#!/usr/bin/env bash
# Builds "shannoncoat.app" — a menu bar app (no Dock icon, no window) with a
# custom icon (icon/AppIcon.icns — see icon/generate-icon.swift) for
# Finder/Spotlight. It stays running in the menu bar: click the status item
# to switch profiles, or open Manage Profiles… (Cmd+,) to add/remove one.
# Launch at Login is a toggle inside the app itself.
#
# Builds into ./.build (gitignored) rather than installing straight into an
# Applications dir — copy/drag the .app from there yourself. It's a fully
# native, self-contained bundle — no bundled script, so copying it anywhere
# after the build is safe.
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
SOURCES_DIR="$SCRIPT_DIR/Sources"

# Local, gitignored build configuration — currently just the code-signing
# identity, which otherwise has to be remembered and retyped on every
# build. See .env.example.
#
# Parsed rather than sourced, for two reasons: a stray command in the file
# shouldn't execute as a side effect of building, and this lets an existing
# environment variable win, so `SHANNONCOAT_SIGN_IDENTITY= ./build.sh`
# still forces a one-off ad-hoc build without editing the file.
ENV_FILE="$SCRIPT_DIR/.env"
if [[ -f "$ENV_FILE" ]]; then
  while IFS='=' read -r key value || [[ -n "$key" ]]; do
    key="${key#"${key%%[![:space:]]*}"}"   # strip leading whitespace
    key="${key#export }"
    [[ "$key" =~ ^[A-Za-z_][A-Za-z0-9_]*$ ]] || continue   # skips blanks and # comments
    value="${value%"${value##*[![:space:]]}"}"             # strip trailing whitespace
    value="${value%\"}"; value="${value#\"}"
    value="${value%\'}"; value="${value#\'}"
    [[ -n "${!key+set}" ]] && continue                     # already in the environment; leave it
    printf -v "$key" '%s' "$value"
    export "${key?}"
  done <"$ENV_FILE"
fi
VERSION_FILE="$SCRIPT_DIR/VERSION"
ICON_SRC="$SCRIPT_DIR/icon/AppIcon.icns"
OUT_DIR="${1:-$SCRIPT_DIR/.build}"
APP="$OUT_DIR/shannoncoat.app"

# Read from the repo's VERSION file so the .app and the script it bundles
# never report different numbers.
VERSION="$(cat "$VERSION_FILE" 2>/dev/null)"
[[ -n "$VERSION" ]] || { echo "error: couldn't read $VERSION_FILE" >&2; exit 1; }

mkdir -p "$OUT_DIR" "$APP/Contents/MacOS" "$APP/Contents/Resources"

[[ -f "$ICON_SRC" ]] || { echo "error: $ICON_SRC missing (see icon/generate-icon.swift)" >&2; exit 1; }
cp "$ICON_SRC" "$APP/Contents/Resources/AppIcon.icns"

cat >"$APP/Contents/Info.plist" <<PLIST
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>CFBundleName</key><string>shannoncoat</string>
  <key>CFBundleDisplayName</key><string>shannoncoat</string>
  <key>CFBundleIdentifier</key><string>com.local.shannoncoat</string>
  <key>CFBundleVersion</key><string>$VERSION</string>
  <key>CFBundleShortVersionString</key><string>$VERSION</string>
  <key>CFBundlePackageType</key><string>APPL</string>
  <key>CFBundleExecutable</key><string>launcher</string>
  <key>CFBundleIconFile</key><string>AppIcon</string>
  <key>LSUIElement</key><true/>
  <key>NSHighResolutionCapable</key><true/>
</dict>
</plist>
PLIST

command -v swiftc >/dev/null || { echo "error: swiftc not found (install Xcode Command Line Tools: xcode-select --install)" >&2; exit 1; }

# VERSION travels in Resources (not baked into the binary) so the About
# panel and the update checker read the same file this script stamped into
# Info.plist above.
cp "$VERSION_FILE" "$APP/Contents/Resources/VERSION"

# COMMIT is the short SHA the About tab appends to the version, so one dev
# build is distinguishable from another — left empty for a real release
# build, since the version number alone is unambiguous there. A release
# build is one of:
#   - SHANNONCOAT_RELEASE_BUILD set by release.yml, which already knows
#     for certain whether it's building a tag — trusted outright rather
#     than re-derived, since `git describe` needs full tag refs that a
#     CI runner's shallow checkout isn't guaranteed to have fetched.
#   - a local/manual build with HEAD sitting exactly on a tag (checked
#     via `git describe`, which is reliable here since a normal
#     non-shallow local clone has its full tag history).
GIT_SHA=""
if [[ -n "${SHANNONCOAT_RELEASE_BUILD:-}" ]]; then
  : # release build — leave GIT_SHA empty
elif git -C "$SCRIPT_DIR" rev-parse --git-dir >/dev/null 2>&1 \
    && ! git -C "$SCRIPT_DIR" describe --tags --exact-match >/dev/null 2>&1; then
  GIT_SHA="$(git -C "$SCRIPT_DIR" rev-parse --short HEAD 2>/dev/null || true)"
fi
printf '%s' "$GIT_SHA" >"$APP/Contents/Resources/COMMIT"

swiftc -O "$SOURCES_DIR"/*.swift -o "$APP/Contents/MacOS/launcher"

# Sign the bundle, not just the binary swiftc linker-signed for us — and
# with the bundle's real identifier rather than the "launcher" executable
# name codesign would otherwise infer.
#
# This matters well beyond tidiness, because the window tags need
# Accessibility. macOS ties that grant to a *properly signed* app's
# designated requirement, which survives a rebuild, but falls back to
# pinning an ad-hoc-signed app to its exact cdhash — and every build
# produces a new one. So with the ad-hoc default below, each build +
# reinstall silently invalidates the permission, while the app stays
# listed and stays ticked under Privacy & Security → Accessibility. It
# looks granted and isn't, and no amount of toggling that row fixes it:
# the stale entry has to be removed with "−" and the new build added back.
#
# To stop paying that tax on every build, make a self-signed code-signing
# certificate once (Keychain Access → Certificate Assistant → Create a
# Certificate…, type "Code Signing", self-signed) and point this at it:
#
#   SHANNONCOAT_SIGN_IDENTITY="My Local Signing Cert" ./build.sh
#
# then re-grant Accessibility one final time. The identity is stable from
# then on, so later builds keep the permission.
if [[ -n "${SHANNONCOAT_SIGN_IDENTITY:-}" ]]; then
  # An identity was asked for explicitly, so falling back to ad-hoc would
  # quietly reintroduce the very problem it was set to avoid — and a
  # release that ships ad-hoc revokes the Accessibility permission of
  # everyone who updates. Fail the build instead.
  codesign --force --sign "$SHANNONCOAT_SIGN_IDENTITY" \
    --identifier "com.local.shannoncoat" "$APP" \
    || { echo "error: signing with \"$SHANNONCOAT_SIGN_IDENTITY\" failed" >&2; exit 1; }
else
  codesign --force --sign - --identifier "com.local.shannoncoat" "$APP" >/dev/null 2>&1 \
    || echo "warning: codesign failed; Accessibility permission may not stick" >&2
fi

touch "$APP"
echo "Built: $APP"
echo "Copy it to /Applications (or ~/Applications) to install."