#!/bin/bash
# Birthday & Gift Tracker
# Tracks family birthdays, sends reminders, suggests gifts
# Checks daily at 9:00 AM

set -e

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
DATA_FILE="$SCRIPT_DIR/birthdays.json"
LOG_FILE="$SCRIPT_DIR/reminder-log.json"
source "$SCRIPT_DIR/../../.env" 2>/dev/null || true

TELEGRAM_CHAT="${TELEGRAM_CHAT:-1793951355}"

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1"
}

# Initialize data file if not exists
init_data() {
    if [[ ! -f "$DATA_FILE" ]]; then
        log "Creating birthday database..."
        cat > "$DATA_FILE" << 'EOF'
{
  "people": [
    {
      "name": "Grace Martin",
      "relationship": "Mum",
      "birthday": "06-02",
      "birth_year": 1951,
      "notes": "Cancer treatment ongoing - be extra thoughtful. Loves gardening, cooking, family time.",
      "gift_ideas": ["Flowers", "Gardening supplies", "Photo album", "Day spa voucher", "Home-cooked meal"],
      "past_gifts": []
    },
    {
      "name": "Harvey Martin", 
      "relationship": "Dad",
      "birthday": "12-08",
      "birth_year": 1949,
      "notes": "Full-time carer for Grace. Needs respite/support. Loves tech gadgets, wine, coffee.",
      "gift_ideas": ["Ember mug", "Wine subscription", "Coffee beans", "Tech gadget", "Day out voucher"],
      "past_gifts": []
    },
    {
      "name": "Elizabeth Martin",
      "relationship": "Sister", 
      "birthday": "09-11",
      "birth_year": 1990,
      "notes": "Vegan - avoid food gifts unless specifically vegan. Creative, environmentally conscious.",
      "gift_ideas": ["Vegan cookbook", "Eco-friendly products", "Plants", "Art supplies", "Experience gift"],
      "past_gifts": []
    },
    {
      "name": "Alexander",
      "relationship": "Godson/Cousin",
      "birthday": "07-XX",
      "birth_year": 2016,
      "notes": "8 years old (born July 2016). Loves games, books, LEGO, sports.",
      "gift_ideas": ["LEGO set", "Books", "Board games", "Sports equipment", "Science kit"],
      "past_gifts": []
    },
    {
      "name": "Mia Martin",
      "relationship": "Doggo 🐕",
      "birthday": "XX-XX",
      "notes": "14 years old, beloved geriatric girl. Treats, toys, comfy beds.",
      "gift_ideas": ["Premium dog treats", "Comfy bed", "New toy", "Grooming session"],
      "past_gifts": []
    }
  ],
  "settings": {
    "reminder_weeks_before": 2,
    "reminder_days_before": 7,
    "reminder_day_of": true
  }
}
EOF
    fi
    
    if [[ ! -f "$LOG_FILE" ]]; then
        echo '{"sent_reminders": []}' > "$LOG_FILE"
    fi
}

# Get today's date in MM-DD format
today_mmdd() {
    date +%m-%d
}

# Get today's date in YYYY-MM-DD format
today_yyyymmdd() {
    date +%Y-%m-%d
}

# Calculate days until birthday
days_until_birthday() {
    local bday_mmdd="$1"
    local today=$(today_yyyymmdd)
    local current_year=$(date +%Y)
    
    # Handle missing day (XX)
    if [[ "$bday_mmdd" == *"XX"* ]]; then
        echo "unknown"
        return
    fi
    
    local bday_this_year="$current_year-$bday_mmdd"
    local bday_ts=$(date -d "$bday_this_year" +%s 2>/dev/null || echo "0")
    local today_ts=$(date -d "$today" +%s)
    
    # If birthday passed this year, calculate for next year
    if ((bday_ts < today_ts)); then
        ((current_year++))
        bday_this_year="$current_year-$bday_mmdd"
        bday_ts=$(date -d "$bday_this_year" +%s)
    fi
    
    local diff=$(( (bday_ts - today_ts) / 86400 ))
    echo "$diff"
}

# Check if reminder already sent today
reminder_sent() {
    local person="$1"
    local type="$2"
    local today=$(today_yyyymmdd)
    
    grep -q "\"$today-$person-$type\"" "$LOG_FILE" 2>/dev/null
}

# Log that reminder was sent
log_reminder() {
    local person="$1"
    local type="$2"
    local today=$(today_yyyymmdd)
    
    # Add to log
    local temp_file=$(mktemp)
    jq --arg key "$today-$person-$type" '.sent_reminders += [$key]' "$LOG_FILE" > "$temp_file"
    mv "$temp_file" "$LOG_FILE"
}

# Clean old reminders from log (keep last 90 days)
cleanup_log() {
    local cutoff=$(date -d "90 days ago" +%Y-%m-%d)
    local temp_file=$(mktemp)
    
    jq --arg cutoff "$cutoff" '.sent_reminders |= map(select(. > $cutoff or length < 10))' "$LOG_FILE" > "$temp_file" 2>/dev/null || true
    mv "$temp_file" "$LOG_FILE" 2>/dev/null || true
}

# Send Telegram message
send_telegram() {
    local message="$1"
    
    curl -s -X POST "https://api.telegram.org/bot${TELEGRAM_BOT_TOKEN}/sendMessage" \
        -H "Content-Type: application/json" \
        -d "{
            \"chat_id\": \"$TELEGRAM_CHAT\",
            \"text\": \"$message\",
            \"parse_mode\": \"Markdown\"
        }" > /dev/null || {
        log "ERROR: Failed to send Telegram message"
        return 1
    }
}

