From cc12c90dbc3bc7066df0b2a25103f61e4be70749 Mon Sep 17 00:00:00 2001
From: Yorhel <git@yorhel.nl>
Date: Sun, 14 Jul 2024 16:21:59 +0200
Subject: [PATCH] Re-add scan progress UI + directory refreshing

---
 src/browser.zig |   4 +-
 src/delete.zig  |   2 +-
 src/main.zig    |   9 +-
 src/model.zig   | 142 ++++++---------------------
 src/scan.zig    |   9 +-
 src/sink.zig    | 252 +++++++++++++++++++++++++++++++++++++++++++++---
 6 files changed, 284 insertions(+), 134 deletions(-)

diff --git a/src/browser.zig b/src/browser.zig
index e48c916..caef8f4 100644
--- a/src/browser.zig
+++ b/src/browser.zig
@@ -4,7 +4,7 @@
 const std = @import("std");
 const main = @import("main.zig");
 const model = @import("model.zig");
-const scan = @import("scan.zig");
+const sink = @import("sink.zig");
 const delete = @import("delete.zig");
 const ui = @import("ui.zig");
 const c = @cImport(@cInclude("time.h"));
@@ -848,7 +848,7 @@ pub fn keyInput(ch: i32) void {
                 message = "Directory refresh feature disabled."
             else {
                 main.state = .refresh;
-                //scan.setupRefresh(dir_parent);
+                sink.state.out = sink.state.Out{ .mem = dir_parent };
             }
         },
         'b' => {
diff --git a/src/delete.zig b/src/delete.zig
index ae262a8..b2653e0 100644
--- a/src/delete.zig
+++ b/src/delete.zig
@@ -62,7 +62,7 @@ fn deleteItem(dir: std.fs.Dir, path: [:0]const u8, ptr: *align(1) ?*model.Entry)
             return if (e != error.DirNotEmpty or d.sub == null) err(e) else false;
     } else
         dir.deleteFileZ(path) catch |e| return err(e);
-    ptr.*.?.delStats(parent);
+    ptr.*.?.zeroStats(parent);
     ptr.* = ptr.*.?.next;
     return false;
 }
diff --git a/src/main.zig b/src/main.zig
index a592b7d..41fce0a 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -542,7 +542,14 @@ pub fn main() void {
     while (true) {
         switch (state) {
             .refresh => {
-                //scan.scan();
+                var full_path = std.ArrayList(u8).init(allocator);
+                defer full_path.deinit();
+                sink.state.out.mem.?.fmtPath(true, &full_path);
+                scan.scan(util.arrayListBufZ(&full_path)) catch {
+                    sink.state.last_error = allocator.dupeZ(u8, full_path.items) catch unreachable;
+                    sink.state.status = .err;
+                    while (state == .refresh) handleEvent(true, true);
+                };
                 state = .browse;
                 browser.loadDir(null);
             },
diff --git a/src/model.zig b/src/model.zig
index 791e439..2e70db7 100644
--- a/src/model.zig
+++ b/src/model.zig
@@ -9,7 +9,7 @@ const util = @import("util.zig");
 pub const EType = enum(u2) { dir, link, file };
 
 // Type for the Entry.Packed.blocks field. Smaller than a u64 to make room for flags.
-pub const Blocks = u60;
+pub const Blocks = u61;
 
 // Memory layout:
 //      (Ext +) Dir + name
@@ -30,12 +30,6 @@ pub const Entry = extern struct {
     pub const Packed = packed struct(u64) {
         etype: EType,
         isext: bool,
-        // Whether or not this entry's size has been counted in its parents.
-        // Counting of Link entries is deferred until the scan/delete operation has
-        // completed, so for those entries this flag indicates an intention to be
-        // counted.
-        // TODO: Think we can remove this
-        counted: bool = false,
         blocks: Blocks = 0, // 512-byte blocks
     };
 
@@ -108,100 +102,33 @@ pub const Entry = extern struct {
             else false;
     }
 
