#!/usr/bin/env bash
# Source coverage for the CAD *widget* layer — the half
# tools/test-cad-coverage.sh cannot see.
#
# WHY THIS EXISTS
#
# The host-only harness measures the fourteen pure engine files by
# copying them into a crate with no Makepad in it. That is fast, needs no
# root, and is what the CI gate uses — but it is structurally blind to
# viewport*.rs, workspace*.rs, mod.rs, script_bindings.rs,
# cad_editor_sheet.rs and code_editor.rs, which are the files that handle
# every click, drag, keystroke and draw call in the editor.
#
# Those were called unmeasurable for a long time, including by the
# tooling's own documentation. They are not. They need the Makepad Linux
# packages — not a desktop, not a GPU, not a display server. With those
# installed, `cargo test -p nigig-build --lib` builds and runs, and it
# runs just as happily under -C instrument-coverage.
#
# The first run of this script reported 13.15% of lines over those ten
# files, with viewport_input.rs, viewport_render.rs, workspace_actions.rs,
# viewport_2d.rs, cad_editor_sheet.rs and code_editor.rs at exactly zero.
#
# COST
#
# ~6 minutes single-job from cold, most of it compiling the Makepad graph
# with instrumentation. Unlike the engine harness this needs apt packages
# and therefore root, which is why it is a separate script and not a flag
# on the other one.
#
# USAGE
#
#   bash tools/makepad-native-libs.sh --check     # what is missing
#   bash tools/makepad-native-libs.sh --install   # opt-in, apt-based
#   ./tools/test-cad-widget-coverage.sh
#
#   CAD_WIDGET_KEEP=1 ./tools/test-cad-widget-coverage.sh   # keep profraw
#                                                            + line report
#
# Deliberately NOT gated with floors yet. A floor at 13% reads as a
# blessing; the number is here to be driven up, and the first person to
# add a real input test should set one behind them.
set -Eeuo pipefail
IFS=$'\n\t'

ROOT="$(CDPATH= cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)"
CAD_REL="crates/apps/nigig-build/src/construction_frame/pages/workspace/cad"
TOOLCHAIN="$(sed -n 's/^channel = "\(.*\)"/\1/p' "$ROOT/rust-toolchain.toml")"
HOST_TRIPLE="${CAD_WIDGET_HOST:-x86_64-unknown-linux-gnu}"
WORK="$(mktemp -d "${TMPDIR:-/tmp}/cad-widget-coverage.XXXXXXXX")"
KEEP="${CAD_WIDGET_KEEP:-0}"

cleanup() {
  local status=$?
  if [[ "$KEEP" == "1" ]]; then
    echo "kept: $WORK" >&2
  else
    rm -rf "$WORK"
    echo "cleaned temporary coverage data" >&2
  fi
  exit "$status"
}
trap cleanup EXIT HUP INT TERM

# The build cache is reused by default: a cold instrumented build of the
# Makepad graph is minutes, and throwing it away every run would make
# this unusable in a loop. Point it somewhere else, or at $WORK, to get
# a hermetic run.
export CARGO_TARGET_DIR="${CAD_WIDGET_TARGET_DIR:-$WORK/target}"
export LLVM_PROFILE_FILE="$WORK/profiles/%p-%m.profraw"
export RUSTFLAGS="-C instrument-coverage"
export CARGO_NET_GIT_FETCH_WITH_CLI=true
export CARGO_BUILD_JOBS="${CAD_WIDGET_JOBS:-1}"
mkdir -p "$WORK/profiles"

if ! command -v cargo >/dev/null 2>&1; then
  echo "ERROR: cargo is not on PATH." >&2
  echo "  Unlike tools/test-cad-coverage.sh this script does not install a" >&2
  echo "  toolchain: it builds the real crate, so it uses yours." >&2
  exit 1
fi

if ! pkg-config --exists wayland-client x11 alsa 2>/dev/null; then
  echo "ERROR: the Makepad Linux packages are missing." >&2
  echo "  bash tools/makepad-native-libs.sh --check" >&2
  echo "  bash tools/makepad-native-libs.sh --install" >&2
  exit 1
fi

cd "$ROOT"
cargo test --locked -p nigig-build --lib

LLVM_BIN="$(rustc --print sysroot)/lib/rustlib/$HOST_TRIPLE/bin"
if [[ ! -x "$LLVM_BIN/llvm-profdata" ]]; then
  echo "ERROR: llvm-tools-preview is missing from the active toolchain." >&2
  echo "  rustup component add llvm-tools-preview --toolchain $TOOLCHAIN" >&2
  exit 1
fi

"$LLVM_BIN/llvm-profdata" merge -sparse "$WORK/profiles"/*.profraw \
  -o "$WORK/widget.profdata"

BIN="$(find "$CARGO_TARGET_DIR/debug/deps" -maxdepth 1 -type f -executable \
       -name 'nigig_build-*' ! -name '*.d' -printf '%T@ %p\n' \
     | sort -rn | head -1 | cut -d' ' -f2-)"
[[ -n "$BIN" ]] || { echo "no instrumented test binary found"; exit 1; }

# The widget files only. The engine files have their own report with
# floors; mixing them here would let a 97% engine hide a 0% input layer,
# which is exactly the arithmetic this script exists to prevent.
WIDGET_FILES=(
  mod.rs
  viewport.rs
  viewport_input.rs
  viewport_render.rs
  viewport_2d.rs
  workspace.rs
  workspace_actions.rs
  script_bindings.rs
  cad_editor_sheet.rs
  code_editor.rs
)
SOURCES=()
for f in "${WIDGET_FILES[@]}"; do
  SOURCES+=("$ROOT/$CAD_REL/$f")
done

echo
echo "=== CAD widget layer — the half the engine harness cannot see"
echo
"$LLVM_BIN/llvm-cov" report "$BIN" -instr-profile="$WORK/widget.profdata" \
  "${SOURCES[@]}" | sed "s|$ROOT/$CAD_REL/||"

if [[ "$KEEP" == "1" ]]; then
  "$LLVM_BIN/llvm-cov" show "$BIN" -instr-profile="$WORK/widget.profdata" \
    "${SOURCES[@]}" | grep -E '^ *[0-9]+\| *0\|' > "$WORK/uncovered-lines.txt" || true
  echo "uncovered line report: $WORK/uncovered-lines.txt" >&2
fi