# Generate gift suggestions text
gift_suggestions() {
    local ideas=$(echo "$1" | jq -r '.gift_ideas | join(", ")')
    local notes=$(echo "$1" | jq -r '.notes')
    local past=$(echo "$1" | jq -r '.past_gifts | if length > 0 then "Past gifts: " + join(", ") else "" end')
    
    local text="💡 *Gift Ideas:* $ideas"
    if [[ -n "$past" && "$past" != "Past gifts: " ]]; then
        text+="\n🎁 $past"
    fi
    text+="\n📝 *Notes:* $notes"
    
    echo "$text"
}

# Check birthdays and send reminders
check_birthdays() {
    log "Checking birthdays..."
    
    local people=$(jq -c '.people[]' "$DATA_FILE")
    local settings=$(jq '.settings' "$DATA_FILE")
    local weeks_before=$(echo "$settings" | jq -r '.reminder_weeks_before')
    local days_before=$(echo "$settings" | jq -r '.reminder_days_before')
    
    local reminders_sent=0
    
    while IFS= read -r person; do
        local name=$(echo "$person" | jq -r '.name')
        local relationship=$(echo "$person" | jq -r '.relationship')
        local birthday=$(echo "$person" | jq -r '.birthday')
        local birth_year=$(echo "$person" | jq -r '.birth_year // empty')
        
        # Skip if no specific date
        if [[ "$birthday" == *"XX"* ]]; then
            continue
        fi
        
        local days_until=$(days_until_birthday "$birthday")
        
        # Calculate age if birth year known
        local age_text=""
        if [[ -n "$birth_year" && "$birth_year" != "null" ]]; then
            local current_year=$(date +%Y)
            local age=$((current_year - birth_year))
            if ((days_until < 365)); then
                age_text=" (turning $age)"
            fi
        fi
        
        # Check reminders
        local should_remind=false
        local reminder_type=""
        local message=""
        
        if ((days_until == 0)); then
            reminder_type="today"
            if ! reminder_sent "$name" "$reminder_type"; then
                message="🎂 *Birthday Today!*\n\n*$name* — your $relationship$age_text\n\nDon't forget to call/message them! 💝"
                local gifts=$(gift_suggestions "$person")
                message+="\n\n$gifts"
                should_remind=true
            fi
        elif ((days_until == days_before)); then
            reminder_type="week"
            if ! reminder_sent "$name" "$reminder_type"; then
                message="📅 *Birthday Reminder*\n\n*$name* — your $relationship$age_text\nBirthday in *$days_until days* ($birthday)\n\nTime to plan something! 🎁"
                local gifts=$(gift_suggestions "$person")
                message+="\n\n$gifts"
                should_remind=true
            fi
        elif ((days_until == weeks_before * 7)); then
            reminder_type="twoweeks"
            if ! reminder_sent "$name" "$reminder_type"; then
                message="📅 *Upcoming Birthday*\n\n*$name* — your $relationship$age_text\nBirthday in *$days_until days* ($birthday)\n\nStart thinking about gifts! 🎁"
                local gifts=$(gift_suggestions "$person")
                message+="\n\n$gifts"
                should_remind=true
            fi
        fi
        
        if [[ "$should_remind" == true ]]; then
            log "Sending $reminder_type reminder for $name"
            send_telegram "$message"
            log_reminder "$name" "$reminder_type"
            ((reminders_sent++))
        fi
        
    done <<< "$people"
    
    log "Sent $reminders_sent reminders"
}

# Add/update a person (can be called manually)
add_person() {
    local name="$1"
    local relationship="$2"
    local birthday="$3"  # MM-DD format
    local notes="$4"
    
    local temp_file=$(mktemp)
    jq --arg name "$name" \
       --arg rel "$relationship" \
       --arg bday "$birthday" \
       --arg notes "$notes" \
       '.people += [{"name": $name, "relationship": $rel, "birthday": $bday, "notes": $notes, "gift_ideas": [], "past_gifts": []}]' \
       "$DATA_FILE" > "$temp_file"
    mv "$temp_file" "$DATA_FILE"
    
    log "Added $name to birthday tracker"
}

# Log a past gift
log_gift() {
    local name="$1"
    local gift="$2"
    local year="${3:-$(date +%Y)}"
    
    local temp_file=$(mktemp)
    jq --arg name "$name" \
       --arg gift "$gift ($year)" \
       '(.people[] | select(.name == $name)).past_gifts += [$gift]' \
       "$DATA_FILE" > "$temp_file"
    mv "$temp_file" "$DATA_FILE"
    
    log "Logged gift for $name: $gift"
}

# Main
main() {
    case "${1:-check}" in
        check)
            init_data
            check_birthdays
            cleanup_log
            ;;
        add)
            add_person "$2" "$3" "$4" "$5"
            ;;
        gift)
            log_gift "$2" "$3" "$4"
            ;;
        list)
            jq '.people[] | {name, relationship, birthday, notes}' "$DATA_FILE"
            ;;
        *)
            echo "Usage: $0 [check|add|gift|list]"
            echo "  check - Run daily birthday check"
            echo "  add 'Name' 'Relationship' 'MM-DD' 'Notes' - Add new person"
            echo "  gift 'Name' 'Gift description' [year] - Log a gift given"
            echo "  list - Show all tracked birthdays"
            ;;
    esac
}

main "$@"