use crate::sources::*;
use crate::completion::keyword::*;
use flexi_logger::LoggerHandle;
#[allow(unused)]
use log::{debug, info, warn};
use once_cell::sync::OnceCell;
use serde::{Deserialize, Serialize};
use std::string::ToString;
use std::sync::{Arc, Mutex, RwLock};
use tower_lsp::jsonrpc::Result;
use tower_lsp::lsp_types::*;
use tower_lsp::{Client, LanguageServer};

pub static GLOBAL_BACKEND: OnceCell<Arc<Backend>> = OnceCell::new();

pub struct LSPServer {
    pub srcs: Sources,
    pub key_comps: Vec<CompletionItem>,
    pub sys_tasks: Vec<CompletionItem>,
    pub directives: Vec<CompletionItem>,
    pub conf: RwLock<ProjectConfig>,
    #[allow(unused)]
    pub log_handle: Mutex<Option<LoggerHandle>>,
}

impl LSPServer {
    pub fn new(log_handle: Option<LoggerHandle>) -> LSPServer {
        LSPServer {
            srcs: Sources::new(),
            key_comps: keyword_completions(KEYWORDS),
            sys_tasks: other_completions(SYS_TASKS),
            directives: other_completions(DIRECTIVES),
            conf: RwLock::new(ProjectConfig::default()),
            log_handle: Mutex::new(log_handle),
        }
    }
}

pub struct Backend {
    pub client: Client,
    pub server: LSPServer
}


impl Backend {
    pub fn new(client: Client, log_handle: LoggerHandle) -> Backend {
        Backend {
            client,
            server: LSPServer::new(Some(log_handle)),
        }
    }
}

#[derive(strum_macros::Display, Debug, Serialize, Deserialize)]
pub enum LogLevel {
    #[strum(serialize = "error")]
    Error,
    #[strum(serialize = "warn")]
    Warn,
    #[strum(serialize = "info")]
    Info,
    #[strum(serialize = "debug")]
    Debug,
    #[strum(serialize = "trace")]
    Trace,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(default)]
pub struct ProjectConfig {
    // if true, recursively search the working directory for files to run diagnostics on
    pub auto_search_workdir: bool,
    // list of directories with header files
    pub include_dirs: Vec<String>,
    // list of directories to recursively search for SystemVerilog/Verilog sources
    pub source_dirs: Vec<String>,
    // config options for verible tools
    pub verible: Verible,
    // config options for verilator tools
    pub verilator: Verilator,
    // log level
    pub log_level: LogLevel,
}

impl Default for ProjectConfig {
    fn default() -> Self {
        ProjectConfig {
            auto_search_workdir: true,
            include_dirs: Vec::new(),
            source_dirs: Vec::new(),
            verible: Verible::default(),
            verilator: Verilator::default(),
            log_level: LogLevel::Info,
        }
    }
}

#[derive(Default, Debug, Serialize, Deserialize)]
#[serde(default)]
pub struct Verible {
    pub syntax: VeribleSyntax,
    pub format: VeribleFormat,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(default)]
pub struct VeribleSyntax {
    pub enabled: bool,
    pub path: String,
    pub args: Vec<String>,
}

impl Default for VeribleSyntax {
    fn default() -> Self {
        Self {
            enabled: true,
            path: "verible-verilog-syntax".to_string(),
            args: Vec::new(),
        }
    }
}

#[derive(Debug, Default, Serialize, Deserialize)]
#[serde(default)]
pub struct Verilator {
    pub syntax: VerilatorSyntax,
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(default)]
pub struct VerilatorSyntax {
    pub enabled: bool,
    pub path: String,
    pub args: Vec<String>,
}

impl Default for VerilatorSyntax {
    fn default() -> Self {
        Self {
            enabled: true,
            path: "verilator".to_string(),
            args: vec![
                "--lint-only".to_string(),
                "--sv".to_string(),
                "-Wall".to_string(),
            ],
        }
    }
}

#[derive(Debug, Serialize, Deserialize)]
#[serde(default)]
pub struct VeribleFormat {
    pub enabled: bool,
    pub path: String,
    pub args: Vec<String>,
}

impl Default for VeribleFormat {
    fn default() -> Self {
        Self {
            enabled: true,
            path: "verible-verilog-format".to_string(),
            args: Vec::new(),
        }
    }
}


