# Stylix — themes the long tail of applications (GTK, Qt, cursors,
# fonts) from the same state.json that drives the live engine.
#
# Division of labour: the hot-reload trio (Hyprland, Waybar, Kitty)
# is owned by the Nomarchy engine and updates instantly; everything
# Stylix touches updates on the next home-manager switch. That is why
# autoEnable is off and the trio's Stylix targets stay disabled.
#
# Note: the stylix home module itself is imported by homeModules.nomarchy
# in flake.nix (it needs the stylix flake input).
{ config, lib, pkgs, ... }:

let
  cfg = config.nomarchy;
  t = cfg.theme;
  c = t.colors;
  hex = lib.removePrefix "#";

  # Accent-button chips (#130). The label is the palette's base — dark on a
  # dark theme, cream on a light one — so the chip has to be pulled AWAY from
  # the label until the label is legible: toward white when the label is dark,
  # toward black when it is cream. Same factor both ways; only the anchor
  # flips, so "solid accent button, base label" stays the design and just
  # shifts tone.
  #
  # Why a nudge at all: on a saturated mid-tone accent NOTHING clears 4.5 —
  # neither the cream base (summer-day: 2.72) nor the dark text (1.65) — which
  # is why upstream adw-gtk3 ships white-on-accent at ~2.7 and why "darken the
  # label" was a dead end. The chip must move.
  #
  # 0.70 measured across all 24 palettes (tools/check-theme-contrast.py asserts
  # it): worst dark 4.86 (nord/bad), worst light 5.59 (summer-day). Today's 0.90
  # fails seven themes — miasma/bad 3.43, rose-pine 2.70 — so this is not only a
  # light-theme fix, which is what the item assumed.
  #
  # GTK's mix(a, b, f) = a + (b - a) * f (gtkcsscolorvalue.c), i.e. f is the
  # weight of the SECOND colour: 0.70 = 70% accent, 30% anchor. Read it that way
  # or the ladder below looks inverted.
  chipAnchor = if t.mode == "light" then "black" else "white";
  # Each state pulls further from the label, so contrast only ever improves —
  # rest is the worst case and the one the check pins.
  chip = role: f: "mix(${chipAnchor}, ${role}, ${f})";

  # Map the Nomarchy palette onto base16 roles.
  base16 = {
    base00 = hex c.base;     # default background
    base01 = hex c.mantle;   # darker background (status bars)
    base02 = hex c.surface;  # selection background
    base03 = hex c.muted;    # comments
    base04 = hex c.subtext;  # dark foreground
    base05 = hex c.text;     # default foreground
    base06 = hex c.text;     # light foreground
    base07 = hex c.text;     # lightest foreground
    base08 = hex c.bad;      # red
    base09 = hex c.warn;     # orange
    base0A = hex c.warn;     # yellow
    base0B = hex c.good;     # green
    base0C = hex (builtins.elemAt t.ansi 6); # cyan
    base0D = hex c.accent;   # blue
    base0E = hex c.accentAlt;# magenta
    base0F = hex c.bad;      # brown/deprecated
  };

in
{
  config = lib.mkIf cfg.stylix.enable {
    stylix = {
      enable = true;
      autoEnable = false; # explicit targets only — the engine owns the rest
      polarity = if t.mode == "light" then "light" else "dark";
      base16Scheme = base16;

