const std = @import("std");
const Allocator = std.mem.Allocator;
const tp = @import("thespian");
const tracy = @import("tracy");
const EventHandler = @import("EventHandler");
const Plane = @import("renderer").Plane;

const Widget = @import("../Widget.zig");
const ed = @import("../editor.zig");

plane: Plane,
matches: usize = 0,
cursels: usize = 0,
selection: ?ed.Selection = null,
buf: [256]u8 = undefined,
rendered: [:0]const u8 = "",
on_event: ?EventHandler,

const Self = @This();

pub fn create(allocator: Allocator, parent: Plane, event_handler: ?EventHandler) @import("widget.zig").CreateError!Widget {
    const self: *Self = try allocator.create(Self);
    self.* = .{
        .plane = try Plane.init(&(Widget.Box{}).opts(@typeName(Self)), parent),
        .on_event = event_handler,
    };
    return Widget.to(self);
}

pub fn deinit(self: *Self, allocator: Allocator) void {
    self.plane.deinit();
    allocator.destroy(self);
}

pub fn layout(self: *Self) Widget.Layout {
    return .{ .static = self.rendered.len };
}

pub fn render(self: *Self, theme: *const Widget.Theme) bool {
    const frame = tracy.initZone(@src(), .{ .name = @typeName(@This()) ++ " render" });
    defer frame.deinit();
    self.plane.set_base_style(theme.statusbar);
    self.plane.erase();
    self.plane.home();
    _ = self.plane.putstr(self.rendered) catch {};
    return false;
}

fn format(self: *Self) void {
    var fbs = std.io.fixedBufferStream(&self.buf);
    const writer = fbs.writer();
    _ = writer.write(" ") catch {};
    if (self.matches > 1) {
        std.fmt.format(writer, "({d} matches)", .{self.matches}) catch {};
        if (self.selection) |_|
            _ = writer.write(" ") catch {};
    }
    if (self.cursels > 1) {
        std.fmt.format(writer, "({d} cursors)", .{self.cursels}) catch {};
        if (self.selection) |_|
            _ = writer.write(" ") catch {};
    }
    if (self.selection) |sel_| {
        var sel = sel_;
        sel.normalize();
        const lines = sel.end.row - sel.begin.row;
        if (lines == 0) {
            std.fmt.format(writer, "({d} selected)", .{sel.end.col - sel.begin.col}) catch {};
        } else {
            std.fmt.format(writer, "({d} lines selected)", .{if (sel.end.col == 0) lines else lines + 1}) catch {};
        }
    }
    _ = writer.write(" ") catch {};
    self.rendered = @ptrCast(fbs.getWritten());
    self.buf[self.rendered.len] = 0;
}

pub fn receive(self: *Self, from: tp.pid_ref, m: tp.message) error{Exit}!bool {
    var btn: u32 = 0;
    if (try m.match(.{ "D", tp.any, tp.extract(&btn), tp.more })) {
        if (self.on_event) |h| h.send(from, m) catch {};
        return true;
    }
    if (try m.match(.{ "E", "match", tp.extract(&self.matches) }))
        self.format();
    if (try m.match(.{ "E", "cursels", tp.extract(&self.cursels) }))
        self.format();
    if (try m.match(.{ "E", "close" })) {
        self.matches = 0;
        self.selection = null;
        self.format();
    } else if (try m.match(.{ "E", "sel", tp.more })) {
        var sel: ed.Selection = undefined;
        if (try m.match(.{ tp.any, tp.any, "none" })) {
            self.matches = 0;
            self.selection = null;
        } else if (try m.match(.{ tp.any, tp.any, tp.extract(&sel.begin.row), tp.extract(&sel.begin.col), tp.extract(&sel.end.row), tp.extract(&sel.end.col) })) {
            self.selection = sel;
        }
        self.format();
    }
    return false;
}