const std = @import("std");
const headerPkg = @import("header");

const suffix = if (std.builtin.os.tag == .windows) ".exe" else "";
const allocator = std.heap.page_allocator;

const initialize_message = \\{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":6896,"clientInfo":{"name":"vscode","version":"1.46.1"},"rootPath":null,"rootUri":null,"capabilities":{"workspace":{"applyEdit":true,"workspaceEdit":{"documentChanges":true,"resourceOperations":["create","rename","delete"],"failureHandling":"textOnlyTransactional"},"didChangeConfiguration":{"dynamicRegistration":true},"didChangeWatchedFiles":{"dynamicRegistration":true},"symbol":{"dynamicRegistration":true,"symbolKind":{"valueSet":[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26]},"tagSupport":{"valueSet":[1]}},"executeCommand":{"dynamicRegistration":true},"configuration":true,"workspaceFolders":true},"textDocument":{"publishDiagnostics":{"relatedInformation":true,"versionSupport":false,"tagSupport":{"valueSet":[1,2]},"complexDiagnosticCodeSupport":true},"synchronization":{"dynamicRegistration":true,"willSave":true,"willSaveWaitUntil":true,"didSave":true},"completion":{"dynamicRegistration":true,"contextSupport":true,"completionItem":{"snippetSupport":true,"commitCharactersSupport":true,"documentationFormat":["markdown","plaintext"],"deprecatedSupport":true,"preselectSupport":true,"tagSupport":{"valueSet":[1]},"insertReplaceSupport":true},"completionItemKind":{"valueSet":[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25]}},"hover":{"dynamicRegistration":true,"contentFormat":["markdown","plaintext"]},"signatureHelp":{"dynamicRegistration":true,"signatureInformation":{"documentationFormat":["markdown","plaintext"],"parameterInformation":{"labelOffsetSupport":true}},"contextSupport":true},"definition":{"dynamicRegistration":true,"linkSupport":true},"references":{"dynamicRegistration":true},"documentHighlight":{"dynamicRegistration":true},"documentSymbol":{"dynamicRegistration":true,"symbolKind":{"valueSet":[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26]},"hierarchicalDocumentSymbolSupport":true,"tagSupport":{"valueSet":[1]}},"codeAction":{"dynamicRegistration":true,"isPreferredSupport":true,"codeActionLiteralSupport":{"codeActionKind":{"valueSet":["","quickfix","refactor","refactor.extract","refactor.inline","refactor.rewrite","source","source.organizeImports"]}}},"codeLens":{"dynamicRegistration":true},"formatting":{"dynamicRegistration":true},"rangeFormatting":{"dynamicRegistration":true},"onTypeFormatting":{"dynamicRegistration":true},"rename":{"dynamicRegistration":true,"prepareSupport":true},"documentLink":{"dynamicRegistration":true,"tooltipSupport":true},"typeDefinition":{"dynamicRegistration":true,"linkSupport":true},"implementation":{"dynamicRegistration":true,"linkSupport":true},"colorProvider":{"dynamicRegistration":true},"foldingRange":{"dynamicRegistration":true,"rangeLimit":5000,"lineFoldingOnly":true},"declaration":{"dynamicRegistration":true,"linkSupport":true},"selectionRange":{"dynamicRegistration":true},"semanticTokens":{"dynamicRegistration":true,"tokenTypes":["comment","keyword","number","regexp","operator","namespace","type","struct","class","interface","enum","typeParameter","function","member","macro","variable","parameter","property","label"],"tokenModifiers":["declaration","documentation","static","abstract","deprecated","readonly"]}},"window":{"workDoneProgress":true}},"trace":"off","workspaceFolders":null}}
;

const initialized_message = \\{"jsonrpc":"2.0","method":"initialized","params":{}}
;

const shutdown_message = \\{"jsonrpc":"2.0", "id":"STDWN", "method":"shutdown","params":{}}
;

fn sendRequest(req: []const u8, process: var) !void {
    try process.stdin.?.writer().print("Content-Length: {}\r\n\r\n", .{req.len});
    try process.stdin.?.writeAll(req);
}

fn readResponses(process: var) !void {
    while (true) {
        const header = headerPkg.readRequestHeader(allocator, process.stdout.?.reader()) catch |err| {
            switch(err) {
                error.EndOfStream => break,
                else => return err,
            }
        };
        defer header.deinit(allocator);

        var stdout_mem = try allocator.alloc(u8, header.content_length);
        defer allocator.free(stdout_mem);

        const stdout_bytes = stdout_mem[0..try process.stdout.?.reader().readAll(stdout_mem)];
        std.debug.print("GOT MESSAGE: {}\n", .{stdout_bytes});
    }
}

test "Open file, ask for semantic tokens" {
    var process = try std.ChildProcess.init(&[_][]const u8{ "zig-cache/bin/zls" ++ suffix }, allocator);
    defer process.deinit();
    process.stdin_behavior = .Pipe;
    process.stdout_behavior = .Pipe;
    process.stderr_behavior = std.ChildProcess.StdIo.Inherit;

    process.spawn() catch |err| {
        std.log.debug(.main, "Failed to spawn zls process, error: {}\n", .{err});
        return err;
    };

    try sendRequest(initialize_message, process);
    try sendRequest(initialized_message, process);

    const new_file_req = \\{"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"uri":"file:///test.zig","languageId":"zig","version":420,"text":"const std = @import(\"std\");"}}}
    ;
    try sendRequest(new_file_req, process);
    const sem_toks_req = \\{"jsonrpc":"2.0","id":2,"method":"textDocument/semanticTokens","params":{"textDocument":{"uri":"file:///test.zig"}}}
    ;
    try sendRequest(sem_toks_req, process);

    try sendRequest(shutdown_message, process);

    process.stdin.?.close();
    process.stdin = null;

    try readResponses(process);
    const result = try process.wait();

    // const stderr_bytes = try process.stderr.?.reader().readAllAlloc(allocator, std.math.maxInt(usize));
    // defer allocator.free(stderr_bytes);
    // if (stderr_bytes.len != 0) {
    //     std.debug.print("Stderr output\n{}\n", .{stderr_bytes});
    // }

    switch (result) {
        .Exited => |code| if (code == 0) {
            return;
        },
        else => {},
    }
    return error.ShutdownWithError;
}