#!/usr/bin/env sh
# One-time installer: builds the binary and ensures it's on your PATH via ~/.local/bin.
set -euo pipefail

ROOT="$(cd -- "$(dirname "$0")/.." && pwd)"
BIN_DIR="$ROOT/bin"
BIN="$BIN_DIR/img2pdf"
GOFLAGS_DEFAULT="-tags=wayland"
CGO_CFLAGS_DEFAULT="-D_GNU_SOURCE"

# Simple spinner for long-running steps (cycles 10 dots inline).
run_with_spinner() {
  label="$1"; shift
  printf "%s" "$label"
  (
    count=0
    while :; do
      printf "."
      count=$(( (count + 1) % 10 ))
      if [ "$count" -eq 0 ]; then
        printf "\r%s" "$label"
      fi
      sleep 0.35
    done
  ) &
  spid=$!
  "$@"; status=$?
  kill "$spid" 2>/dev/null
  printf "\n"
  return $status
}

export GOCACHE="${GOCACHE:-$ROOT/.cache/go-build}"
export GOMODCACHE="${GOMODCACHE:-$ROOT/.cache/go-mod}"
export GOFLAGS="${GOFLAGS:-$GOFLAGS_DEFAULT}"
export CGO_CFLAGS="${CGO_CFLAGS:-$CGO_CFLAGS_DEFAULT}"
export CGO_CXXFLAGS="${CGO_CXXFLAGS:-$CGO_CFLAGS}"
mkdir -p "$GOCACHE" "$GOMODCACHE" "$BIN_DIR"

patch_glfw_wayland() {
  # Drop the redundant _GNU_SOURCE define in GLFW's Wayland file to avoid macro redefinition warnings.
  local wl_file="$GOMODCACHE/github.com/go-gl/glfw/v3.3/glfw@v0.0.0-20221017161538-93cebf72946b/glfw/src/wl_window.c"
  if [ -f "$wl_file" ] && grep -q '^#define _GNU_SOURCE$' "$wl_file"; then
    chmod u+w "$wl_file"
    tmp="$(mktemp)"
    sed '/^#define _GNU_SOURCE$/d' "$wl_file" >"$tmp" && mv "$tmp" "$wl_file"
  fi
}

# Ensure dependencies are present (generates go.sum). If this fails, likely due to blocked network.
ensure_deps() {
  if [ ! -f "$ROOT/go.sum" ]; then
    run_with_spinner "Resolving dependencies" env GOCACHE="$GOCACHE" GOMODCACHE="$GOMODCACHE" go mod tidy || {
      echo "Failed to resolve dependencies (network or permissions issue). Please run:"
      echo "  GOMODCACHE=\"$GOMODCACHE\" GOCACHE=\"$GOCACHE\" go mod tidy"
      exit 1
    }
  fi
  # Prefetch modules; if it fails (offline), warn but continue to build from cache.
  if ! run_with_spinner "Downloading modules" env GOCACHE="$GOCACHE" GOMODCACHE="$GOMODCACHE" go mod download 2>/dev/null; then
    echo "Warning: could not download modules (maybe offline). Continuing with existing cache."
  fi
}

cd "$ROOT"
ensure_deps
patch_glfw_wayland
if ! run_with_spinner "Building img2pdf" env GOCACHE="$GOCACHE" GOMODCACHE="$GOMODCACHE" GOFLAGS="$GOFLAGS" go build -o "$BIN" ./cmd/img2pdf; then
  echo "Build failed. See errors above."
  exit 1
fi
echo "Built: $BIN"
echo "Use: ./img2pdf (from repo root)"