#!/bin/bash

# CPU Power Control Script
# Provides slider-like functionality for setting CPU power limits
# Replaces the missing GUI power slider functionality

RAPL_PATH="/sys/class/powercap/intel-rapl:0"
CONSTRAINT_LONG="${RAPL_PATH}/constraint_0_power_limit_uw"
CONSTRAINT_SHORT="${RAPL_PATH}/constraint_1_power_limit_uw"

# Color codes for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

print_usage() {
    echo "CPU Power Control - Equivalent to GUI Power Slider"
    echo ""
    echo "Usage: $0 [COMMAND] [VALUE]"
    echo ""
    echo "Commands:"
    echo "  status                    Show current CPU power limits"
    echo "  set <watts>              Set both long and short term limits"
    echo "  set-long <watts>         Set long term limit only"
    echo "  set-short <watts>        Set short term limit only"
    echo "  preset <name>            Apply predefined power profile"
    echo ""
    echo "Presets:"
    echo "  dynamic                  400MHz-4.2GHz dynamic (recommended)"
    echo "  max-performance          1.6GHz-4.2GHz (high performance)"
    echo "  balanced                 400MHz-2.2GHz (battery friendly, responsive)"
    echo "  power-save               400MHz-2.0GHz (battery optimized)"
    echo "  ultra-save               400MHz-1.6GHz (extreme battery)"
    echo ""
    echo "Examples:"
    echo "  $0 status                Show current settings"
    echo "  $0 set 10               Set both limits to 10W"
    echo "  $0 preset dynamic       Dynamic scaling (800MHz-4.2GHz)"
    echo ""
}

check_permissions() {
    if [ "$EUID" -ne 0 ]; then
        echo -e "${RED}Error: This script requires root privileges${NC}"
        echo "Please run with sudo: sudo $0 $*"
        exit 1
    fi
}

check_rapl_support() {
    if [ ! -d "$RAPL_PATH" ]; then
        echo -e "${RED}Error: Intel RAPL not supported on this system${NC}"
        exit 1
    fi
}

watts_to_microwatts() {
    echo $(($1 * 1000000))
}

microwatts_to_watts() {
    echo "scale=1; $1 / 1000000" | bc -l
}

get_current_limits() {
    if [ -r "$CONSTRAINT_LONG" ] && [ -r "$CONSTRAINT_SHORT" ]; then
        LONG_UW=$(cat "$CONSTRAINT_LONG")
        SHORT_UW=$(cat "$CONSTRAINT_SHORT")
        LONG_W=$(microwatts_to_watts $LONG_UW)
        SHORT_W=$(microwatts_to_watts $SHORT_UW)
    else
        echo -e "${RED}Error: Cannot read power limit files${NC}"
        exit 1
    fi
}

get_max_limits() {
    MAX_LONG_UW=$(cat "${RAPL_PATH}/constraint_0_max_power_uw")
    MAX_SHORT_UW=$(cat "${RAPL_PATH}/constraint_1_max_power_uw")
    MAX_LONG_W=$(microwatts_to_watts $MAX_LONG_UW)
    MAX_SHORT_W=$(microwatts_to_watts $MAX_SHORT_UW)
}

show_status() {
    echo -e "${BLUE}=== CPU Power Limits Status ===${NC}"
    echo ""
    
    get_current_limits
    get_max_limits
    
    echo -e "Current Limits:"
    echo -e "  Long term (PL1):  ${GREEN}${LONG_W}W${NC}"
    echo -e "  Short term (PL2): ${GREEN}${SHORT_W}W${NC}"
    echo ""
    echo -e "Maximum Limits:"
    echo -e "  Long term max:    ${YELLOW}${MAX_LONG_W}W${NC}"
    echo -e "  Short term max:   ${YELLOW}${MAX_SHORT_W}W${NC}"
    echo ""
    
    # Show platform profile
    if [ -r "/sys/firmware/acpi/platform_profile" ]; then
        PLATFORM_PROFILE=$(cat /sys/firmware/acpi/platform_profile)
        echo -e "Platform Profile: ${GREEN}${PLATFORM_PROFILE}${NC}"
    fi
    
    # Show CPU performance percentage
    if [ -r "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
        MIN_PERF=$(cat /sys/devices/system/cpu/intel_pstate/min_perf_pct)
        MAX_PERF=$(cat /sys/devices/system/cpu/intel_pstate/max_perf_pct)
        echo -e "CPU Performance: ${GREEN}${MIN_PERF}% - ${MAX_PERF}%${NC}"
    fi
    
    # Show current CPU frequency
    if [ -r "/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq" ]; then
        CUR_FREQ=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq)
        CUR_FREQ_MHZ=$((CUR_FREQ / 1000))
        MAX_FREQ=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq)
        MAX_FREQ_MHZ=$((MAX_FREQ / 1000))
        echo -e "Current CPU frequency: ${GREEN}${CUR_FREQ_MHZ} MHz${NC} (max: ${MAX_FREQ_MHZ} MHz)"
    fi
    
