use serde::{Deserialize, Serialize};

use crate::server::lsp::{
    LspMessage, RequestMarker, ResponseMarker,
    rpc::{RequestId, RequestMessageBase, ResponseMessageBase},
    textdocument::{TextDocumentIdentifier, TextEdit},
};

#[derive(Debug, Deserialize, PartialEq)]
pub struct FormattingRequest {
    #[serde(flatten)]
    base: RequestMessageBase,
    params: DocumentFormattingParams,
}

impl LspMessage for FormattingRequest {
    type Kind = RequestMarker;

    fn method(&self) -> Option<&str> {
        Some("textDocument/formatting")
    }

    fn id(&self) -> Option<&RequestId> {
        Some(&self.base.id)
    }
}

impl FormattingRequest {
    pub(crate) fn get_id(&self) -> &RequestId {
        &self.base.id
    }

    pub fn get_document_uri(&self) -> &String {
        &self.params.text_document.uri
    }

    pub(crate) fn get_options(&self) -> &FormattingOptions {
        &self.params.options
    }
}

#[derive(Debug, Deserialize, PartialEq)]
#[serde(rename_all = "camelCase")]
struct DocumentFormattingParams {
    text_document: TextDocumentIdentifier,
    options: FormattingOptions,
}

#[derive(Debug, Deserialize, PartialEq)]
#[serde(rename_all = "camelCase")]
pub struct FormattingOptions {
    pub tab_size: u8,
    pub insert_spaces: bool,
    // TODO: further options
}

#[derive(Debug, Serialize, PartialEq)]
pub struct FormattingResponse {
    #[serde(flatten)]
    base: ResponseMessageBase,
    result: Vec<TextEdit>,
}

impl LspMessage for FormattingResponse {
    type Kind = ResponseMarker;

    fn method(&self) -> Option<&str> {
        Some("textDocument/formatting")
    }

    fn id(&self) -> Option<&RequestId> {
        self.base.request_id()
    }
}

impl FormattingResponse {
    pub(crate) fn new(id: &RequestId, text_edits: Vec<TextEdit>) -> Self {
        Self {
            base: ResponseMessageBase::success(id),
            result: text_edits,
        }
    }
}

#[cfg(test)]
mod tests {
    use crate::server::lsp::{
        FormattingResponse,
        messages::textdocument_formatting::{DocumentFormattingParams, FormattingOptions},
        rpc::{Message, RequestId, RequestMessageBase},
        textdocument::{Range, TextDocumentIdentifier, TextEdit},
    };

    use super::FormattingRequest;

    #[test]
    fn deserialize() {
        let message = br#"{"jsonrpc":"2.0","method":"textDocument/formatting","id":2,"params":{"textDocument":{"uri":"file:///dings"},"options":{"tabSize":2,"insertSpaces":true}}}"#;
        let request = serde_json::from_slice::<FormattingRequest>(message).unwrap();

        assert_eq!(
            request,
            FormattingRequest {
                base: RequestMessageBase {
                    base: Message {
                        jsonrpc: "2.0".to_string(),
                    },
                    method: "textDocument/formatting".to_string(),
                    id: RequestId::Integer(2)
                },
                params: DocumentFormattingParams {
                    text_document: TextDocumentIdentifier {
                        uri: "file:///dings".to_string()
                    },
                    options: FormattingOptions {
                        tab_size: 2,
                        insert_spaces: true
                    }
                }
            }
        );
    }

    #[test]
    fn serialize() {
        let text_edits = vec![TextEdit::new(Range::new(0, 1, 2, 3), "dings")];
        let formatting_response = FormattingResponse::new(&RequestId::Integer(42), text_edits);
        let expected_message = r#"{"jsonrpc":"2.0","id":42,"result":[{"range":{"start":{"line":0,"character":1},"end":{"line":2,"character":3}},"newText":"dings"}]}"#;
        assert_eq!(
            serde_json::to_string(&formatting_response).unwrap(),
            expected_message
        );
    }
}
