#!/bin/bash
# ============================================================================
# Diet Guard installer: log-to-unlock gate with a freely-editable budget.
#
# Usage: bash install.sh
#
# What it does:
#   1. Ensures system deps (setxkbmap for VT-disable, requests for OFF lookups)
#   2. pip-installs this package + gatelock into system Python's user
#      site-packages (the systemd service runs /usr/bin/python directly, not
#      a venv, so the package must live where that interpreter can find it —
#      see CLAUDE.md's "Production dependency installation" section)
#   3. Installs + enables the systemd user timer that fires the gate every ~15m
#   4. Installs + enables the systemd user timer that syncs the log every ~15m
#      (the sync itself stays unconfigured -- and a no-op -- until you create
#      a sync token; see the reminder this step prints)
#   5. Sets your initial daily budget from biometrics (only if not already set;
#      it stays freely editable afterward from the gate or the phone app)
# ============================================================================

set -euo pipefail

# Split declare/assign so the command-substitution exit code is not masked (SC2155).
SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
readonly SCRIPT_DIR
readonly REPO_DIR="$SCRIPT_DIR"
readonly SERVICE_SRC="$SCRIPT_DIR/diet-guard-gate.service"
readonly TIMER_SRC="$SCRIPT_DIR/diet-guard-gate.timer"
readonly SYNC_SERVICE_SRC="$SCRIPT_DIR/diet-guard-sync.service"
readonly SYSTEMD_USER_DIR="$HOME/.config/systemd/user"
readonly DATA_DIR="$HOME/.local/share/diet_guard"
readonly BUDGET_FILE="$DATA_DIR/.budget"
readonly SYNC_TOKEN_FILE="$HOME/.config/diet_guard/sync_token"

echo "=== Diet Guard Installer ==="

# 1. System dependencies ------------------------------------------------------
echo "[1/5] Checking system dependencies..."
if ! command -v setxkbmap &>/dev/null; then
    echo "  Installing xorg-setxkbmap (gate disables VT switching while locked)..."
    sudo pacman -S --noconfirm xorg-setxkbmap
else
    echo "  setxkbmap present"
fi

# 2. Install this package + its dependencies into system Python -------------
echo "[2/5] Installing diet_guard + dependencies for /usr/bin/python..."
/usr/bin/python3 -m pip install --user --break-system-packages -e "$REPO_DIR"
echo "  Installed. Verifying import..."
/usr/bin/python3 -c "import diet_guard; import gatelock" \
    && echo "  diet_guard and gatelock import cleanly from the system interpreter."

# 3. systemd user timer + service (gate) -------------------------------------
echo "[3/5] Installing the gate's systemd user timer + service..."
mkdir -p "$SYSTEMD_USER_DIR"
cp "$SERVICE_SRC" "$SYSTEMD_USER_DIR/diet-guard-gate.service"
cp "$TIMER_SRC" "$SYSTEMD_USER_DIR/diet-guard-gate.timer"
systemctl --user daemon-reload
systemctl --user enable --now diet-guard-gate.timer
echo "  Timer enabled and started (fires the gate every ~15 min)."

# 4. Retire the old periodic sync timer ---------------------------------------
# Sync is event-driven now (before a lock, after a meal is logged -- see
# diet_guard/_sync_events.py), so the ~15 min timer is gone. Removing the unit
# from the repo does NOT stop an already-installed copy: without this block it
# would keep firing forever from $SYSTEMD_USER_DIR with no unit file in git to
# explain it. `|| true` because a fresh machine has no such unit and `disable`
# exits non-zero there, which would abort the install under `set -euo pipefail`.
echo "[4/5] Removing the retired periodic sync timer (sync is event-driven)..."
systemctl --user disable --now diet-guard-sync.timer 2>/dev/null || true
rm -f "$SYSTEMD_USER_DIR/diet-guard-sync.timer"
# The *service* stays: it is how a manual one-off tick is run
# (`systemctl --user start diet-guard-sync`). Only the timer is retired.
cp "$SYNC_SERVICE_SRC" "$SYSTEMD_USER_DIR/diet-guard-sync.service"
systemctl --user daemon-reload
echo "  Periodic sync timer removed; 'python -m diet_guard sync' still works."
if [[ -e "$SYNC_TOKEN_FILE" ]]; then
    echo "  Sync token already present at $SYNC_TOKEN_FILE."
else
    echo "  No sync token yet at $SYNC_TOKEN_FILE -- sync will no-op (and log a"
    echo "  failure) after every meal you log, until you create a GitHub PAT"
    echo "  scoped to the diet-guard-sync repo's contents and save it there,"
    echo "  mode 600: chmod 600 \"$SYNC_TOKEN_FILE\""
fi

# 5. Set the initial daily budget ---------------------------------------------
echo "[5/5] Setting your initial daily budget..."
if [[ -e "$BUDGET_FILE" ]]; then
    echo "  Budget already set at $BUDGET_FILE - skipping init."
    echo "  Edit it any time from the gate's calendar tab or the phone app."
else
    echo "  Enter your biometrics (used once then discarded to compute a"
    echo "  starting value; you can change the number itself any time from"
    echo "  the gate's calendar tab or the phone app):"
    python -m diet_guard init
fi

echo "=== Installation complete ==="
echo "The gate checks every ~15 min and locks until you log a meal once a meal"
echo "slot passes unlogged (08:00/12:00/16:00/20:00 by default; editable)."
echo "Test the lock now (safe, closeable): python -m diet_guard gate --demo"