@@ -2,6 +2,7 @@ using GLib;
 using Gtk;
 using Gee;
 using Singularity;
+using Singularity.Widgets;
 using Peas;
 
 [ModuleInit]
@@ -61,9 +62,41 @@ namespace WallpapersBing {
     }
 }
 
+// Bing market row: 2-letter market code, UI display label, and region
+// bucket ("Americas" / "Europe" / "Asia-Pacific") used as the label
+// prefix in the settings SelectionRow's option list. Plain GLib.Object
+// rather than a struct so it can be stored in a Gee.ArrayList (Vala
+// disallows array types as generic type arguments).
+private class BingMarketEntry : GLib.Object {
+    public string code { get; set; }
+    public string label { get; set; }
+    public string region { get; set; }
+}
+
 public class WallpapersBingPlugin : Object, Singularity.Plugin {
     private PluginContext context;
     private WallpapersBing.Provider? provider;
+    private const string BING_MARKETS_ID_ALL = "all";
+    // 13 markets, grouped by region. Order matches the comment block in
+    // cix-installer/post-install/45-wallpaper-rotator.sh's
+    // ncz-wallpaper-bing (Americas, Europe, Asia-Pacific).
+    // [0] = market code, [1] = display label, [2] = region header.
+    private const string BING_MARKETS_TABLE = "en-US\tUnited States\tAmericas"
+        + "|en-CA\tCanada English\tAmericas"
+        + "|fr-CA\tCanada French\tAmericas"
+        + "|pt-BR\tBrazil\tAmericas"
+        + "|en-GB\tUnited Kingdom\tEurope"
+        + "|fr-FR\tFrance\tEurope"
+        + "|de-DE\tGermany\tEurope"
+        + "|es-ES\tSpain\tEurope"
+        + "|it-IT\tItaly\tEurope"
+        + "|en-IN\tIndia\tAsia-Pacific"
+        + "|ja-JP\tJapan\tAsia-Pacific"
+        + "|zh-CN\tChina\tAsia-Pacific"
+        + "|ko-KR\tSouth Korea\tAsia-Pacific";
+    private Gee.ArrayList<BingMarketEntry> bing_markets_rows = new Gee.ArrayList<BingMarketEntry>();
+    private SelectionRow? bing_markets_row = null;
+    private bool bing_markets_updating = false;
 