    # Show governor
    if [ -r "/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor" ]; then
        GOVERNOR=$(cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor)
        echo -e "CPU Governor: ${GREEN}${GOVERNOR}${NC}"
    fi
    
    # Show power usage if available
    if command -v powertop >/dev/null 2>&1; then
        echo ""
        echo -e "${BLUE}Tip: Run 'sudo powertop' to monitor real-time power consumption${NC}"
    fi
}

set_power_limit() {
    local watts=$1
    local type=$2
    
    if [ -z "$watts" ]; then
        echo -e "${RED}Error: Power value required${NC}"
        exit 1
    fi
    
    # Validate input is a number
    if ! [[ "$watts" =~ ^[0-9]+\.?[0-9]*$ ]]; then
        echo -e "${RED}Error: Invalid power value '$watts'. Must be a number.${NC}"
        exit 1
    fi
    
    local microwatts=$(watts_to_microwatts $watts)
    get_max_limits
    
    # Check against maximum limits
    case $type in
        "long")
            if [ $microwatts -gt $MAX_LONG_UW ]; then
                echo -e "${YELLOW}Warning: ${watts}W exceeds maximum long term limit of ${MAX_LONG_W}W${NC}"
                echo -e "Setting to maximum: ${MAX_LONG_W}W"
                microwatts=$MAX_LONG_UW
            fi
            echo $microwatts > "$CONSTRAINT_LONG"
            echo -e "${GREEN}Long term power limit set to $(microwatts_to_watts $microwatts)W${NC}"
            ;;
        "short")
            if [ $microwatts -gt $MAX_SHORT_UW ]; then
                echo -e "${YELLOW}Warning: ${watts}W exceeds maximum short term limit of ${MAX_SHORT_W}W${NC}"
                echo -e "Setting to maximum: ${MAX_SHORT_W}W"
                microwatts=$MAX_SHORT_UW
            fi
            echo $microwatts > "$CONSTRAINT_SHORT"
            echo -e "${GREEN}Short term power limit set to $(microwatts_to_watts $microwatts)W${NC}"
            ;;
        "both")
            # For setting both, use appropriate limits
            echo $microwatts > "$CONSTRAINT_LONG"
            
            # Short term should be higher, but not exceed max
            local short_microwatts=$((microwatts * 3 / 2))  # 1.5x long term
            if [ $short_microwatts -gt $MAX_SHORT_UW ]; then
                short_microwatts=$MAX_SHORT_UW
            fi
            echo $short_microwatts > "$CONSTRAINT_SHORT"
            
            echo -e "${GREEN}Power limits set:${NC}"
            echo -e "  Long term:  $(microwatts_to_watts $microwatts)W"
            echo -e "  Short term: $(microwatts_to_watts $short_microwatts)W"
            ;;
    esac
}

