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

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
APP="$ROOT/dist/PromptGarage.app"
INSTALL_APP="/Applications/PromptGarage.app"
SOURCE_DB=""
INSTALL=false
LAUNCH=false
SOURCE_SNAPSHOT_BEFORE=""
SOURCE_SNAPSHOT_AFTER=""
INSTALL_STAGING_DIR=""
INSTALL_PREVIOUS_APP=""
INSTALL_REJECTED_APP=""
INSTALL_HAD_PREVIOUS=false
INSTALL_PREVIOUS_MOVED=false
INSTALL_NEW_IN_PLACE=false
INSTALL_TRANSACTION_ACTIVE=false
INSTALL_COMMITTED=false
CLEANUP_TRAP_ACTIVE=false

usage() {
    cat <<'EOF'
Usage: ./scripts/verify-mac.sh [options]

Options:
  --source-db PATH  Expose a real database read-only to integration tests via
                    PROMPTGARAGE_SOURCE_DB and prove its files are unchanged.
  --launch          Launch the verified dist/PromptGarage.app and prove that a
                    new PromptGarage process remains alive.
  --install         Replace /Applications/PromptGarage.app, then launch and
                    verify it. This is the only mode that writes to /Applications.
  -h, --help        Show this help.

Without --launch or --install, no app is opened. Without --install, nothing is
written to /Applications. This script never writes to --source-db.
EOF
}

fail() {
    printf 'verify-mac: %s\n' "$*" >&2
    exit 1
}

require_command() {
    command -v "$1" >/dev/null 2>&1 || fail "required command not found: $1"
}

while [[ $# -gt 0 ]]; do
    case "$1" in
        --source-db)
            [[ $# -ge 2 ]] || fail "--source-db requires a path"
            [[ -n "$2" ]] || fail "--source-db requires a non-empty path"
            SOURCE_DB="$2"
            shift 2
            ;;
        --launch)
            LAUNCH=true
            shift
            ;;
        --install)
            INSTALL=true
            LAUNCH=true
            shift
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            fail "unknown option: $1 (use --help)"
            ;;
    esac
done

assert_supported_host() {
    [[ "$(uname -s)" == "Darwin" ]] || fail "this verification must run on macOS"
    [[ "$(uname -m)" == "arm64" ]] || fail "an Apple Silicon (arm64) Mac is required"

    local macos_version macos_major xcode_version xcode_major swift_version
    macos_version="$(sw_vers -productVersion)"
    macos_major="${macos_version%%.*}"
    [[ "$macos_major" =~ ^[0-9]+$ ]] || fail "could not parse macOS version: $macos_version"
    (( macos_major >= 26 )) || fail "macOS 26 or newer is required; found $macos_version"

    xcode_version="$(xcodebuild -version | awk 'NR == 1 { print $2 }')"
    xcode_major="${xcode_version%%.*}"
    [[ "$xcode_major" =~ ^[0-9]+$ ]] || fail "could not parse Xcode version: $xcode_version"
    (( xcode_major >= 26 )) || fail "Xcode 26 or newer is required; found $xcode_version"

    swift_version="$(swift --version | sed -n '1s/.*Swift version \([0-9][0-9.]*\).*/\1/p')"
    [[ "$swift_version" == 6.2* ]] || fail "Swift 6.2 is required; found ${swift_version:-unknown}"
}

assert_exact_arm64() {
    local binary="$1"
    local architectures
    architectures="$(lipo -archs "$binary" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')"
    [[ "$architectures" == "arm64" ]] || fail "expected exactly arm64, found: ${architectures:-no architecture}"
}

snapshot_source_database() {
    local output="$1"
    local suffix candidate digest
    : > "$output"
    for suffix in "" "-wal" "-shm" "-journal"; do
        candidate="${SOURCE_DB}${suffix}"
        if [[ -e "$candidate" ]]; then
            if [[ ! -f "$candidate" ]]; then
                printf 'source database family contains a non-file: %s\n' "$candidate" >&2
                return 1
            fi
            digest="$(shasum -a 256 "$candidate" | awk '{ print $1 }')" || return 1
            printf 'present\t%s\t%s\n' "$suffix" "$digest" >> "$output"
        else
            printf 'absent\t%s\n' "$suffix" >> "$output"
        fi
    done
}

ensure_cleanup_trap() {
    if [[ "$CLEANUP_TRAP_ACTIVE" != true ]]; then
        trap cleanup_on_exit EXIT
        CLEANUP_TRAP_ACTIVE=true
    fi
}

