::OneOf::Left(true)),
                document_symbol_provider: Some(tower_lsp::lsp_types::OneOf::Left(true)),
                workspace_symbol_provider: Some(tower_lsp::lsp_types::OneOf::Left(true)),
                hover_provider: Some(true.into()),
                references_provider: Some(tower_lsp::lsp_types::OneOf::Left(true)),
                rename_provider: Some(tower_lsp::lsp_types::OneOf::Left(true)),
                completion_provider: Some(tower_lsp::lsp_types::CompletionOptions {
                    resolve_provider: Some(false),
                    trigger_characters: Some(vec![".".into(), ":".into()]),
                    ..Default::default()
                }),
                semantic_tokens_provider: Some(
                    tower_lsp::lsp_types::SemanticTokensServerCapabilities::SemanticTokensOptions(
                        tower_lsp::lsp_types::SemanticTokensOptions {
                            legend: tower_lsp::lsp_types::SemanticTokensLegend {
                                // preenchido no PR-12
                                token_types: vec![],
                                token_modifiers: vec![],
                            },
                            full: Some(
                                tower_lsp::lsp_types::SemanticTokensFullOptions::Bool(true),
                            ),
                            range: None,
                            ..Default::default()
                        },
                    ),
                ),
                ..Default::default()
            },
            ..Default::default()
        })
    }

    async fn initialized(&self, _: tower_lsp::lsp_types::InitializedParams) {}

    async fn shutdown(&self) -> tower_lsp::jsonrpc::Result<()> {
        Ok(())
    }
}

#[tokio::main]
async fn main() {
    let stdin = tokio::io::stdin();
    let stdout = tokio::io::stdout();

    let db: SharedDb = Arc::new(RwLock::new(analysis_db::AnalysisDb::default()));

    let (service, socket) = LspService::new(|_client| Backend { db: db.clone() });
    Server::new(stdin, stdout, socket).serve(service).await;
}