import fs from 'fs';
import * as process from 'process';
import { getDiagnostics, type GetDiagnosticsReturn } from './parser';
import { add_personal } from './languagetool';

export function log(str: string) {
  fs.appendFileSync('/tmp/latex-lsp-test', str + "\n");
}

export function error(str: string) {
  log("ERROR:" + str);
  process.exit(1);
}

let init = false;

type RPCResult = {
  jsonrpc: string,
  id: string,
} & ({
  result: any,
} | {
  error: any,
})

type RPCRequest = {
  id: string;
  jsonrpc: string,
  method: string,
  params: any,
}

// ASSUMES that is has the right format
function sendRPC(obj: any) {
  const msg = JSON.stringify(obj);
  const buff = Buffer.from(msg, 'utf-8');

  const fullmessage = `Content-Length: ${buff.byteLength}\r\n\r\n${msg}`;

  log("Sending message: " + fullmessage.replace(/\n/g, '\\n').replace(/\r/g, '\\r'))

  process.stdout.cork()
  process.stdout.write(fullmessage);
  process.stdout.uncork();
}

function sendRPCMessage(req: RPCRequest, result: any = undefined, error: any = undefined) {
  if (!result && !error) {
    error("Invalid rpc message to send")
    return;
  }

  sendRPC({
    id: req.id,
    jsonrpc: req.jsonrpc,
    result,
    error
  } as RPCResult)
}

function notifyRPC(method: string, params: any) {
  sendRPC({
    jsonrpc: '2.0',
    method,
    params,
  })
}

type TextDocumentDidOpen = RPCRequest & {
  method: 'textDocument/didOpen',
  params: {
    textDocument: {
      uri: string;
      languageId: string;
      version: number;
      text: string;
    }
  }
}

type TextDocumentCodeAction = RPCRequest & {
  method: 'textDocument/codeAction',
  params: {
    range: Range,
    textDocument: {
      uri: string,
    }
  },
};

type WorkspaceExecuteCommand = RPCRequest & {
  method: 'workspace/executeCommand',
  params: {
    command: string,
    arguments: any[]
  }

}

type Position = {
  line: number,
  character: number
}

type Range = {
  start: Position,
  end: Position,
}

export type Dialog = {
  range: Range,
  message: string,
  severity: Severity,
  data?: any,
}

export enum Severity {
  Error = 1,
  Warning = 2,
  Information = 3,
  Hint = 4,
}

let lastRequest: null | Date = null;

const saveRes: Record<string, GetDiagnosticsReturn[]> = {};

async function request(file: string, uri: string) {
  if (lastRequest) {
    if (((new Date()).getTime() - lastRequest.getTime()) <= 60 * 1000) {
      return;
    }
  }
  lastRequest = new Date();
  let diags = await getDiagnostics(file);

  saveRes[uri] = diags;

  const params = {
    uri: uri,
    diagnostics: diags.map((a, i) => ({
      message: a.message,
      range: a.range,
      severity: a.severity,
      data: i,
    }) as Dialog),
  }

  notifyRPC('textDocument/publishDiagnostics', params);

  return diags;
}


async function handleJSON(req: RPCRequest) {
  log(`New Message entered: method: ${req.method}`);

  if (init) {
    if (req.method === 'initialized') {
      // On init confirm do nothing
      return;
    } else if (req.method === 'textDocument/didOpen') {
      const reqO: TextDocumentDidOpen = req as any;

      if (reqO.params.textDocument.languageId !== 'latex') {
        error(`This server only supports latex! Got: ${reqO.params.textDocument.languageId}`)
        return;
      }

      request(reqO.params.textDocument.text, reqO.params.textDocument.uri);

      //error(`TODO ${req.method}`);
    } else if (req.method === 'textDocument/codeAction') {
      const reqO: TextDocumentCodeAction = req as any;

      const diagRecord = saveRes[reqO.params.textDocument.uri];

      if (!diagRecord) {
        sendRPCMessage(req, [{
          title: "File does not seam to be loaded"
        }]);
        return;
      }

      const saved = saveRes[req.params.textDocument.uri];

      const character = req.params.range.start.character;
      const line = req.params.range.start.line;

      if (!req.params.context?.diagnostics[0]) {
        sendRPCMessage(req, [{
          title: "No diagnostics found in this file"
        }]);
        return;
      }

      let item: GetDiagnosticsReturn | undefined = undefined;

      console.log(JSON.stringify(req.params) + "\n\n\n");
      console.log(JSON.stringify(req.params.context.diagnostics[0]) + "\n\n\n");

