import * as vscode from "vscode"
import {
    LanguageClient,
    LanguageClientOptions,
    ServerOptions,
    Executable
} from "vscode-languageclient/node"
import {
    formatCdlFile,
    completionHandlerCdl,
    hoverCdlHandler,
    formatDefFile,
    isFirstLineMachine,
    diagnosticHandler
} from "./common/handlers"

let client: LanguageClient

export function activate(context: vscode.ExtensionContext) {
    const formatCdlProvider = vscode.languages.registerDocumentFormattingEditProvider(
        { scheme: "file", language: "cdl" },
        {
            provideDocumentFormattingEdits(document: vscode.TextDocument): vscode.TextEdit[] {
                const text = document.getText()
                const formattedText = formatCdlFile(text)
                const fullRange = new vscode.Range(
                    document.positionAt(0),
                    document.positionAt(text.length)
                )
                return [vscode.TextEdit.replace(fullRange, formattedText)]
            }
        }
    )

    context.subscriptions.push(formatCdlProvider)

    const completionCdlProvider = vscode.languages.registerCompletionItemProvider(
        { scheme: "file", language: "cdl" },
        {
            provideCompletionItems(
                document: vscode.TextDocument,
                position: vscode.Position,
                token: vscode.CancellationToken,
                context: vscode.CompletionContext
            ) {
                return completionHandlerCdl(document, position)
            }
        },
        " " // Trigger completion on space
    )
    context.subscriptions.push(completionCdlProvider)

    const hoverCdlProvider = vscode.languages.registerHoverProvider(
        { scheme: "file", language: "cdl" },
        {
            provideHover(
                document: vscode.TextDocument,
                position: vscode.Position,
                token: vscode.CancellationToken
            ) {
                return hoverCdlHandler(document, position)
            }
        }
    )
    context.subscriptions.push(hoverCdlProvider)

    const formatDefProvider = vscode.languages.registerDocumentFormattingEditProvider(
        { scheme: "file", language: "def" },
        {
            provideDocumentFormattingEdits(document: vscode.TextDocument): vscode.TextEdit[] {
                const text = document.getText()
                const formattedText = formatDefFile(text)
                const fullRange = new vscode.Range(
                    document.positionAt(0),
                    document.positionAt(text.length)
                )
                return [vscode.TextEdit.replace(fullRange, formattedText)]
            }
        }
    )

    context.subscriptions.push(formatDefProvider)

    // Diagnostics collection
    const diagnosticCollectionCdl = vscode.languages.createDiagnosticCollection("cdl")
    const diagnosticCollectionDef = vscode.languages.createDiagnosticCollection("def")
    context.subscriptions.push(diagnosticCollectionCdl, diagnosticCollectionDef)

    // Check if the first line of the CDL file contains "MACHINE"
    vscode.workspace.onDidOpenTextDocument((document) => {
        if (document.languageId === "cdl" || document.languageId === "def") {
            if (document.languageId === "cdl") {
                diagnosticCollectionCdl.set(document.uri, diagnosticHandler(document))
            } else if (document.languageId === "def") {
                diagnosticCollectionDef.set(document.uri, diagnosticHandler(document))
            }
        }
    })

    vscode.workspace.onDidChangeTextDocument((event) => {
        const document = event.document
        if (document.languageId === "cdl" || document.languageId === "def") {
            if (document.languageId === "cdl") {
                diagnosticCollectionCdl.set(document.uri, diagnosticHandler(document))
            } else if (document.languageId === "def") {
                diagnosticCollectionDef.set(document.uri, diagnosticHandler(document))
            }
        }
    })
}