-    pub fn addStats(self: *Entry, parent: *Dir, nlink: u31) void {
-        if (self.pack.counted) return;
-        self.pack.counted = true;
-
-        // Add link to the inode map, but don't count its size (yet).
-        if (self.link()) |l| {
-            l.parent = parent;
-            var d = inodes.map.getOrPut(l) catch unreachable;
-            if (!d.found_existing) {
-                d.value_ptr.* = .{ .counted = false, .nlink = nlink };
-                inodes.total_blocks +|= self.pack.blocks;
-                l.next = l;
-            } else {
-                inodes.setStats(.{ .key_ptr = d.key_ptr, .value_ptr = d.value_ptr }, false);
-                // If the nlink counts are not consistent, reset to 0 so we calculate with what we have instead.
-                if (d.value_ptr.nlink != nlink)
-                    d.value_ptr.nlink = 0;
-                l.next = d.key_ptr.*.next;
-                d.key_ptr.*.next = l;
-            }
-            inodes.addUncounted(l);
-        }
-
-        var it: ?*Dir = parent;
-        while(it) |p| : (it = p.parent) {
-            if (self.ext()) |e|
-                if (p.entry.ext()) |pe|
-                    if (e.mtime > pe.mtime) { pe.mtime = e.mtime; };
-            p.items +|= 1;
-            if (self.pack.etype != .link) {
-                p.entry.size +|= self.size;
-                p.entry.pack.blocks +|= self.pack.blocks;
-            }
-        }
-    }
-
-    // Opposite of addStats(), but has some limitations:
-    // - If addStats() saturated adding sizes, then the sizes after delStats()
-    //   will be incorrect.
-    // - mtime of parents is not adjusted (but that's a feature, possibly?)
-    //
-    // This function assumes that, for directories, all sub-entries have
-    // already been un-counted.
-    //
-    // When removing a Link, the entry's nlink counter is reset to zero, so
-    // that it will be recalculated based on our view of the tree. This means
-    // that links outside of the scanned directory will not be considered
-    // anymore, meaning that delStats() followed by addStats() with the same
-    // data may cause information to be lost.
-    pub fn delStats(self: *Entry, parent: *Dir) void {
-        if (!self.pack.counted) return;
-        defer self.pack.counted = false; // defer, to make sure inodes.setStats() still sees it as counted.
-
-        if (self.link()) |l| {
-            var d = inodes.map.getEntry(l).?;
-            inodes.setStats(d, false);
-            d.value_ptr.nlink = 0;
-            if (l.next == l) {
-                _ = inodes.map.remove(l);
-                _ = inodes.uncounted.remove(l);
-                inodes.total_blocks -|= self.pack.blocks;
-            } else {
-                if (d.key_ptr.* == l)
-                    d.key_ptr.* = l.next;
-                inodes.addUncounted(l.next);
-                // This is O(n), which in this context has the potential to
-                // slow ncdu down to a crawl. But this function is only called
-                // on refresh/delete operations and even then it's not common
-                // to have very long lists, so this blowing up should be very
-                // rare. This removal can also be deferred to setStats() to
-                // amortize the costs, if necessary.
-                var it = l.next;
-                while (it.next != l) it = it.next;
-                it.next = l.next;
-            }
-        }
-
-        var it: ?*Dir = parent;
-        while(it) |p| : (it = p.parent) {
-            p.items -|= 1;
-            if (self.pack.etype != .link) {
-                p.entry.size -|= self.size;
-                p.entry.pack.blocks -|= self.pack.blocks;
-            }
-        }
-    }
-
-    pub fn delStatsRec(self: *Entry, parent: *Dir) void {
+    fn zeroStatsRec(self: *Entry) void {
+        self.pack.blocks = 0;
+        self.size = 0;
+        if (self.file()) |f| f.pack = .{};
         if (self.dir()) |d| {
+            d.items = 0;
+            d.pack.err = false;
+            d.pack.suberr = false;
             var it = d.sub;
-            while (it) |e| : (it = e.next)
-                e.delStatsRec(d);
+            while (it) |e| : (it = e.next) zeroStatsRec(e);
         }
-        self.delStats(parent);
+    }
+
+    // Recursively set stats and those of sub-items to zero and removes counts
+    // from parent directories; as if this item does not exist in the tree.
+    // XXX: Does not update the 'suberr' flag of parent directories, make sure
+    // to call updateSubErr() afterwards.
+    pub fn zeroStats(self: *Entry, parent: ?*Dir) void {
+        // TODO: Uncount nested links.
+
+        var it = parent;
+        while (it) |p| : (it = p.parent) {
+            p.entry.pack.blocks -|= self.pack.blocks;
+            p.entry.size -|= self.size;
+            p.items -|= 1 + (if (self.dir()) |d| d.items else 0);
+        }
+        self.zeroStatsRec();
     }
 };
 
@@ -341,11 +268,6 @@ pub const inodes = struct {
     const Map = std.HashMap(*Link, Inode, HashContext, 80);
     pub var map = Map.init(main.allocator);
 
