const std = @import("std");
// LSP types
const json = std.json;

pub const Position = struct {
    line: i64,
    character: i64,
};

pub const Range = struct {
    start: Position,
    end: Position,
};

pub const Location = struct {
    uri: []const u8,
    range: Range,
};

/// Id of a request
pub const RequestId = union(enum) {
    String: []const u8,
    Integer: i64,
    Float: f64,
};

/// Hover response
pub const Hover = struct {
    contents: MarkupContent,
};

/// Params of a response (result)
pub const ResponseParams = union(enum) {
    CompletionList: CompletionList,
    Location: Location,
    Hover: Hover,
    DocumentSymbols: []DocumentSymbol,
    SemanticTokensFull: struct { data: []const u32 },
    TextEdits: []TextEdit,
    Locations: []Location,
    WorkspaceEdit: WorkspaceEdit,
    InitializeResult: InitializeResult,
};

/// JSONRPC notifications
pub const Notification = struct {
    pub const Params = union(enum) {
        LogMessage: struct {
            type: MessageType,
            message: []const u8,
        },
        PublishDiagnostics: struct {
            uri: []const u8,
            diagnostics: []Diagnostic,
        },
        ShowMessage: struct {
            type: MessageType,
            message: []const u8,
        },
    };

    jsonrpc: []const u8 = "2.0",
    method: []const u8,
    params: Params,
};

/// JSONRPC response
pub const Response = struct {
    jsonrpc: []const u8 = "2.0",
    id: RequestId,
    result: ResponseParams,
};

/// Type of a debug message
pub const MessageType = enum(i64) {
    Error = 1,
    Warning = 2,
    Info = 3,
    Log = 4,

    pub fn jsonStringify(
        value: MessageType,
        options: json.StringifyOptions,
        out_stream: anytype,
    ) !void {
        try json.stringify(@enumToInt(value), options, out_stream);
    }
};

pub const DiagnosticSeverity = enum(i64) {
    Error = 1,
    Warning = 2,
    Information = 3,
    Hint = 4,

    pub fn jsonStringify(
        value: DiagnosticSeverity,
        options: json.StringifyOptions,
        out_stream: anytype,
    ) !void {
        try json.stringify(@enumToInt(value), options, out_stream);
    }
};

pub const Diagnostic = struct {
    range: Range,
    severity: DiagnosticSeverity,
    code: []const u8,
    source: []const u8,
    message: []const u8,
};

pub const TextDocument = struct {
    uri: []const u8,
    // This is a substring of mem starting at 0
    text: []const u8,
    // This holds the memory that we have actually allocated.
    mem: []u8,
};

pub const WorkspaceEdit = struct {
    changes: ?std.StringHashMap([]TextEdit),

    pub fn jsonStringify(
        self: WorkspaceEdit,
        options: std.json.StringifyOptions,
        writer: anytype,
    ) @TypeOf(writer).Error!void {
        try writer.writeByte('{');
        if (self.changes) |changes| {
            try writer.writeAll("\"changes\": {");
            var it = changes.iterator();
            var idx: usize = 0;
            while (it.next()) |entry| : (idx += 1) {
                if (idx != 0) try writer.writeAll(", ");

                try writer.writeByte('"');
                try writer.writeAll(entry.key);
                try writer.writeAll("\":");
                try std.json.stringify(entry.value, options, writer);
            }
            try writer.writeByte('}');
        }
        try writer.writeByte('}');
    }
};

pub const TextEdit = struct {
    range: Range,
    newText: []const u8,
};

pub const MarkupContent = struct {
    pub const Kind = enum(u1) {
        PlainText = 0,
        Markdown = 1,

        pub fn jsonStringify(
            value: Kind,
            options: json.StringifyOptions,
            out_stream: anytype,
        ) !void {
            const str = switch (value) {
                .PlainText => "plaintext",
                .Markdown => "markdown",
            };
            try json.stringify(str, options, out_stream);
        }
    };

    kind: Kind = .Markdown,
    value: []const u8,
};

pub const CompletionList = struct {
    isIncomplete: bool,
    items: []const CompletionItem,
};