apply_preset() {
    local preset=$1
    
    case $preset in
        "dynamic")
            # Full dynamic range: 400MHz to 4.2GHz
            set_power_limit 15 long
            set_power_limit 25 short
            # Set platform profile to balanced for dynamic scaling
            if [ -w "/sys/firmware/acpi/platform_profile" ]; then
                echo "balanced" > /sys/firmware/acpi/platform_profile 2>/dev/null
                echo -e "${BLUE}Platform profile: balanced${NC}"
            fi
            # Allow full range 0-100%
            if [ -w "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
                echo 0 > /sys/devices/system/cpu/intel_pstate/min_perf_pct
                echo -e "${BLUE}CPU Performance: 0% - 100% (400MHz - 4.2GHz)${NC}"
            fi
            # Set governor to powersave for dynamic scaling
            for gov in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
                echo "powersave" > $gov 2>/dev/null
            done
            # Set energy preference to balance_performance
            for epp in /sys/devices/system/cpu/cpu*/cpufreq/energy_performance_preference; do
                echo "balance_performance" > $epp 2>/dev/null
            done
            echo -e "${GREEN}Applied dynamic scaling preset (recommended)${NC}"
            ;;
        "max-performance")
            # Higher base but still allows boost: 1.6GHz to 4.2GHz
            set_power_limit 15 long
            set_power_limit 25 short
            # Set platform profile to performance
            if [ -w "/sys/firmware/acpi/platform_profile" ]; then
                echo "performance" > /sys/firmware/acpi/platform_profile 2>/dev/null
                echo -e "${BLUE}Platform profile: performance${NC}"
            fi
            # Set minimum to base frequency (38% = 1.6GHz)
            if [ -w "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
                echo 38 > /sys/devices/system/cpu/intel_pstate/min_perf_pct
                echo -e "${BLUE}CPU Performance: 38% - 100% (1.6GHz - 4.2GHz)${NC}"
            fi
            # Set governor to powersave (still allows turbo with intel_pstate)
            for gov in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
                echo "powersave" > $gov 2>/dev/null
            done
            # Set energy preference to performance
            for epp in /sys/devices/system/cpu/cpu*/cpufreq/energy_performance_preference; do
                echo "performance" > $epp 2>/dev/null
            done
            echo -e "${GREEN}Applied maximum performance preset${NC}"
            ;;
        "balanced")
            set_power_limit 10 long
            set_power_limit 15 short
            # Set platform profile to balanced
            if [ -w "/sys/firmware/acpi/platform_profile" ]; then
                echo "balanced" > /sys/firmware/acpi/platform_profile 2>/dev/null
                echo -e "${BLUE}Platform profile: balanced${NC}"
            fi
            # Allow dynamic scaling 0-52% (400MHz - 2.2GHz)
            if [ -w "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
                echo 0 > /sys/devices/system/cpu/intel_pstate/min_perf_pct
                echo -e "${BLUE}CPU Performance: 0% - 52% (400MHz - 2.2GHz)${NC}"
            fi
            if [ -w "/sys/devices/system/cpu/intel_pstate/max_perf_pct" ]; then
                echo 52 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
            fi
            # Set max frequency to 2.2 GHz
            for freq in /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq; do
                echo 2200000 > $freq 2>/dev/null
            done
            # Set governor to powersave
            for gov in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
                echo "powersave" > $gov 2>/dev/null
            done
            # Set energy preference to balance_power
            for epp in /sys/devices/system/cpu/cpu*/cpufreq/energy_performance_preference; do
                echo "balance_power" > $epp 2>/dev/null
            done
            echo -e "${GREEN}Applied balanced preset (battery friendly)${NC}"
            ;;
        "power-save")
            set_power_limit 8 long
            set_power_limit 12 short
            # Set platform profile to low-power
            if [ -w "/sys/firmware/acpi/platform_profile" ]; then
                echo "low-power" > /sys/firmware/acpi/platform_profile 2>/dev/null
                echo -e "${BLUE}Platform profile: low-power${NC}"
            fi
            # Limit to 50% max performance
            if [ -w "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
                echo 0 > /sys/devices/system/cpu/intel_pstate/min_perf_pct
                echo -e "${BLUE}CPU Performance: 0% - 50% (800MHz - 2.0GHz)${NC}"
            fi
            if [ -w "/sys/devices/system/cpu/intel_pstate/max_perf_pct" ]; then
                echo 50 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
            fi
            # Set energy preference to power
            for epp in /sys/devices/system/cpu/cpu*/cpufreq/energy_performance_preference; do
                echo "power" > $epp 2>/dev/null
            done
            echo -e "${GREEN}Applied power-saving preset${NC}"
            ;;
        "ultra-save")
            set_power_limit 6 long
            set_power_limit 8 short
            # Set platform profile to low-power
            if [ -w "/sys/firmware/acpi/platform_profile" ]; then
                echo "low-power" > /sys/firmware/acpi/platform_profile 2>/dev/null
                echo -e "${BLUE}Platform profile: low-power${NC}"
            fi
            # Limit to base frequency (38% = 1.6GHz max)
            if [ -w "/sys/devices/system/cpu/intel_pstate/min_perf_pct" ]; then
                echo 0 > /sys/devices/system/cpu/intel_pstate/min_perf_pct
                echo -e "${BLUE}CPU Performance: 0% - 38% (800MHz - 1.6GHz)${NC}"
            fi
            if [ -w "/sys/devices/system/cpu/intel_pstate/max_perf_pct" ]; then
                echo 38 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
            fi
            # Set energy preference to power
            for epp in /sys/devices/system/cpu/cpu*/cpufreq/energy_performance_preference; do
                echo "power" > $epp 2>/dev/null
            done
            echo -e "${GREEN}Applied ultra power-saving preset${NC}"
            ;;
        *)
            echo -e "${RED}Error: Unknown preset '$preset'${NC}"
            echo "Available presets: dynamic, max-performance, balanced, power-save, ultra-save"
            exit 1
            ;;
    esac
}

# Main script logic
case "$1" in
    "status")
        check_rapl_support
        show_status
        ;;
    "set")
        check_permissions
        check_rapl_support
        set_power_limit "$2" "both"
        ;;
    "set-long")
        check_permissions
        check_rapl_support
        set_power_limit "$2" "long"
        ;;
    "set-short")
        check_permissions
        check_rapl_support
        set_power_limit "$2" "short"
        ;;
    "preset")
        check_permissions
        check_rapl_support
        apply_preset "$2"
        ;;
    *)
        print_usage
        ;;
esac