      if (typeof req.params.context?.diagnostics[0].data != 'number') {
        for (const _item of saved) {
          if (_item.range.end.line >= line && _item.range.start.line <= line) {
            if (_item.range.end.character >= character && _item.range.start.character <= line) {
              item = _item as GetDiagnosticsReturn;
              break;
            }
          }
        }
      } else {
        console.log("Using " + req.params.context.diagnostics[0].data)
        item = saved[req.params.context.diagnostics[0].data];
      }

      if (item === undefined) {
        sendRPCMessage(req, [{
          title: "No diagnostics found in this file"
        }]);
        return;
      }

      if (item.replacements.length === 0) {
        sendRPCMessage(req, [{
          title: item.message,
        }]);
        return;
      }
      
      const items: {
        title: string,
        edit?: {
          changes: Record<string, { range: Range, newText: string }[]>
        },
        command?: {
          title: string,
          command: string,
          arguments?: any[]
        },
      }[] = item.replacements.map((value) => (
        {
          title: value,
          edit: {
            changes: {
              [reqO.params.textDocument.uri]: [
                {
                  range: reqO.params.context.diagnostics[0].range,
                  newText: value
                }
              ]
            }
          }
        }
      ));

      if (item.rule_id.startsWith("MORFOLOGIK_RULE")) {
        items.push({
          title: "Add to personal dictinoary",
          command: {
            title: "Add to personal dictionary",
            command: "add_to_dic",
            arguments: [
              reqO.params.textDocument.uri,
              item.word,
            ]
          }
        });
      }

      sendRPCMessage(req, items);
      return;
    } else if (req.method === 'workspace/executeCommand') {
      let reqO: WorkspaceExecuteCommand = req as any;

      log(JSON.stringify(req.params));

      if (reqO.params.command === 'add_to_dic') {
        if (reqO.params.arguments[0] && reqO.params.arguments[1]) {
          await add_personal([reqO.params.arguments[1]]);
        }
        return;
      }

      error(`TODO Handle: ${req.method} ${JSON.stringify(req.params)}`);
    } else {
      error(`Handle: ${req.method} after init`);
    }
  } else {
    if (req.method === 'initialize') {
      log("Recived init");

      init = true;

      log(JSON.stringify(req));

      sendRPCMessage(req, {
        capabilities: {
          diagnosticProvider: {
            // TODO change in the future when the server also checks the ib file as well
            interFileDependencies: false,
            workspaceDiagnostics: false,
          },
          codeActionProvider: {
            codeActionKinds: ["quickfix"],

            resolveSupport: {
              properties: ["edit"],
            },
          },
          executeCommandProvider: {
            commands: [
              "add_to_dic"
            ]
          }
        },
        serverInfo: {
          name: "Super Cool latex server",
          version: "1.0.0",
        }
      });

      return;
    } else {
      error(`Expected init method found '${req.method}'`)
    }
  }
}


export function handleData(data: Buffer) {
  let strData = data.toString();
  let jsonData = strData.split('\n');

  let req: RPCRequest;

  if (jsonData.length === 3) {
    try {
      req = JSON.parse(jsonData[2]);
    } catch (e) {
      log("Failed to parse json 1/2! Msg:\n");
      log(strData.replace(/\n/g, '\\n').replace(/\r/g, '\\r'));
      log("\n\nFailed to parse json 2/2! JSON Line:\n");
      log(jsonData[2]);
      return;
    }
    handleJSON(req);
    return;
  }

  for (let i = 2; i < jsonData.length; i += 2) {

    let jsonLine = jsonData[i];
    if (i != jsonData.length - 1) {
      let index = jsonLine.indexOf('Content-Length');
      if (index == -1) {
        error("Handling multiline expected 'Content-Length'");
        return;
      }

      try {
        req = JSON.parse(jsonLine.substring(0, index));
      } catch (e) {
        log("Failed to parse json 1/2! Msg:\n");
        log(strData.replace(/\n/g, '\\n').replace(/\r/g, '\\r'));
        log("\n\nFailed to parse json 2/2! JSON Line:\n");
        log(jsonLine.substring(0, index));
        return;
      }
    } else {
      try {
        req = JSON.parse(jsonLine);
      } catch (e) {
        log("Failed to parse json 1/2! Msg:\n");
        log(strData.replace(/\n/g, '\\n').replace(/\r/g, '\\r'));
        log("\n\nFailed to parse json 2/2! JSON Line:\n");
        log(jsonLine);
        return;
      }

    }

    handleJSON(req);
  }
}