pub const InsertTextFormat = enum(i64) {
    PlainText = 1,
    Snippet = 2,

    pub fn jsonStringify(
        value: InsertTextFormat,
        options: json.StringifyOptions,
        out_stream: anytype,
    ) !void {
        try json.stringify(@enumToInt(value), options, out_stream);
    }
};

pub const CompletionItem = struct {
    const Kind = enum(i64) {
        Text = 1,
        Method = 2,
        Function = 3,
        Constructor = 4,
        Field = 5,
        Variable = 6,
        Class = 7,
        Interface = 8,
        Module = 9,
        Property = 10,
        Unit = 11,
        Value = 12,
        Enum = 13,
        Keyword = 14,
        Snippet = 15,
        Color = 16,
        File = 17,
        Reference = 18,
        Folder = 19,
        EnumMember = 20,
        Constant = 21,
        Struct = 22,
        Event = 23,
        Operator = 24,
        TypeParameter = 25,

        pub fn jsonStringify(
            value: Kind,
            options: json.StringifyOptions,
            out_stream: anytype,
        ) !void {
            try json.stringify(@enumToInt(value), options, out_stream);
        }
    };

    label: []const u8,
    kind: Kind,
    textEdit: ?TextEdit = null,
    filterText: ?[]const u8 = null,
    insertText: ?[]const u8 = null,
    insertTextFormat: ?InsertTextFormat = .PlainText,
    detail: ?[]const u8 = null,
    documentation: ?MarkupContent = null,
};

pub const DocumentSymbol = struct {
    const Kind = enum {
        File = 1,
        Module = 2,
        Namespace = 3,
        Package = 4,
        Class = 5,
        Method = 6,
        Property = 7,
        Field = 8,
        Constructor = 9,
        Enum = 10,
        Interface = 11,
        Function = 12,
        Variable = 13,
        Constant = 14,
        String = 15,
        Number = 16,
        Boolean = 17,
        Array = 18,
        Object = 19,
        Key = 20,
        Null = 21,
        EnumMember = 22,
        Struct = 23,
        Event = 24,
        Operator = 25,
        TypeParameter = 26,

        pub fn jsonStringify(
            value: Kind,
            options: json.StringifyOptions,
            out_stream: anytype,
        ) !void {
            try json.stringify(@enumToInt(value), options, out_stream);
        }
    };

    name: []const u8,
    detail: ?[]const u8 = null,
    kind: Kind,
    deprecated: bool = false,
    range: Range,
    selectionRange: Range,
    children: []const DocumentSymbol = &[_]DocumentSymbol{},
};

pub const WorkspaceFolder = struct {
    uri: []const u8,
    name: []const u8,
};

// Only includes options we set in our initialize result.
const InitializeResult = struct {
    offsetEncoding: []const u8,
    capabilities: struct {
        signatureHelpProvider: struct {
            triggerCharacters: []const []const u8,
        },
        textDocumentSync: enum {
            None = 0,
            Full = 1,
            Incremental = 2,

            pub fn jsonStringify(
                value: @This(),
                options: json.StringifyOptions,
                out_stream: anytype,
            ) !void {
                try json.stringify(@enumToInt(value), options, out_stream);
            }
        },
        renameProvider: bool,
        completionProvider: struct {
            resolveProvider: bool,
            triggerCharacters: []const []const u8,
        },
        documentHighlightProvider: bool,
        hoverProvider: bool,
        codeActionProvider: bool,
        declarationProvider: bool,
        definitionProvider: bool,
        typeDefinitionProvider: bool,
        implementationProvider: bool,
        referencesProvider: bool,
        documentSymbolProvider: bool,
        colorProvider: bool,
        documentFormattingProvider: bool,
        documentRangeFormattingProvider: bool,
        foldingRangeProvider: bool,
        selectionRangeProvider: bool,
        workspaceSymbolProvider: bool,
        rangeProvider: bool,
        documentProvider: bool,
        workspace: struct {
            workspaceFolders: struct {
                supported: bool,
                changeNotifications: bool,
            },
        },
        semanticTokensProvider: struct {
            full: bool,
            range: bool,
            legend: struct {
                tokenTypes: []const []const u8,
                tokenModifiers: []const []const u8,
            },
        },
    },
    serverInfo: struct {
        name: []const u8,
        version: ?[]const u8 = null,
    },
};