#!/bin/sh
set -e

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
ROOT="$(dirname "$SCRIPT_DIR")"
SING_BOX="$ROOT/works/sing-box"
PATCH_DIR="$ROOT/works/patch"
OUTPUT="$ROOT/works/core"

if [ ! -d "$SING_BOX/.git" ]; then
    echo "Error: works/sing-box not found. Run update first." >&2
    exit 1
fi

echo "Initializing works/core/..."
rm -rf "$OUTPUT"
mkdir -p "$OUTPUT"
git init "$OUTPUT"

echo "Syncing sing-box files to works/core/..."
rsync -a --exclude='.git/' "$SING_BOX/" "$OUTPUT/"
VERSION="$(git -C "$SING_BOX" describe --tags --always 2>/dev/null || git -C "$SING_BOX" rev-parse --short HEAD)"
git -C "$OUTPUT" add -A
git -C "$OUTPUT" commit -m "upstream: $VERSION"

echo "Applying patches..."
applied=0
failed=0
failed_list=""

if [ -d "$PATCH_DIR" ]; then
    patch_list="$(mktemp)"
    trap 'rm -f "$patch_list"' EXIT
    find "$PATCH_DIR" -name "*.patch" | sort > "$patch_list"

    while IFS= read -r patch_file; do
        rel="${patch_file#$PATCH_DIR/}"
        rel="${rel%.patch}"
        dst="$OUTPUT/$rel"

        mkdir -p "$(dirname "$dst")"
        if patch --merge --no-backup-if-mismatch --force "$dst" < "$patch_file"; then
            applied=$((applied + 1))
        else
            echo "  FAILED:  $rel" >&2
            failed=$((failed + 1))
            failed_list="${failed_list}    ${rel}
"
        fi
    done < "$patch_list"
fi

git -C "$OUTPUT" add -A
git -C "$OUTPUT" commit -m "patches applied" --allow-empty

total=$((applied + failed))
echo ""
echo "Result: $applied/$total patches applied."
if [ "$failed" -gt 0 ]; then
    echo ""
    echo "Failed patches (merge conflicts written to files):"
    printf "%s" "$failed_list"
    echo ""
    echo "Resolve conflicts in works/core/, then run 'bin/generate' to update patches."
    exit 1
fi

echo "Done."