      targets = {
        gtk = {
          enable = true;
          # nm-applet / classic GTK menus: Stylix base16 selection can
          # collapse into surface/muted on dark themes (Boreal: selected
          # row and submenu arrows were effectively invisible). High-
          # contrast selected rows + explicit arrow colour. Appended to
          # Stylix's generated gtk.css (not gtk.gtk3.extraCss — that is a
          # no-op under Stylix).
          #
          # #98: dialog button labels. Stylix always installs theme name
          # "adw-gtk3" (light sheet) and only recolors @define-color vars.
          # The light sheet hardcodes dark/black button text in places; on a
          # dark palette that becomes black-on-dark in GTK dialogs. We force
          # adw-gtk3-dark for dark mode (below) and still pin button label
          # colours here so dialogs stay legible if a light sheet slips in.
          extraCss = ''
            menu menuitem, .menu menuitem, .context-menu menuitem {
              color: #${base16.base05};
            }
            menu menuitem:hover, menu menuitem:selected,
            .menu menuitem:hover, .menu menuitem:selected,
            .context-menu menuitem:hover, .context-menu menuitem:selected,
            menubar > menuitem:hover {
              background-color: #${base16.base0D};
              color: #${base16.base00};
            }
            menu menuitem:disabled, .menu menuitem:disabled {
              color: #${base16.base03};
            }
            /* Submenu disclosure arrows need no icon remap: pan-end-symbolic
               resolves via Papirus-Dark's breeze-dark inheritance. The
               "invisible arrow" bug was Waybar's process-wide stylesheet:
               its `* { min-height: 0; }` reset also hits the SNI tray menus
               Waybar hosts and collapses arrow/check nodes. NB: this file
               CANNOT fix that — Waybar adds its provider at USER priority
               too and wins the tie in practice (GTK 3.24, observed), so
               every waybar.css carries its own menu counter-rules. The
               rules here cover menus in ordinary GTK apps only. */
            menu menuitem arrow, .menu menuitem arrow, .context-menu menuitem arrow {
              min-width: 16px;
              min-height: 16px;
            }
            check, radio {
              min-width: 14px;
              min-height: 14px;
              color: inherit;
            }
            /* GTK4 / popover menus (some portals). */
            popover.menu contents modelbutton {
              color: #${base16.base05};
            }
            popover.menu contents modelbutton:hover,
            popover.menu contents modelbutton:selected {
              background-color: #${base16.base0D};
              color: #${base16.base00};
            }

            /* Dialog / message-box action buttons (#98). */
            button, button label,
            .dialog-action-area button,
            .dialog-action-area button label,
            messagedialog button,
            messagedialog button label,
            .message-dialog button,
            .message-dialog button label {
              color: #${base16.base05};
            }
            button:disabled, button:disabled label {
              color: alpha(#${base16.base05}, 0.5);
            }
            /* Accent buttons: the palette's base as the label, on a chip
               pulled away from it (#130 — see `chip` above for the why and
               the measured numbers).

               BOTH chips are pinned, not just destructive as in #98. Two
               reasons, and the second is the durable one:
                 1. adw-gtk3 builds the destructive background from
                    currentColor — mix(@destructive_color,
                    alpha(currentColor,…)) — so pinning the label alone drags
                    the background with it and the button renders dark-on-dark
                    (1.03:1, invisible). That is the #98 bug.
                 2. A pinned label on an UNPINNED background is unknowable:
                    no static check can see what it renders on, which is
                    exactly why every check was green while #98 shipped. A
                    pinned pair is arithmetic, and
                    tools/check-theme-contrast.py now asserts it for all 24
                    palettes. The rule for anything added here: pin the pair,
                    or pin neither.

               Enabled only — :disabled keeps the sheet's own chrome and
               already renders legibly. .default is GTK's dialog default and
               adw-gtk3 styles it as an accent button, which is why it shares
               the suggested chip rather than inheriting a plain one. */
            button.suggested-action, button.suggested-action label,
            button.destructive-action, button.destructive-action label,
            button.default, button.default label {
              color: #${base16.base00};
            }
            button.suggested-action:not(.flat):not(:disabled),
            button.default:not(.flat):not(:disabled) {
              background-color: ${chip "@accent_bg_color" "0.70"};
            }
            button.suggested-action:not(.flat):not(:disabled):hover,
            button.default:not(.flat):not(:disabled):hover {
              background-color: ${chip "@accent_bg_color" "0.65"};
            }
            button.suggested-action:not(.flat):not(:disabled):active,
            button.suggested-action:not(.flat):not(:disabled):checked,
            button.default:not(.flat):not(:disabled):active,
            button.default:not(.flat):not(:disabled):checked {
              background-color: ${chip "@accent_bg_color" "0.55"};
            }
            button.destructive-action:not(.flat):not(:disabled) {
              background-color: ${chip "@destructive_bg_color" "0.70"};
            }
            button.destructive-action:not(.flat):not(:disabled):hover {
              background-color: ${chip "@destructive_bg_color" "0.65"};
            }
            button.destructive-action:not(.flat):not(:disabled):active,
            button.destructive-action:not(.flat):not(:disabled):checked {
              background-color: ${chip "@destructive_bg_color" "0.55"};
            }
            button.suggested-action.flat, button.suggested-action.flat label {
              color: #${base16.base0D};
            }
            button.destructive-action.flat, button.destructive-action.flat label {
              color: #${base16.base08};
            }
          '';
        };
        qt.enable = true;
        # No-op unless programs.zathura is on (viewers.nix enables it).
        zathura.enable = true;
      };