-    // Cumulative size of all unique hard links in the map.  This is a somewhat
-    // ugly workaround to provide accurate sizes during the initial scan, when
-    // the hard links are not counted as part of the parent directories yet.
-    pub var total_blocks: Blocks = 0;
-
     // List of nodes in 'map' with !counted, to speed up addAllStats().
     // If this list grows large relative to the number of nodes in 'map', then
     // this list is cleared and uncounted_full is set instead, so that
@@ -399,14 +321,12 @@ pub const inodes = struct {
         defer dirs.deinit();
         var it = entry.key_ptr.*;
         while (true) {
-            if (it.entry.pack.counted) {
-                nlink += 1;
-                var parent: ?*Dir = it.parent;
-                while (parent) |p| : (parent = p.parent) {
-                    const de = dirs.getOrPut(p) catch unreachable;
-                    if (de.found_existing) de.value_ptr.* += 1
-                    else de.value_ptr.* = 1;
-                }
+            nlink += 1;
+            var parent: ?*Dir = it.parent;
+            while (parent) |p| : (parent = p.parent) {
+                const de = dirs.getOrPut(p) catch unreachable;
+                if (de.found_existing) de.value_ptr.* += 1
+                else de.value_ptr.* = 1;
             }
             it = it.next;
             if (it == entry.key_ptr.*)
diff --git a/src/scan.zig b/src/scan.zig
index 286bd09..8f13b7d 100644
--- a/src/scan.zig
+++ b/src/scan.zig
@@ -282,13 +282,12 @@ const Thread = struct {
 
 
 pub fn scan(path: [:0]const u8) !void {
+    const sink_threads = sink.createThreads(main.config.threads);
+    defer sink.done();
+
     const stat = try statAt(std.fs.cwd(), path, true);
     const fd = try std.fs.cwd().openDirZ(path, .{ .iterate = true });
 
-    sink.state.threads = main.allocator.alloc(sink.Thread, main.config.threads) catch unreachable;
-    for (sink.state.threads) |*t| t.* = .{};
-    defer main.allocator.free(sink.state.threads);
-
     var state = State{
         .threads = main.allocator.alloc(Thread, main.config.threads) catch unreachable,
     };
@@ -298,7 +297,7 @@ pub fn scan(path: [:0]const u8) !void {
     const dir = Dir.create(fd, stat.dev, exclude.getPatterns(path), root);
     _ = state.tryPush(dir);
 
-    for (sink.state.threads, state.threads, 0..) |*s, *t, n|
+    for (sink_threads, state.threads, 0..) |*s, *t, n|
         t.* = .{ .sink = s, .state = &state, .thread_num = n };
 
     // XXX: Continue with fewer threads on error?
diff --git a/src/sink.zig b/src/sink.zig
index bae419f..cfa5775 100644
--- a/src/sink.zig
+++ b/src/sink.zig
@@ -220,6 +220,14 @@ pub const Dir = struct {
         switch (d.out) {
             .mem => |*m| m.addSpecial(t.arena.allocator(), name, sp),
         }
+        if (sp == .err) {
+            state.last_error_lock.lock();
+            defer state.last_error_lock.unlock();
+            if (state.last_error) |p| main.allocator.free(p);
+            const p = d.path();
+            state.last_error = std.fs.path.joinZ(main.allocator, &.{ p, name }) catch unreachable;
+            main.allocator.free(p);
+        }
     }
 
     pub fn addStat(d: *Dir, t: *Thread, name: []const u8, stat: *const Stat) void {
@@ -255,7 +263,7 @@ pub const Dir = struct {
         }
     }
 
-    fn path(d: *Dir) []const u8 {
+    fn path(d: *Dir) [:0]const u8 {
         var components = std.ArrayList([]const u8).init(main.allocator);
         defer components.deinit();
         var it: ?*Dir = d;
@@ -269,7 +277,7 @@ pub const Dir = struct {
             if (i == 0) break;
             i -= 1;
         }
-        return out.toOwnedSlice() catch unreachable;
+        return out.toOwnedSliceSentinel(0) catch unreachable;
     }
 
     fn ref(d: *Dir) void {
@@ -308,47 +316,263 @@ pub const Thread = struct {
 
 
 pub const state = struct {
+    pub var status: enum { done, err, zeroing, hlcnt, running } = .running;
     pub var threads: []Thread = undefined;
+    pub var out: Out = .{ .mem = null };
+
+    pub var last_error: ?[:0]u8 = null;
+    var last_error_lock = std.Thread.Mutex{};
+    var need_confirm_quit = false;
+
+    pub const Out = union(enum) {
+        mem: ?*model.Dir,
+    };
 };
 
