#!/usr/bin/env bash
set -euo pipefail

# ---------------------------------------------------------------------------
# rebuild-perspective.sh — rebuild the patched Perspective and re-vendor it
#
# pf_app runs a patched build of Perspective that exposes the column axis
# expand/collapse the engine already implements (split_by_depth, and
# expand_column/collapse_column). Upstream does not ship this yet, so the
# built packages are vendored into this directory as npm tarballs.
#
# Source of truth:  https://github.com/fleetside72/perspective
#                   branch column-axis-expand-collapse
#
# This script exists because vendored binaries are opaque: once the .tgz files
# are committed, nothing in the repo records how to regenerate them. Run this
# after changing the fork, then commit the resulting tarballs.
#
# Only needed on a machine that is changing the engine. Deploys just run
# `npm install`, which expands the committed tarballs - see ../README in this
# directory.
# ---------------------------------------------------------------------------

PSP="${PSP_DIR:-$HOME/perspective}"
BRANCH="${PSP_BRANCH:-column-axis-expand-collapse}"
VENDOR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# The four packages that must move together. Perspective's own docs are
# emphatic that loader, packages, data format and apache-arrow are one unit;
# vendoring a subset would reintroduce exactly the drift that causes trouble.
PACKAGES=(
    "rust/perspective-js"
    "rust/perspective-server"
    "rust/perspective-viewer"
    "packages/viewer-datagrid"
)

info() { echo -e "\033[0;34m==>\033[0m $*"; }
ok()   { echo -e "\033[0;32m  ✓\033[0m $*"; }
die()  { echo -e "\033[0;31m  ✗\033[0m $*" >&2; exit 1; }

# -- preflight --------------------------------------------------------------
[[ -d "$PSP" ]] || die "No Perspective checkout at $PSP.
    git clone https://github.com/fleetside72/perspective.git $PSP
    cd $PSP && git checkout $BRANCH
    Set PSP_DIR to use a different path."

command -v pnpm >/dev/null || die "pnpm not found. Perspective builds with pnpm, not npm."
command -v protoc >/dev/null || die "protoc not found.
    Its VERSION selects which protobuf source tree the build clones, and a
    version below 22 pulls a layout the build cannot consume. Needs >= 22
    (33.2 known good). Distro packages are usually far too old."

cmake_ver=$(cmake --version 2>/dev/null | head -1 | grep -oE '[0-9]+\.[0-9]+(\.[0-9]+)?') || die "cmake not found"
cmake_major=${cmake_ver%%.*}; cmake_minor=$(echo "$cmake_ver" | cut -d. -f2)
if (( cmake_major < 3 || (cmake_major == 3 && cmake_minor < 29) )); then
    die "cmake $cmake_ver is too old; Perspective needs >= 3.29.5.
    A user-level install works: pip3 install --user 'cmake>=3.29.5'"
fi

info "Perspective checkout: $PSP"
git -C "$PSP" rev-parse --abbrev-ref HEAD | grep -qx "$BRANCH" \
    || echo "  ! on branch $(git -C "$PSP" rev-parse --abbrev-ref HEAD), expected $BRANCH"
commit=$(git -C "$PSP" rev-parse --short HEAD)
dirty=$(git -C "$PSP" status --porcelain | wc -l)
echo "  commit $commit$([[ $dirty -gt 0 ]] && echo " (+$dirty uncommitted files)")"

# -- build ------------------------------------------------------------------
# `metadata` first: it generates docs/expression_gen.md, which perspective-client
# includes at compile time. Building a scope without it fails on the missing file.
info "Building (this takes ~40 minutes cold, a few minutes warm)…"
( cd "$PSP" && PSP_ONCE=1 PACKAGE="metadata,server,client,viewer,viewer-datagrid" pnpm run build )
ok "build complete"

# -- pack -------------------------------------------------------------------
info "Packing tarballs into $VENDOR"
rm -f "$VENDOR"/*.tgz
for p in "${PACKAGES[@]}"; do
    ( cd "$PSP/$p" && npm pack --pack-destination "$VENDOR" >/dev/null )
    ok "$(basename "$p")"
done

# -- record provenance ------------------------------------------------------
# A committed .tgz is an opaque binary; without this the tie back to source is
# only in someone's memory.
cat > "$VENDOR/PROVENANCE.txt" <<EOF
Built from https://github.com/fleetside72/perspective
  branch  $BRANCH
  commit  $(git -C "$PSP" rev-parse HEAD)
  based on $(git -C "$PSP" describe --tags --abbrev=0 2>/dev/null || echo 'unknown')
  built   $(date -u +%Y-%m-%dT%H:%M:%SZ) on $(hostname)
  dirty   $dirty uncommitted file(s) in the source tree at build time

Regenerate with ui/vendor/rebuild-perspective.sh
EOF

echo
ls -la "$VENDOR"/*.tgz | awk '{printf "  %-52s %5.1f MB\n", $NF, $5/1048576}'
echo
ok "Done. Now: cd ui && npm install && git add vendor && git commit"
[[ $dirty -gt 0 ]] && echo -e "\033[1;33m  !\033[0m source tree had uncommitted changes — push them to the fork first"
exit 0