      cursor = {
        name = lib.mkDefault "Bibata-Modern-Classic";
        package = lib.mkDefault pkgs.bibata-cursors;
        size = lib.mkDefault 24;
      };

      # GTK/file-manager/rofi icon theme, resolved from the JSON in
      # theme.nix (per-theme `icons`, else Papirus-Dark/Light by mode).
      # Stylix sets gtk.iconTheme from this; both dark/light point at the
      # already-mode-resolved name. The package is papirus by default and
      # only unions in another pack when a theme's `icons` names one
      # (theme.nix — opt-in, no default closure bloat).
      icons = {
        enable = true;
        package = lib.mkDefault t.iconThemePackage;
        dark = t.iconTheme;
        light = t.iconTheme;
      };

      fonts = {
        monospace = {
          name = t.fonts.mono;
          package = lib.mkDefault pkgs.nerd-fonts.jetbrains-mono;
        };
        sansSerif = {
          name = t.fonts.ui;
          package = lib.mkDefault pkgs.inter;
        };
        serif = {
          name = t.fonts.ui;
          package = lib.mkDefault pkgs.inter;
        };
        emoji = {
          name = "Noto Color Emoji";
          package = lib.mkDefault pkgs.noto-fonts-color-emoji;
        };
        sizes.terminal = t.fonts.size;
      };
    };

    # GTK3 hides menu-item icons by default (gtk-menu-images was flipped
    # off upstream in 3.10). Classic tray menus — nm-applet's Wi-Fi list,
    # udiskie — are built as image menu items, so without this their icons
    # silently vanish. Stylix drives the HM gtk module, so extraConfig
    # merges into the same settings.ini it already writes.
    gtk.gtk3.extraConfig = {
      "gtk-menu-images" = 1;
      # Pair with adw-gtk3-dark so the theme sheet itself is dark, not just
      # the @define-color recolor (see gtk.theme.name below).
      "gtk-application-prefer-dark-theme" = t.mode != "light";
    };
    gtk.gtk4.extraConfig."gtk-application-prefer-dark-theme" = t.mode != "light";

    # #98: Stylix hardcodes gtk.theme.name = "adw-gtk3" (light CSS) for every
    # polarity and only injects libadwaita colour tokens. The light adw-gtk3
    # sheet assumes light chrome and hardcodes near-black button labels in
    # places — on Boreal that is black text on dark dialog buttons. Force
    # the matching dark/light sheet; the package still provides both names.
    gtk.theme = {
      package = lib.mkDefault pkgs.adw-gtk3;
      name = lib.mkForce (if t.mode == "light" then "adw-gtk3" else "adw-gtk3-dark");
    };

    # GTK4/libadwaita and Qt6 apps decide dark vs light from the XDG
    # portal's color-scheme (org.freedesktop.appearance), which
    # xdg-desktop-portal-gtk sources from this gsettings key. Stylix sets
    # the GTK theme and `polarity` but not this, so a light theme still
    # rendered libadwaita/Qt apps dark (and vice-versa). Drive it from the
    # palette mode. (programs.dconf.enable is already on system-side.)
    dconf.settings."org/gnome/desktop/interface" = {
      color-scheme =
        if t.mode == "light" then "prefer-light" else "prefer-dark";
      gtk-theme =
        if t.mode == "light" then "adw-gtk3" else "adw-gtk3-dark";
    };
  };
}