 
+// Must be the first thing to call from a source; initializes global state.
+pub fn createThreads(num: usize) []Thread {
+    state.status = .running;
+    if (state.last_error) |p| main.allocator.free(p);
+    state.last_error = null;
+    state.threads = main.allocator.alloc(Thread, num) catch unreachable;
+    for (state.threads) |*t| t.* = .{};
+    return state.threads;
+}
+
+
+// Must be the last thing to call from a source.
+pub fn done() void {
+    // TODO: Do hardlink stuff.
+    state.status = .done;
+    main.allocator.free(state.threads);
+    // Clear the screen when done.
+    if (main.config.scan_ui == .line) main.handleEvent(false, true);
+}
+
+
 pub fn createRoot(path: []const u8, stat: *const Stat) *Dir {
-    // TODO: Handle other outputs
-    model.root = model.Entry.create(main.allocator, .dir, main.config.extended, path).dir().?;
-    model.root.entry.pack.blocks = stat.blocks;
-    model.root.entry.size = stat.size;
-    model.root.pack.dev = model.devices.getId(stat.dev);
+    const out = switch (state.out) {
+        .mem => |parent| sw: {
+            const p = parent orelse blk: {
+                model.root = model.Entry.create(main.allocator, .dir, main.config.extended, path).dir().?;
+                break :blk model.root;
+            };
+            state.status = .zeroing;
+            if (p.items > 10_000) main.handleEvent(false, true);
+            // Do the zeroStats() here, after the "root" entry has been
+            // stat'ed and opened, so that a fatal error on refresh won't
+            // zero-out the requested directory.
+            p.entry.zeroStats(p.parent);
+            state.status = .running;
+            p.entry.pack.blocks = stat.blocks;
+            p.entry.size = stat.size;
+            p.pack.dev = model.devices.getId(stat.dev);
+            break :sw .{ .mem = MemDir.init(p) };
+        },
+    };
 
     const d = main.allocator.create(Dir) catch unreachable;
     d.* = .{
         .name = main.allocator.dupe(u8, path) catch unreachable,
         .parent = null,
-        .out = .{ .mem = MemDir.init(model.root) },
+        .out = out,
     };
     return d;
 }
 
 
-pub fn draw() void {
+fn drawConsole() void {
+    const st = struct {
+        var ansi: ?bool = null;
+        var lines_written: usize = 0;
+    };
+    const stderr = std.io.getStdErr();
+    const ansi = st.ansi orelse blk: {
+        const t = stderr.supportsAnsiEscapeCodes();
+        st.ansi = t;
+        break :blk t;
+    };
+
+    var buf: [4096]u8 = undefined;
+    var strm = std.io.fixedBufferStream(buf[0..]);
+    var wr = strm.writer();
+    while (ansi and st.lines_written > 0) {
+        wr.writeAll("\x1b[1F\x1b[2K") catch {};
+        st.lines_written -= 1;
+    }
+
+    if (state.status == .running) {
+        var bytes: u64 = 0;
+        var files: u64 = 0;
+        for (state.threads) |*t| {
+            bytes +|= t.bytes_seen.load(.monotonic);
+            files += t.files_seen.load(.monotonic);
+        }
+        const r = ui.FmtSize.fmt(bytes);
+        wr.print("{} files / {s}{s}\n", .{files, r.num(), r.unit}) catch {};
+        st.lines_written += 1;
+
+        for (state.threads, 0..) |*t, i| {
+            const dir = blk: {
+                t.lock.lock();
+                defer t.lock.unlock();
+                break :blk if (t.current_dir) |d| d.path() else null;
+            };
+            wr.print("  #{}: {s}\n", .{i+1, ui.shorten(ui.toUtf8(dir orelse "(waiting)"), 73)}) catch {};
+            st.lines_written += 1;
+            if (dir) |p| main.allocator.free(p);
+        }
+    }
+
+    stderr.writeAll(strm.getWritten()) catch {};
+}
+
+
+fn drawProgress() void {
+    const st = struct { var animation_pos: usize = 0; };
+
     var bytes: u64 = 0;
     var files: u64 = 0;
     for (state.threads) |*t| {
         bytes +|= t.bytes_seen.load(.monotonic);
         files += t.files_seen.load(.monotonic);
     }
-    const r = ui.FmtSize.fmt(bytes);
-    std.debug.print("{} files / {s}{s}\n", .{files, r.num(), r.unit});
 