rollback_install_transaction() {
    local rollback_ok=true

    [[ "$INSTALL_TRANSACTION_ACTIVE" == true ]] || return 0
    [[ "$INSTALL_COMMITTED" != true ]] || return 0

    if [[ "$INSTALL_NEW_IN_PLACE" == true ]]; then
        if [[ -e "$INSTALL_APP" || -L "$INSTALL_APP" ]]; then
            if mv "$INSTALL_APP" "$INSTALL_REJECTED_APP"; then
                INSTALL_NEW_IN_PLACE=false
            else
                printf 'verify-mac: automatic rollback could not move the replacement aside: %s\n' "$INSTALL_APP" >&2
                rollback_ok=false
            fi
        else
            printf 'verify-mac: automatic rollback could not find the installed replacement: %s\n' "$INSTALL_APP" >&2
            rollback_ok=false
        fi
    fi

    if [[ "$INSTALL_PREVIOUS_MOVED" == true ]]; then
        if [[ -e "$INSTALL_APP" || -L "$INSTALL_APP" ]]; then
            printf 'verify-mac: automatic rollback cannot restore over an occupied path: %s\n' "$INSTALL_APP" >&2
            rollback_ok=false
        elif mv "$INSTALL_PREVIOUS_APP" "$INSTALL_APP"; then
            INSTALL_PREVIOUS_MOVED=false
            printf 'verify-mac: previous app restored after verification failure\n' >&2
        else
            printf 'verify-mac: automatic rollback failed; previous app remains at: %s\n' "$INSTALL_PREVIOUS_APP" >&2
            rollback_ok=false
        fi
    elif [[ "$INSTALL_HAD_PREVIOUS" != true && ( -e "$INSTALL_REJECTED_APP" || -L "$INSTALL_REJECTED_APP" ) ]]; then
        printf 'verify-mac: replacement app removed after verification failure\n' >&2
    fi

    if [[ "$rollback_ok" == true ]]; then
        if [[ -n "$INSTALL_STAGING_DIR" ]] && ! rm -rf -- "$INSTALL_STAGING_DIR"; then
            printf 'verify-mac: rollback restored the install path, but could not clean transaction files: %s\n' "$INSTALL_STAGING_DIR" >&2
            return 1
        fi
        INSTALL_TRANSACTION_ACTIVE=false
        return 0
    fi
    printf 'verify-mac: install rollback incomplete; preserving transaction files at: %s\n' "$INSTALL_STAGING_DIR" >&2
    return 1
}

cleanup_on_exit() {
    local status=$?
    trap - EXIT
    if [[ -n "$SOURCE_SNAPSHOT_BEFORE" && -f "$SOURCE_SNAPSHOT_BEFORE" ]]; then
        if ! snapshot_source_database "$SOURCE_SNAPSHOT_AFTER"; then
            printf 'verify-mac: could not re-check source database after failure\n' >&2
            status=1
        elif ! cmp -s "$SOURCE_SNAPSHOT_BEFORE" "$SOURCE_SNAPSHOT_AFTER"; then
            printf 'verify-mac: SOURCE DATABASE CHANGED; refusing a successful result\n' >&2
            diff -u "$SOURCE_SNAPSHOT_BEFORE" "$SOURCE_SNAPSHOT_AFTER" >&2 || true
            status=1
        fi
    fi
    if (( status != 0 )); then
        rollback_install_transaction || status=1
    elif [[ "$INSTALL_TRANSACTION_ACTIVE" == true && "$INSTALL_COMMITTED" != true ]]; then
        printf 'verify-mac: install transaction reached EXIT before commit; rolling back\n' >&2
        rollback_install_transaction || status=1
        status=1
    fi
    [[ -z "$SOURCE_SNAPSHOT_BEFORE" ]] || rm -f "$SOURCE_SNAPSHOT_BEFORE"
    [[ -z "$SOURCE_SNAPSHOT_AFTER" ]] || rm -f "$SOURCE_SNAPSHOT_AFTER"
    exit "$status"
}

finish_source_guard() {
    [[ -n "$SOURCE_SNAPSHOT_BEFORE" ]] || return 0
    snapshot_source_database "$SOURCE_SNAPSHOT_AFTER" || fail "could not re-check source database"
    if ! cmp -s "$SOURCE_SNAPSHOT_BEFORE" "$SOURCE_SNAPSHOT_AFTER"; then
        diff -u "$SOURCE_SNAPSHOT_BEFORE" "$SOURCE_SNAPSHOT_AFTER" >&2 || true
        fail "source database or a SQLite sidecar changed during verification"
    fi
    rm -f "$SOURCE_SNAPSHOT_BEFORE" "$SOURCE_SNAPSHOT_AFTER"
    SOURCE_SNAPSHOT_BEFORE=""
    SOURCE_SNAPSHOT_AFTER=""
}