#[tower_lsp::async_trait]
impl LanguageServer for Backend {
    async fn initialize(&self, _: InitializeParams) -> Result<InitializeResult> {
        self.server.srcs.init();

        // 申明 LSP 的基本信息和提供的能力
        let server_info = Some(ServerInfo {
            name: "Digital IDE 专用 LSP 后端服务器".to_string(),
            version: Some("0.4.0".to_string())
        });

        let text_document_sync = TextDocumentSyncCapability::Options(
            TextDocumentSyncOptions {
                open_close: Some(true),
                change: Some(TextDocumentSyncKind::INCREMENTAL),
                will_save: None,
                will_save_wait_until: None,
                save: Some(TextDocumentSyncSaveOptions::SaveOptions(SaveOptions {
                    include_text: None,
                })),
            }
        );
        
        let completion_provider = CompletionOptions {
            resolve_provider: Some(false),
            trigger_characters: Some(vec![
                ".".to_string(),
                "$".to_string(),
                "`".to_string(),
            ]),
            work_done_progress_options: WorkDoneProgressOptions {
                work_done_progress: None,
            },
            all_commit_characters: None,
            // TODO: 检查这里的选项
            completion_item: None,
        };

        let capabilities = ServerCapabilities {
            text_document_sync: Some(text_document_sync),
            completion_provider: Some(completion_provider),
            definition_provider: Some(OneOf::Left(true)),
            hover_provider: Some(HoverProviderCapability::Simple(true)),
            document_symbol_provider: Some(OneOf::Left(true)),
            document_highlight_provider: Some(OneOf::Left(true)),
            ..ServerCapabilities::default()
        };

        Ok(InitializeResult { server_info, capabilities })
    }
    
    async fn initialized(&self, _: InitializedParams) {
        self.client
            .log_message(MessageType::INFO, "digital lsp initialized!")
            .await;

        // self.client.send_notification::<StringNotification>(StringNotification { content: "hello from lsp server".to_string() }).await;
    }
    
    async fn shutdown(&self) -> Result<()> {
        Ok(())
    }

    async fn did_open(&self, params: DidOpenTextDocumentParams) {
        let diagnostics = self.server.did_open(params);
        self.client
            .publish_diagnostics(
                diagnostics.uri,
                diagnostics.diagnostics,
                diagnostics.version,
            )
            .await;
    }
    
    async fn did_change(&self, params: DidChangeTextDocumentParams) {
        self.server.did_change(params);
    }

    async fn did_save(&self, params: DidSaveTextDocumentParams) {
        let diagnostics = self.server.did_save(params);
        self.client
            .publish_diagnostics(
                diagnostics.uri,
                diagnostics.diagnostics,
                diagnostics.version,
            )
            .await;
    }


    async fn completion(&self, params: CompletionParams) -> Result<Option<CompletionResponse>> {
        Ok(self.server.completion(params))
    }

    async fn goto_definition(
        &self,
        params: GotoDefinitionParams,
    ) -> Result<Option<GotoDefinitionResponse>> {
        Ok(self.server.goto_definition(params))
    }
    
    async fn hover(&self, params: HoverParams) -> Result<Option<Hover>> {
        
        Ok(self.server.hover(params))
    }

    async fn document_symbol(
        &self,
        params: DocumentSymbolParams,
    ) -> Result<Option<DocumentSymbolResponse>> {
        Ok(self.server.document_symbol(params))
    }

    async fn formatting(&self, params: DocumentFormattingParams) -> Result<Option<Vec<TextEdit>>> {
        Ok(self.server.formatting(params))
    }

    async fn range_formatting(
        &self,
        params: DocumentRangeFormattingParams,
    ) -> Result<Option<Vec<TextEdit>>> {
        Ok(self.server.range_formatting(params))
    }

    async fn document_highlight(
        &self,
        params: DocumentHighlightParams,
    ) -> Result<Option<Vec<DocumentHighlight>>> {
        Ok(self.server.document_highlight(params))
    }
}