const std = @import("std");
const Io = std.Io;

// ── Color Constants ──────────────────────────────────────────────────────────

pub const Color = struct {
    pub const reset = "\x1b[0m";
    pub const bold = "\x1b[1m";
    pub const dim = "\x1b[2m";
    pub const italic = "\x1b[3m";
    pub const underline = "\x1b[4m";

    // Foreground
    pub const red = "\x1b[31m";
    pub const green = "\x1b[32m";
    pub const yellow = "\x1b[33m";
    pub const blue = "\x1b[34m";
    pub const magenta = "\x1b[35m";
    pub const cyan = "\x1b[36m";
    pub const white = "\x1b[37m";
    pub const gray = "\x1b[90m";

    // Bold foreground
    pub const bold_red = "\x1b[1;31m";
    pub const bold_green = "\x1b[1;32m";
    pub const bold_yellow = "\x1b[1;33m";
    pub const bold_blue = "\x1b[1;34m";
    pub const bold_magenta = "\x1b[1;35m";
    pub const bold_cyan = "\x1b[1;36m";
    pub const bold_white = "\x1b[1;37m";
};

// ── Icons ────────────────────────────────────────────────────────────────────

pub const Icon = struct {
    pub const check = "✓";
    pub const cross = "✗";
    pub const bullet = "●";
    pub const circle = "○";
    pub const active = "◉";
    pub const arrow = "→";
    pub const warn = "!";
    pub const lock = "🔒";
    pub const available = "✅";
    pub const star = "★";
};

// ── Color Detection ──────────────────────────────────────────────────────────

pub fn shouldColor() bool {
    // Check NO_COLOR env var (https://no-color.org/)
    if (std.c.getenv("NO_COLOR")) |_| return false;

    // Note: --color=never flag is checked via args in each CLI command
    // since std.process.args() is not available in Zig 0.17
    return true;
}

pub fn shouldColorFromArgs(args: []const []const u8) bool {
    if (std.c.getenv("NO_COLOR")) |_| return false;
    for (args) |arg| {
        if (std.mem.eql(u8, arg, "--color=never")) return false;
    }
    return true;
}

fn c(color: []const u8) []const u8 {
    return if (shouldColor()) color else "";
}

// ── Stderr Output ────────────────────────────────────────────────────────────

pub fn err(io: Io, msg: []const u8) !void {
    const w = Io.File.stderr();
    try w.writeStreamingAll(io, c(Color.red));
    try w.writeStreamingAll(io, "error: ");
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, msg);
    try w.writeStreamingAll(io, "\n");
}

pub fn errWithHint(io: Io, msg: []const u8, hint: []const u8) !void {
    const w = Io.File.stderr();
    try w.writeStreamingAll(io, c(Color.red));
    try w.writeStreamingAll(io, "error: ");
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, msg);
    try w.writeStreamingAll(io, "\n");
    try w.writeStreamingAll(io, c(Color.dim));
    try w.writeStreamingAll(io, "  hint: ");
    try w.writeStreamingAll(io, hint);
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, "\n");
}

pub fn warn(io: Io, msg: []const u8) !void {
    const w = Io.File.stderr();
    try w.writeStreamingAll(io, c(Color.yellow));
    try w.writeStreamingAll(io, "warn: ");
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, msg);
    try w.writeStreamingAll(io, "\n");
}

// ── Success Output ───────────────────────────────────────────────────────────

pub fn success(io: Io, msg: []const u8) !void {
    const w = Io.File.stdout();
    try w.writeStreamingAll(io, c(Color.green));
    try w.writeStreamingAll(io, Icon.check);
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, " ");
    try w.writeStreamingAll(io, msg);
    try w.writeStreamingAll(io, "\n");
}

pub fn successDim(io: Io, msg: []const u8, dim_text: []const u8) !void {
    const w = Io.File.stdout();
    try w.writeStreamingAll(io, c(Color.green));
    try w.writeStreamingAll(io, Icon.check);
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, " ");
    try w.writeStreamingAll(io, msg);
    try w.writeStreamingAll(io, c(Color.dim));
    try w.writeStreamingAll(io, dim_text);
    try w.writeStreamingAll(io, c(Color.reset));
    try w.writeStreamingAll(io, "\n");
}