resolve_xcode_scheme() {
    local listing schemes candidate
    listing="$(xcodebuild -list 2>&1)" || fail "xcodebuild could not inspect this Swift package"
    schemes="$(printf '%s\n' "$listing" | awk '
        /^[[:space:]]*Schemes:[[:space:]]*$/ { inside = 1; next }
        inside && /^[[:space:]]+[^[:space:]]/ {
            line = $0
            sub(/^[[:space:]]+/, "", line)
            sub(/[[:space:]]+$/, "", line)
            print line
            next
        }
        inside && NF > 0 { exit }
    ')"

    if [[ -n "${PROMPTGARAGE_XCODE_SCHEME:-}" ]]; then
        if printf '%s\n' "$schemes" | grep -Fxq "$PROMPTGARAGE_XCODE_SCHEME"; then
            printf '%s\n' "$PROMPTGARAGE_XCODE_SCHEME"
            return 0
        fi
        fail "PROMPTGARAGE_XCODE_SCHEME is not available: $PROMPTGARAGE_XCODE_SCHEME"
    fi

    for candidate in PromptGarage-Package PromptGarage; do
        if printf '%s\n' "$schemes" | grep -Fxq "$candidate"; then
            printf '%s\n' "$candidate"
            return 0
        fi
    done

    printf 'Available Xcode schemes:\n%s\n' "${schemes:-<none>}" >&2
    fail "no PromptGarage package test scheme found; set PROMPTGARAGE_XCODE_SCHEME explicitly"
}

install_verified_app() {
    local install_parent staged_app

    [[ -d /Applications ]] || fail "/Applications does not exist"
    [[ -w /Applications ]] || fail "/Applications is not writable; install manually rather than rerunning with sudo"

    install_parent="$(dirname "$INSTALL_APP")"
    INSTALL_STAGING_DIR="$(mktemp -d "$install_parent/.PromptGarage.install.XXXXXX")" \
        || fail "could not create same-filesystem install staging directory"
    ensure_cleanup_trap
    INSTALL_TRANSACTION_ACTIVE=true
    staged_app="$INSTALL_STAGING_DIR/PromptGarage.app"
    INSTALL_PREVIOUS_APP="$INSTALL_STAGING_DIR/Previous-PromptGarage.app"
    INSTALL_REJECTED_APP="$INSTALL_STAGING_DIR/Rejected-PromptGarage.app"

    ditto "$APP" "$staged_app" || fail "could not stage the verified app"
    assert_exact_arm64 "$staged_app/Contents/MacOS/PromptGarage"
    codesign --verify --deep --strict --verbose=2 "$staged_app" \
        || fail "staged app failed code-signature verification; existing installation was not changed"

    if [[ -e "$INSTALL_APP" || -L "$INSTALL_APP" ]]; then
        mv "$INSTALL_APP" "$INSTALL_PREVIOUS_APP" \
            || fail "could not preserve the existing installation; it was not changed"
        INSTALL_HAD_PREVIOUS=true
        INSTALL_PREVIOUS_MOVED=true
    fi

    mv "$staged_app" "$INSTALL_APP" || fail "could not move the staged app into place"
    INSTALL_NEW_IN_PLACE=true

    assert_exact_arm64 "$INSTALL_APP/Contents/MacOS/PromptGarage"
    codesign --verify --deep --strict --verbose=2 "$INSTALL_APP" \
        || fail "installed app failed final code-signature verification"

    printf 'Installed app pending launch and source-family verification: %s\n' "$INSTALL_APP"
}

commit_install_transaction() {
    [[ "$INSTALL_TRANSACTION_ACTIVE" == true ]] || return 0
    if ! rm -rf -- "$INSTALL_STAGING_DIR"; then
        fail "installation passed, but transaction cleanup failed: $INSTALL_STAGING_DIR"
    fi
    INSTALL_COMMITTED=true
    INSTALL_TRANSACTION_ACTIVE=false
    INSTALL_PREVIOUS_MOVED=false
    INSTALL_NEW_IN_PLACE=false
    printf 'Installed verified app: %s\n' "$INSTALL_APP"
}

launch_and_verify_new_process() {
    local launch_app="$1"
    local expected_executable="$launch_app/Contents/MacOS/PromptGarage"
    local before_pids pid process_command launched_pid=""

    before_pids=" $(pgrep -x PromptGarage 2>/dev/null | tr '\n' ' ' || true) "
    open -n "$launch_app"

    for _ in 1 2 3 4 5 6 7 8 9 10; do
        for pid in $(pgrep -x PromptGarage 2>/dev/null || true); do
            case "$before_pids" in
                *" $pid "*) continue ;;
            esac
            process_command="$(ps -p "$pid" -o command= 2>/dev/null || true)"
            case "$process_command" in
                "$expected_executable"*) launched_pid="$pid" ;;
            esac
            [[ -z "$launched_pid" ]] || break
        done
        [[ -z "$launched_pid" ]] || break
        sleep 1
    done