     public void activate(PluginContext ctx) {
         this.context = ctx;
@@ -84,6 +117,171 @@ public class WallpapersBingPlugin : Object, Singularity.Plugin {
         lbl.wrap = true;
         lbl.xalign = 0;
         box.append(lbl);
+
+        // Preferred-region selector. Every market is always fetched and
+        // combined by the ncz-wallpaper-bing helper; this only sets which
+        // region's copy of a duplicate photo wins the caption/credit when
+        // the same photo is shared across regions -- see
+        // ~/.config/ncz-wallpaper/bing-markets, which
+        // 45-wallpaper-rotator.sh's ncz-wallpaper-bing reads verbatim.
+        // A single inline SelectionRow (not a popup dialog): "All
+        // Markets, No Preference" first, then all 13 markets from
+        // BING_MARKETS_TABLE labelled "<Region> - <Market>" so the region
+        // grouping survives as label text without section headers.
+        init_bing_markets_table();
+        var bing_markets_options = new Gee.ArrayList<Singularity.Core.AppSettingOption>();
+        bing_markets_options.add(new Singularity.Core.AppSettingOption() { id = BING_MARKETS_ID_ALL, label = _("All Markets, No Preference") });
+        foreach (var market in bing_markets_rows) {
+            bing_markets_options.add(new Singularity.Core.AppSettingOption() {
+                id = market.code, label = "%s - %s".printf(market.region, market.label) });
+        }
+        // Initial selection reflects the file: "all" or absent = All
+        // Markets; otherwise the first configured market code (a
+        // preference is singular). Falls back to "all" if the file names
+        // a code that isn't in the current table, so the row always
+        // opens on a real entry.
+        string bing_markets_current = BING_MARKETS_ID_ALL;
+        if (!bing_markets_file_is_all()) {
+            string[] configured = bing_markets_read_codes();
+            if (configured.length > 0) {
+                foreach (var opt in bing_markets_options) {
+                    if (opt.id == configured[0]) { bing_markets_current = configured[0]; break; }
+                }
+            }
+        }
+        bing_markets_row = new SelectionRow.with_options(_("Bing Preferred Region"), bing_markets_options,
+            bing_markets_current);
+        bing_markets_row.subtitle = _("Bing always combines every region's photo of the day; this only picks whose caption and credit win when the same photo is shared");
+        bing_markets_row.selected.connect((id) => {
+            if (bing_markets_updating || bing_markets_row == null) return;
+            if (id == BING_MARKETS_ID_ALL) {
+                write_bing_markets_all();
+            } else {
+                write_bing_markets_codes({id});
+            }
+        });
+        box.append(bing_markets_row);
         return box;
     }
+
+    // Lower-case an ASCII string. Vala's GLib string has no public
+    // lowercase() (only casefold(), which is Unicode-aware and therefore
+    // locale-sensitive -- the bing-market codes are all ISO 639-1 +
+    // ISO 3166-1 letters, so a literal ASCII fold is both correct and
+    // cheaper).
+    private static string ascii_lower(string s) {
+        string out = "";
+        for (int i = 0; i < s.length; i++) {
+            char c = s[i];
+            if (c >= 'A' && c <= 'Z') c = (char)(c + 32);
+            out += c.to_string();
+        }
+        return out;
+    }
+
+    // Parse BING_MARKETS_TABLE into bing_markets_rows ({code, label,
+    // region}), in table order. Called once per get_settings_widget()
+    // build, before the SelectionRow option list is built from it.
+    private void init_bing_markets_table() {
+        bing_markets_rows.clear();
+        foreach (string entry in BING_MARKETS_TABLE.split("|")) {
+            string[] cols = entry.split("\t");
+            if (cols.length != 3) continue;
+            var row = new BingMarketEntry() { code = cols[0], label = cols[1], region = cols[2] };
+            bing_markets_rows.add(row);
+        }
+    }
+
+    // Full path to the bing-markets file the cix-installer rotator
+    // already reads. Lives under XDG_CONFIG_HOME so it tracks the user
+    // even when $HOME is relocated for test sessions.
+    private string bing_markets_file_path() {
+        return GLib.Path.build_filename(
+            GLib.Environment.get_user_config_dir(),
+            "ncz-wallpaper",
+            "bing-markets");
+    }
+
+    // Read the bing-markets file and report whether its content
+    // (trimmed, lowercased) is the "all" sentinel -- i.e. "no preferred
+    // region". Absent file also returns true so the SelectionRow starts
+    // on "All Markets, No Preference" on a fresh install, matching the
+    // rotator's own default (preferred_market() in
+    // 45-wallpaper-rotator.sh returns None for an absent file too).
+    private bool bing_markets_file_is_all() {
+        string path = bing_markets_file_path();
+        if (!FileUtils.test(path, FileTest.EXISTS)) return true;
+        string text;
+        try {
+            FileUtils.get_contents(path, out text);
+        } catch (Error e) {
+            return true;
+        }
+        return ascii_lower(text.strip()) == "all";
+    }
+
+    // Read the bing-markets file and return the configured codes as an
+    // array. "all" (any case) or absent -> empty list. Otherwise split
+    // on any of whitespace/comma and keep tokens matching the
+    // 2-letter-2-letter market pattern, preserving file order. Only the
+    // FIRST entry is ever honoured as the preference, but every matched
+    // token is returned so a legacy multi-market file degrades to "the
+    // first one wins" rather than silently losing the whole value.
+    private string[] bing_markets_read_codes() {
+        string path = bing_markets_file_path();
+        if (!FileUtils.test(path, FileTest.EXISTS)) return {};
+        string text;
+        try {
+            FileUtils.get_contents(path, out text);
+        } catch (Error e) {
+            return {};
+        }
+        if (ascii_lower(text.strip()) == "all") return {};
+        string[] codes = {};
+        string[] seen = {};
+        foreach (string tok in text.strip().split_set(" \t\n,")) {
+            if (tok.length == 0) continue;
+            if (tok.length != 5 || tok[2] != '-') continue;
+            bool dup = false;
+            foreach (string existing in seen) if (existing == tok) { dup = true; break; }
+            if (dup) continue;
+            seen += tok;
+            codes += tok;
+        }
+        return codes;
+    }
+
+    // Atomic write of a single-line contents string to the bing-markets
+    // file, so the daemon (which polls the file) never reads a
+    // half-flushed value. Creates the directory if absent. Silent on
+    // failure -- the daemon's default kicks in if the file is missing.
+    private void write_bing_markets_contents(string contents) {
+        string path = bing_markets_file_path();
+        string dir = GLib.Path.get_dirname(path);
+        try {
+            GLib.DirUtils.create_with_parents(dir, 0700);
+            string tmp = path + ".tmp";
+            FileUtils.set_contents(tmp, contents);
+            if (FileUtils.rename(tmp, path) != 0) {
+                warning("bing markets: could not rename %s into place", path);
+            }
+        } catch (Error e) {
+            warning("bing markets: could not write %s: %s", path, e.message);
+        }
+    }
+
+    private void write_bing_markets_all() {
+        write_bing_markets_contents("all\n");
+    }
+
+    // Write the chosen preferred market as a single line. Empty list ->
+    // fall back to "all" rather than an empty file, making the user's
+    // "no preferred region" intent explicit on disk.
+    private void write_bing_markets_codes(string[] codes) {
+        if (codes.length == 0) {
+            write_bing_markets_all();
+            return;
+        }
+        write_bing_markets_contents(string.joinv(" ", codes) + "\n");
+    }
 }