// ── Formatting Helpers ───────────────────────────────────────────────────────

pub fn writeStyled(writer: anytype, io: Io, label: []const u8, value: []const u8, color: []const u8) !void {
    try writer.writeStreamingAll(io, c(Color.dim));
    try writer.writeStreamingAll(io, label);
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, " ");
    try writer.writeStreamingAll(io, c(color));
    try writer.writeStreamingAll(io, value);
    try writer.writeStreamingAll(io, c(Color.reset));
}

pub fn writeHeader(writer: anytype, io: Io, title: []const u8) !void {
    try writer.writeStreamingAll(io, c(Color.bold));
    try writer.writeStreamingAll(io, title);
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, "\n");
}

pub fn writeSection(writer: anytype, io: Io, title: []const u8) !void {
    try writer.writeStreamingAll(io, "\n");
    try writer.writeStreamingAll(io, c(Color.bold));
    try writer.writeStreamingAll(io, title);
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, "\n");
}

pub fn writeStatusLine(writer: anytype, io: Io, label: []const u8, value: []const u8, color: []const u8) !void {
    try writer.writeStreamingAll(io, "  ");
    try writer.writeStreamingAll(io, c(Color.dim));
    try writer.writeStreamingAll(io, label);
    try writer.writeStreamingAll(io, c(Color.reset));
    if (label.len < 14) {
        const pad = 14 - label.len;
        var i: usize = 0;
        while (i < pad) : (i += 1) {
            try writer.writeStreamingAll(io, " ");
        }
    }
    try writer.writeStreamingAll(io, c(color));
    try writer.writeStreamingAll(io, value);
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, "\n");
}

pub fn writeTableHeader(writer: anytype, io: Io, columns: []const []const u8, widths: []const usize) !void {
    try writer.writeStreamingAll(io, c(Color.dim));
    for (columns, 0..) |col, i| {
        try writer.writeStreamingAll(io, col);
        const pad = widths[i] - col.len;
        var j: usize = 0;
        while (j < pad) : (j += 1) {
            try writer.writeStreamingAll(io, " ");
        }
        if (i < columns.len - 1) try writer.writeStreamingAll(io, "  ");
    }
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, "\n");

    try writer.writeStreamingAll(io, c(Color.dim));
    for (widths) |w| {
        var j: usize = 0;
        while (j < w) : (j += 1) {
            try writer.writeStreamingAll(io, "-");
        }
        try writer.writeStreamingAll(io, "  ");
    }
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, "\n");
}

pub fn writeTableRow(writer: anytype, io: Io, values: []const []const u8, widths: []const usize, colors: []const []const u8) !void {
    for (values, 0..) |val, i| {
        const color = if (i < colors.len) colors[i] else Color.white;
        try writer.writeStreamingAll(io, c(color));
        try writer.writeStreamingAll(io, val);
        try writer.writeStreamingAll(io, c(Color.reset));
        const pad = widths[i] - val.len;
        var j: usize = 0;
        while (j < pad) : (j += 1) {
            try writer.writeStreamingAll(io, " ");
        }
        if (i < values.len - 1) try writer.writeStreamingAll(io, "  ");
    }
    try writer.writeStreamingAll(io, "\n");
}

pub fn writeBadge(writer: anytype, io: Io, text: []const u8, bg_color: []const u8) !void {
    try writer.writeStreamingAll(io, c(bg_color));
    try writer.writeStreamingAll(io, c(Color.bold));
    try writer.writeStreamingAll(io, " ");
    try writer.writeStreamingAll(io, text);
    try writer.writeStreamingAll(io, " ");
    try writer.writeStreamingAll(io, c(Color.reset));
}

pub fn writeKeyValue(writer: anytype, io: Io, key: []const u8, value: []const u8, key_color: []const u8, value_color: []const u8) !void {
    try writer.writeStreamingAll(io, c(key_color));
    try writer.writeStreamingAll(io, key);
    try writer.writeStreamingAll(io, c(Color.reset));
    try writer.writeStreamingAll(io, ": ");
    try writer.writeStreamingAll(io, c(value_color));
    try writer.writeStreamingAll(io, value);
    try writer.writeStreamingAll(io, c(Color.reset));
}

// ── Convenience Wrappers ─────────────────────────────────────────────────────

pub fn boldText(writer: anytype, io: Io, text: []const u8) !void {
    try writer.writeStreamingAll(io, c(Color.bold));
    try writer.writeStreamingAll(io, text);
    try writer.writeStreamingAll(io, c(Color.reset));
}

pub fn dimText(writer: anytype, io: Io, text: []const u8) !void {
    try writer.writeStreamingAll(io, c(Color.dim));
    try writer.writeStreamingAll(io, text);
    try writer.writeStreamingAll(io, c(Color.reset));
}

pub fn coloredText(writer: anytype, io: Io, text: []const u8, color: []const u8) !void {
    try writer.writeStreamingAll(io, c(color));
    try writer.writeStreamingAll(io, text);
    try writer.writeStreamingAll(io, c(Color.reset));
}

test "color constants" {
    try std.testing.expectEqualStrings("\x1b[0m", Color.reset);
    try std.testing.expectEqualStrings("\x1b[1m", Color.bold);
    try std.testing.expectEqualStrings("\x1b[31m", Color.red);
}