#!/usr/bin/env bash
# Step 1a Phase C Task 4 / spec v19 §11 + §12.3 boundary invariants.
#
# Verifies the following Jian crate boundary invariants from outside the
# Rust build system. Run from the repo root.
#
# (The former Invariant 1 — "the app crate must not depend directly on
#  any jian-* crate" — was dropped in Phase 1 Task 1.2 along with the
#  old placeholder crate. The Phase 7.3 reorg reintroduced a real
#  composition-root crate, `op-app`; reinstate an equivalent facade
#  check against it if/when op-app grows beyond a thin re-export.)
#
# Invariant 2 (§11.1, §12.3 — REVISED 2026-05-10): mobile targets
#   (`aarch64-linux-android`, `aarch64-apple-ios`) must NOT pull
#   `jian-host-desktop` (desktop GUI host glue — winit / glutin /
#   GLContextProvider impl that has no mobile equivalent). Per the
#   2026-05-10 user directive (jian will eventually need iOS and
#   Android), `jian-skia` is now ALLOWED on mobile targets — the
#   widget render stack (skia-safe + jian-skia + NativeBackend +
#   widget_host) compiles for iOS / Android cargo check, leaving
#   only the host-specific (Metal / Vulkan / event) integration to
#   Step 1f via the existing `EaglProvider` / `AndroidEglProvider`
#   plugin point.
#
# Invariant 3 (§11.1, §1.2): wasm32 builds of `op-host-web`
#   must NOT pull `jian-host-desktop` or `jian-skia` (skia-safe build.rs
#   fails on wasm32; Jian-core is wasm32-clean per P0.5 and is the only
#   Jian crate allowed in the bundle).
#
# Invariant 4 (§1.2): `op-host-web` must NOT depend on
#   `jian-host-desktop` at all — even as a non-default optional dep.
#
# Exit codes:
#   0  — all invariants pass.
#   1+ — one or more invariants fail; the failing crate names are
#         echoed before the script exits.
#
# Dependencies: `cargo`, `jq` (for cargo metadata JSON parsing).
set -euo pipefail

if ! command -v jq >/dev/null 2>&1; then
    echo "check-jian-boundaries.sh: \`jq\` is required but not installed." >&2
    echo "  apt: sudo apt-get install -y jq" >&2
    echo "  brew: brew install jq" >&2
    exit 2
fi

# ── Invariant 2: mobile targets don't pull jian-host-desktop. ─────────
# `cargo tree` honours `--target` cfg-gates so only the deps that
# actually compile under the mobile target are listed. `jian-skia` IS
# allowed on mobile (2026-05-10 user directive — widget render stack
# extends to iOS / Android); we still forbid `jian-host-desktop`
# because it pulls winit / glutin / desktop GLContextProvider impls
# that have no mobile equivalent.
for target in aarch64-linux-android aarch64-apple-ios; do
    tree_mobile="$(cargo tree -p op-host-native \
        --target "$target" \
        --prefix none \
        --edges normal,build 2>/dev/null || true)"
    forbidden_mobile="$(echo "$tree_mobile" \
        | grep -oE '\bjian-host-desktop\b' \
        | sort -u || true)"
    if [ -n "$forbidden_mobile" ]; then
        echo "INVARIANT 2 FAILED ($target): forbidden Jian crates in closure:" >&2
        echo "$forbidden_mobile" >&2
        exit 1
    fi
done

# ── Invariant 3: wasm32 has no jian-host-desktop / jian-skia. ──────────
# `jian-core` IS allowed (P0.5 wasm32-clean).
tree_wasm="$(cargo tree -p op-host-web \
    --target wasm32-unknown-unknown \
    --prefix none \
    --edges normal,build 2>/dev/null || true)"
forbidden_wasm="$(echo "$tree_wasm" \
    | grep -oE '\bjian-(host-desktop|skia)\b' \
    | sort -u || true)"
if [ -n "$forbidden_wasm" ]; then
    echo "INVARIANT 3 FAILED: wasm32 op-host-web pulls forbidden Jian crates:" >&2
    echo "$forbidden_wasm" >&2
    exit 1
fi

# ── Invariant 4: op-host-web has no jian-host-desktop dep. ───
# Distinct from invariant 3 (which checks the resolved closure on the
# wasm32 target): this checks the manifest itself across all targets.
# `cargo tree --all-targets` would include dev-deps; we explicitly
# filter `--edges normal,build` for the manifest-level invariant.
shell_web_deps="$(cargo tree -p op-host-web \
    --prefix none \
    --edges normal,build 2>/dev/null \
    | grep -E '\bjian-host-desktop\b' || true)"
if [ -n "$shell_web_deps" ]; then
    echo "INVARIANT 4 FAILED: op-host-web depends on jian-host-desktop:" >&2
    echo "$shell_web_deps" >&2
    exit 1
fi

echo "check-jian-boundaries.sh: all 3 Jian boundary invariants pass."