const std = @import("std");
const builtin = @import("builtin");
const vaxis = @import("vaxis");

const linux = @import("linux.zig");
const macos = @import("macos.zig");

const OSVersion = struct {
    name: []const u8,
    major: []u64,
    minor: []u64,
    patch: []u64,
};

const Shell = struct {
    name: []const u8,
    version: []const u8,
};

pub fn get_shell(allocator: std.mem.Allocator) !vaxis.Cell.Segment {
    const shell_env = std.posix.getenv("SHELL") orelse "Unknown";
    var shell_path = std.mem.splitBackwards(u8, shell_env, "/");

    var buf: [64]u8 = undefined;
    const filename = shell_path.first();
    if (std.mem.eql(u8, filename, "zsh")) {
        const zsh_version = try get_zsh_version(allocator, &buf, shell_env);
        // defer allocator.free(zsh_version);

        return .{
            .text = try std.fmt.allocPrint(
                allocator,
                ": {s} {s}\n",
                .{
                    filename,
                    zsh_version,
                },
            ),
        };
    } else if (std.mem.eql(u8, filename, "bash")) {
        const bash_version = try get_bash_version(allocator, &buf, shell_env);

        return .{
            .text = try std.fmt.allocPrint(
                allocator,
                ": bash {s}\n",
                .{bash_version},
            ),
        };
    } else if (std.mem.eql(u8, filename, "bash")) {
        const version = try std.process.Child.run(
            .{
                .allocator = allocator,
                .argv = &.{ shell_env, "--version" },
            },
        );
        defer allocator.free(version.stdout);
        defer allocator.free(version.stderr);

        return .{
            .text = try std.fmt.allocPrint(
                allocator,
                ": {s}\n",
                .{version.stdout},
            ),
        };
    }

    return .{
        .text = try std.fmt.allocPrint(allocator, ": {s}\n", .{shell_env}),
    };
}

pub fn get_kernel_version(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.get_kernel_version(buf),
            };
        },
        else => return .{ .text = try std.fmt.bufPrint(buf, "unknown", .{}) },
    }
}

pub fn get_uptime(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.get_uptime(buf),
            };
        },
        else => return .{ .text = try std.fmt.bufPrint(buf, "unknown", .{}) },
    }
}

pub fn get_cpu_info(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.get_cpu_info(buf),
            };
        },
        else => return .{ .text = try std.fmt.bufPrint(buf, "unknown", .{}) },
    }
}
pub fn get_mem_info(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.get_mem_info(buf),
            };
        },
        else => return .{ .text = try std.fmt.bufPrint(buf, "unknown", .{}) },
    }
}

pub fn get_battery(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.get_battery_info(buf),
            };
        },
        else => return .{ .text = "unknown" },
    }
}

pub fn get_os_version(buf: []u8) !vaxis.Cell.Segment {
    switch (builtin.os.tag) {
        .macos => {
            return .{
                .text = try macos.macos_version(buf),
            };
        },
        .linux => {
            return .{
                .text = try std.fmt.bufPrint(buf, "{s} {s}", .{ try linux.kernel_version(), try linux.distribution() }),
            };
        },
        .freebsd => {
            return .{
                .text = try std.fmt.bufPrint(buf, "not implemented", .{}),
            };
        },
        else => return .{ .text = try std.fmt.bufPrint(buf, "unknown", .{}) },
    }
}

pub fn get_terminal(buf: []u8) !vaxis.Cell.Segment {
    const term_program = std.posix.getenv("TERM_PROGRAM") orelse "Unknown";

    if (std.mem.eql(u8, term_program, "ghostty")) {
        return .{
            .text = try std.fmt.bufPrint(buf, ": {s} 󰊠\n", .{term_program}),
        };
    }

    return .{
        .text = try std.fmt.bufPrint(buf, ": {s}\n", .{term_program}),
    };
}

fn get_zsh_version(allocator: std.mem.Allocator, buf: []u8, zsh_path: []const u8) ![]const u8 {
    const zsh_version = try std.fmt.bufPrint(buf, "Unknown", .{});
    const version_string = std.process.Child.run(
        .{
            .allocator = allocator,
            .argv = &.{ zsh_path, "--version" },
        },
    ) catch {
        return zsh_version;
    };
    defer allocator.free(version_string.stdout);
    defer allocator.free(version_string.stderr);

    var version = std.mem.split(u8, version_string.stdout, " ");
    _ = version.first();

    return try std.fmt.bufPrint(buf, "{s}", .{version.next() orelse "Uknown"});
    // return try std.fmt.allocPrint(allocator, "{s}", .{version.next() orelse "Unknown"});
}
fn get_bash_version(allocator: std.mem.Allocator, buf: []u8, bash_path: []const u8) ![]const u8 {
    const version_string = try std.process.Child.run(
        .{
            .allocator = allocator,
            .argv = &.{ bash_path, "--version" },
        },
    );
    defer allocator.free(version_string.stdout);
    defer allocator.free(version_string.stderr);

    var split_lines = std.mem.split(u8, version_string.stdout, "\n");

    var version_line = std.mem.split(u8, split_lines.first(), " ");

    var i: usize = 0;
    while (version_line.next()) |word| {
        std.debug.print("version_line: {s}", .{word});
        if (i == 3) {
            return try std.fmt.bufPrint(buf, "{s}", .{word});
        }
        i += 1;
    }

    return try std.fmt.bufPrint(buf, "Unknown", .{});
}

pub fn get_user(buf: []u8) ![]const u8 {
    const user = std.posix.getenv("USER") orelse "Unknown";

    return try std.fmt.bufPrint(buf, "{s}", .{user});
}

pub fn get_hostname(buf: *[std.posix.HOST_NAME_MAX]u8) ![]const u8 {
    const hostname = try std.posix.gethostname(&buf);

    return try std.fmt.bufPrint(buf, hostname, .{});
}

test "get_bash_version" {
    var buf: [8]u8 = undefined;
    const bash_version = try get_bash_version(std.testing.allocator, &buf, "/run/current-system/sw/bin/bash");

    try std.testing.expectEqualSlices(u8, "5.2.32(1)-release", bash_version);
}