    [[ -n "$launched_pid" ]] || fail "open returned, but no new process for $expected_executable stayed alive"
    sleep 2
    ps -p "$launched_pid" >/dev/null 2>&1 || fail "PromptGarage process $launched_pid exited during launch verification"
    printf 'Launch verified: PromptGarage PID %s\n' "$launched_pid"
}

for command_name in uname sw_vers xcodebuild swift python3 awk sed grep lipo codesign shasum cmp diff; do
    require_command "$command_name"
done
if [[ "$INSTALL" == true ]]; then
    for command_name in dirname ditto mktemp mv rm; do
        require_command "$command_name"
    done
fi
if [[ "$LAUNCH" == true ]]; then
    for command_name in open pgrep ps tr sleep; do
        require_command "$command_name"
    done
fi
if [[ -n "$SOURCE_DB" ]]; then
    for command_name in dirname basename mktemp rm; do
        require_command "$command_name"
    done
fi
assert_supported_host

if [[ -n "$SOURCE_DB" ]]; then
    [[ ! -L "$SOURCE_DB" ]] || fail "--source-db must not be a symlink; pass the real database path so SQLite sidecars are guarded"
    [[ -f "$SOURCE_DB" ]] || fail "source database not found: $SOURCE_DB"
    [[ -r "$SOURCE_DB" ]] || fail "source database is not readable: $SOURCE_DB"
    SOURCE_DB="$(cd "$(dirname "$SOURCE_DB")" && pwd -P)/$(basename "$SOURCE_DB")"
    [[ ! -L "$SOURCE_DB" ]] || fail "canonical --source-db resolved to a symlink; pass the real database path"
    SOURCE_SNAPSHOT_BEFORE="$(mktemp "${TMPDIR:-/tmp}/promptgarage-source-before.XXXXXX")" \
        || fail "could not create the source-before snapshot"
    ensure_cleanup_trap
    SOURCE_SNAPSHOT_AFTER="$(mktemp "${TMPDIR:-/tmp}/promptgarage-source-after.XXXXXX")" \
        || fail "could not create the source-after snapshot"
    snapshot_source_database "$SOURCE_SNAPSHOT_BEFORE" || fail "could not fingerprint source database"
    export PROMPTGARAGE_SOURCE_DB="$SOURCE_DB"
fi

cd "$ROOT"
if [[ -n "$SOURCE_DB" ]]; then
    python3 verification/verify_contract.py --source-db "$SOURCE_DB"
else
    python3 verification/verify_contract.py
fi

swift package resolve
swift test --arch arm64

XCODE_SCHEME="$(resolve_xcode_scheme)"
printf 'Running Xcode package tests with scheme: %s\n' "$XCODE_SCHEME"
xcodebuild \
    -scheme "$XCODE_SCHEME" \
    -destination 'platform=macOS,arch=arm64' \
    -configuration Debug \
    ARCHS=arm64 \
    ONLY_ACTIVE_ARCH=YES \
    test

"$ROOT/scripts/build-app.sh"
[[ -x "$APP/Contents/MacOS/PromptGarage" ]] || fail "packaged app executable missing"
assert_exact_arm64 "$APP/Contents/MacOS/PromptGarage"
codesign --verify --deep --strict --verbose=2 "$APP"

LAUNCH_APP="$APP"
if [[ "$INSTALL" == true ]]; then
    install_verified_app
    LAUNCH_APP="$INSTALL_APP"
fi
if [[ "$LAUNCH" == true ]]; then
    launch_and_verify_new_process "$LAUNCH_APP"
fi

finish_source_guard
if [[ "$INSTALL" == true ]]; then
    commit_install_transaction
fi
trap - EXIT

printf 'Mac automated verification passed.\n'
if [[ "$LAUNCH" == true ]]; then
    printf 'Complete verification/MAC_UI_SMOKE_CHECKLIST.md before calling the app done.\n'
else
    printf 'No app was launched. Use --launch or --install only when ready for the UI smoke test.\n'
fi