-    for (state.threads, 0..) |*t, i| {
+    ui.init();
+    const width = ui.cols -| 5;
+    const numthreads: u32 = @intCast(@min(state.threads.len, @max(1, ui.rows -| 10)));
+    const box = ui.Box.create(8 + numthreads, width, "Scanning...");
+    box.move(2, 2);
+    ui.addstr("Total items: ");
+    ui.addnum(.default, files);
+
+    if (width > 48) {
+        box.move(2, 30);
+        ui.addstr("size: ");
+        ui.addsize(.default, bytes);
+    }
+
+    for (0..numthreads) |i| {
+        box.move(3+@as(u32, @intCast(i)), 4);
         const dir = blk: {
+            const t = &state.threads[i];
             t.lock.lock();
             defer t.lock.unlock();
             break :blk if (t.current_dir) |d| d.path() else null;
         };
-        std.debug.print("  #{}: {s}\n", .{i, dir orelse "(waiting)"});
+        ui.addstr(ui.shorten(ui.toUtf8(dir orelse "(waiting)"), width -| 6));
         if (dir) |p| main.allocator.free(p);
     }
+
+    blk: {
+        state.last_error_lock.lock();
+        defer state.last_error_lock.unlock();
+        const err = state.last_error orelse break :blk;
+        box.move(4 + numthreads, 2);
+        ui.style(.bold);
+        ui.addstr("Warning: ");
+        ui.style(.default);
+        ui.addstr("error scanning ");
+        ui.addstr(ui.shorten(ui.toUtf8(err), width -| 28));
+        box.move(5 + numthreads, 3);
+        ui.addstr("some directory sizes may not be correct.");
+    }
+
+    if (state.need_confirm_quit) {
+        box.move(6 + numthreads, width -| 20);
+        ui.addstr("Press ");
+        ui.style(.key);
+        ui.addch('y');
+        ui.style(.default);
+        ui.addstr(" to confirm");
+    } else {
+        box.move(6 + numthreads, width -| 18);
+        ui.addstr("Press ");
+        ui.style(.key);
+        ui.addch('q');
+        ui.style(.default);
+        ui.addstr(" to abort");
+    }
+
+    if (main.config.update_delay < std.time.ns_per_s and width > 40) {
+        const txt = "Scanning...";
+        st.animation_pos += 1;
+        if (st.animation_pos >= txt.len*2) st.animation_pos = 0;
+        if (st.animation_pos < txt.len) {
+            box.move(6 + numthreads, 2);
+            for (txt[0..st.animation_pos + 1]) |t| ui.addch(t);
+        } else {
+            var i: u32 = txt.len-1;
+            while (i > st.animation_pos-txt.len) : (i -= 1) {
+                box.move(6 + numthreads, 2+i);
+                ui.addch(txt[i]);
+            }
+        }
+    }
 }
 
-pub fn keyInput(_: i32) void {
+
+fn drawError() void {
+    const width = ui.cols -| 5;
+    const box = ui.Box.create(6, width, "Scan error");
+
+    box.move(2, 2);
+    ui.addstr("Unable to open directory:");
+    box.move(3, 4);
+    ui.addstr(ui.shorten(ui.toUtf8(state.last_error.?), width -| 10));
+
+    box.move(4, width -| 27);
+    ui.addstr("Press any key to continue");
+}
+
+
+fn drawMessage(msg: []const u8) void {
+    const width = ui.cols -| 5;
+    const box = ui.Box.create(4, width, "Scan error");
+    box.move(2, 2);
+    ui.addstr(msg);
+}
+
+
+pub fn draw() void {
+    switch (main.config.scan_ui.?) {
+        .none => {},
+        .line => drawConsole(),
+        .full => switch (state.status) {
+            .done => {},
+            .err => drawError(),
+            .zeroing => {
+                const box = ui.Box.create(4, ui.cols -| 5, "Initializing");
+                box.move(2, 2);
+                ui.addstr("Clearing directory counts...");
+            },
+            .hlcnt => {
+                const box = ui.Box.create(4, ui.cols -| 5, "Finalizing");
+                box.move(2, 2);
+                ui.addstr("Counting hardlinks...");
+            },
+            .running => drawProgress(),
+        },
+    }
+}
+
+
+pub fn keyInput(ch: i32) void {
+    switch (state.status) {
+        .done => {},
+        .err => main.state = .browse,
+        .zeroing => {},
+        .hlcnt => {},
+        .running => {
+            switch (ch) {
+                'q' => {
+                    if (main.config.confirm_quit) state.need_confirm_quit = !state.need_confirm_quit
+                   else ui.quit();
+                },
+                'y', 'Y' => if (state.need_confirm_quit) ui.quit(),
+                else => state.need_confirm_quit = false,
+            }
+        },
+    }
 }