#!/usr/bin/env bash
# LLVM source-coverage for the p2p-intel engine crates, with an enforced floor.
#
# Same design as tools/test-pdf-coverage.sh: coverage that is only ever
# *printed* drifts down, so this fails the build rather than reporting.
#
# What is measured: the five pure-Rust crates plus the Makepad view model.
# What is not: `p2p-makepad/src/dashboard.rs` and the app binary, which need
# a GPU and a windowing backend. That exclusion is the reason the view model
# is a separate file — see the module docs there. Excluding a file you have
# not first emptied of logic is how `spreadsheet-ui/grid.rs` hid 36 pure
# functions behind a file-level skip.
#
# Usage:
#   ./tools/test-p2p-coverage.sh              # enforce the floor
#   P2P_COVERAGE_REPORT_ONLY=1 ./tools/test-p2p-coverage.sh
#
# Runs entirely inside one temporary directory: its own rustup, cargo home
# and target dir, all removed on exit.

set -Eeuo pipefail
IFS=$'\n\t'

ROOT="$(CDPATH= cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)"
TOOLCHAIN="${RUST_TOOLCHAIN:-1.97.1}"
SRC="$ROOT/crates/apps/p2p-intel"

# Measured at 93.9% of lines (excluding the CLI shell) when written.
TOTAL_FLOOR="${P2P_COVERAGE_TOTAL_FLOOR:-90}"

# Per-file floors for the files that carry a decision. A single whole-stack
# number hides the failure this exists to catch: spread.rs could fall to 5%
# while the total moves a point, because the total is dominated by types.rs.
PER_FILE_FLOORS="${P2P_COVERAGE_PER_FILE_FLOORS:-\
p2p-core/src/types.rs:90
p2p-core/src/config.rs:95
p2p-analyzer/src/spread.rs:96
p2p-tracker/src/inventory.rs:94
p2p-tracker/src/trade.rs:94
p2p-scanner/src/parser.rs:91
p2p-alerter/src/lib.rs:95
p2p-makepad/src/view_model.rs:93
p2p-makepad/src/chime.rs:95
p2p-scanner/src/client.rs:90
p2p-core/src/drift.rs:95
p2p-alerter/src/notify.rs:95
p2p-analyzer/src/rail.rs:88
p2p-analyzer/src/panel.rs:95
p2p-analyzer/src/deal_bridge.rs:95}"

WORK="$(mktemp -d "${TMPDIR:-/tmp}/p2p-coverage.XXXXXXXX")"
cleanup() {
  local status=$?
  if [ "${KEEP_TEST_ENV:-0}" = "1" ]; then
    printf 'kept coverage environment at %s\n' "$WORK" >&2
  else
    chmod -R u+w "$WORK" 2>/dev/null || true
    rm -rf "$WORK"
  fi
  exit "$status"
}
trap cleanup EXIT HUP INT TERM

export RUSTUP_HOME="$WORK/rustup"
export CARGO_HOME="$WORK/cargo"
export CARGO_TARGET_DIR="$WORK/target"
export PATH="$CARGO_HOME/bin:$PATH"
export LLVM_PROFILE_FILE="$WORK/profiles/%p-%m.profraw"
export RUSTFLAGS="-C instrument-coverage -C codegen-units=1 -C opt-level=0"
mkdir -p "$WORK/profiles"

printf 'installing Rust %s with llvm-tools\n' "$TOOLCHAIN"
curl --fail --silent --show-error --location https://sh.rustup.rs -o "$WORK/rustup-init"
chmod 700 "$WORK/rustup-init"
"$WORK/rustup-init" -y --profile minimal --default-toolchain "$TOOLCHAIN" \
  --component llvm-tools-preview --no-modify-path >/dev/null

printf 'running the p2p-intel suites under instrumentation\n'
# --workspace without --features ui: the dashboard widget and the app binary
# need a GPU. Everything with a decision in it is in the default feature set.
cargo test --manifest-path "$SRC/Cargo.toml" --workspace \
  >"$WORK/test.log" 2>&1 || { cat "$WORK/test.log"; exit 1; }
grep -E 'test result' "$WORK/test.log" | tail -20

HOST="$(rustc -vV | sed -n 's/^host: //p')"
LLVM_BIN="$RUSTUP_HOME/toolchains/$TOOLCHAIN-$HOST/lib/rustlib/$HOST/bin"

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

mapfile -t BINARIES < <(
  find "$CARGO_TARGET_DIR/debug/deps" -maxdepth 1 -type f -executable \
    ! -name '*.d' ! -name '*.so' | sort
)
OBJECTS=()
for bin in "${BINARIES[@]}"; do
  OBJECTS+=(-object "$bin")
done
if [ "${#OBJECTS[@]}" -eq 0 ]; then
  echo 'no instrumented binaries were produced' >&2
  exit 1
fi

# Only the crates' own `src/` trees count. `dashboard.rs` is excluded here
# because it cannot be reached without a windowing backend.
# `p2p-cli/src/main.rs` is excluded and measures 0%: it is argument
# parsing and println, and every decision it makes is delegated to a
# library crate that is measured. This exclusion is only defensible
# because the file was kept empty of logic — the moment a rule moves
# into it, it must come out of this list.
IGNORE='(/cargo/registry|/cargo/git|/rustc/|/tests/|/src/bin/|dashboard\.rs|p2p-cli/src/main\.rs)'

printf '\n=== per-file coverage ===\n'
"$LLVM_BIN/llvm-cov" report "${OBJECTS[@]}" \
  -instr-profile="$WORK/coverage.profdata" \
  -ignore-filename-regex="$IGNORE" \
  | tee "$WORK/report.txt"

TOTAL_LINE="$(grep -E '^TOTAL' "$WORK/report.txt" | tail -1)"
TOTAL_COVER="$(echo "$TOTAL_LINE" | awk '{print $(NF-3)}' | tr -d '%')"

printf '\ntotal line coverage: %s%% (floor %s%%)\n' "$TOTAL_COVER" "$TOTAL_FLOOR"

if [ "${P2P_COVERAGE_REPORT_ONLY:-0}" = "1" ]; then
  echo 'report-only mode: the floor was not enforced'
  exit 0
fi

FAILED=0
awk -v floor="$TOTAL_FLOOR" -v got="$TOTAL_COVER" 'BEGIN { exit !(got+0 < floor+0) }' \
  && { printf 'FAIL: total %s%% is below the %s%% floor\n' "$TOTAL_COVER" "$TOTAL_FLOOR" >&2; FAILED=1; }

while IFS= read -r entry; do
  [ -z "$entry" ] && continue
  file="${entry%:*}"
  floor="${entry##*:}"
  line="$(grep -F "$file" "$WORK/report.txt" | tail -1 || true)"
  if [ -z "$line" ]; then
    printf 'FAIL: %s has a floor but was not measured\n' "$file" >&2
    FAILED=1
    continue
  fi
  cover="$(echo "$line" | awk '{print $(NF-3)}' | tr -d '%')"
  if awk -v f="$floor" -v g="$cover" 'BEGIN { exit !(g+0 < f+0) }'; then
    printf 'FAIL: %s at %s%% is below its %s%% floor\n' "$file" "$cover" "$floor" >&2
    FAILED=1
  else
    printf 'ok:   %s at %s%% (floor %s%%)\n' "$file" "$cover" "$floor"
  fi
done <<< "$PER_FILE_FLOORS"

exit "$FAILED"