import QtQuick
import Quickshell
import Quickshell.Io
pragma Singleton
pragma ComponentBehavior: Bound

Singleton {
    id: root
    
    property list<var> ddcMonitors: []
    readonly property list<Monitor> monitors: variants.instances
    property bool brightnessAvailable: laptopBacklightAvailable || ddcMonitors.length > 0
    property bool laptopBacklightAvailable: false
    property int brightnessLevel: 75
    property int laptopBrightnessLevel: 75
    
    function getMonitorForScreen(screen: ShellScreen): var {
        return monitors.find(function(m) { return m.modelData === screen; });
    }
    
    property var debounceTimer: Timer {
        id: debounceTimer
        interval: 50
        repeat: false
        property int pendingValue: 0
        onTriggered: {
            const focusedMonitor = monitors.find(function(m) { return m.modelData === Quickshell.screens[0]; });
            if (focusedMonitor) {
                focusedMonitor.setBrightness(pendingValue / 100);
            }
        }
    }
    
    property var laptopDebounceTimer: Timer {
        id: laptopDebounceTimer
        interval: 50
        repeat: false
        property int pendingValue: 0
        onTriggered: {
            laptopBrightnessProcess.command = ["brightnessctl", "set", pendingValue + "%"];
            laptopBrightnessProcess.running = true;
        }
    }
    
    function setBrightness(percentage) {
        if (root.laptopBacklightAvailable) {
            // Use laptop backlight control
            root.laptopBrightnessLevel = percentage;
            laptopDebounceTimer.pendingValue = percentage;
            laptopDebounceTimer.restart();
        } else {
            // Use external monitor control
            root.brightnessLevel = percentage;
            debounceTimer.pendingValue = percentage;
            debounceTimer.restart();
        }
    }
    
    function increaseBrightness(): void {
        if (root.laptopBacklightAvailable) {
            setBrightness(Math.min(100, root.laptopBrightnessLevel + 10));
        } else {
            const focusedMonitor = monitors.find(function(m) { return m.modelData === Quickshell.screens[0]; });
            if (focusedMonitor)
                focusedMonitor.setBrightness(focusedMonitor.brightness + 0.1);
        }
    }
    
    function decreaseBrightness(): void {
        if (root.laptopBacklightAvailable) {
            setBrightness(Math.max(1, root.laptopBrightnessLevel - 10));
        } else {
            const focusedMonitor = monitors.find(function(m) { return m.modelData === Quickshell.screens[0]; });
            if (focusedMonitor)
                focusedMonitor.setBrightness(focusedMonitor.brightness - 0.1);
        }
    }
    
    onMonitorsChanged: {
        ddcMonitors = [];
        if (root.brightnessAvailable) {
            ddcProc.running = true;
        }
        
        // Update brightness level from laptop or first monitor
        if (root.laptopBacklightAvailable) {
            // Laptop brightness is already set by laptopBrightnessInitProcess
        } else if (monitors.length > 0) {
            root.brightnessLevel = Math.round(monitors[0].brightness * 100);
        }
    }
    
    Component.onCompleted: {
        ddcAvailabilityChecker.running = true;
        laptopBacklightChecker.running = true;
    }
    
    Variants {
        id: variants
        model: Quickshell.screens
        Monitor {}
    }
    
    Process {
        id: ddcAvailabilityChecker
        command: ["which", "ddcutil"]
        onExited: function(exitCode) {
            root.brightnessAvailable = (exitCode === 0);
            if (root.brightnessAvailable) {
                ddcProc.running = true;
            }
        }
    }
    
    Process {
        id: laptopBacklightChecker
        command: ["brightnessctl", "--list"]
        onExited: function(exitCode) {
            root.laptopBacklightAvailable = (exitCode === 0);
            if (root.laptopBacklightAvailable) {
                laptopBrightnessInitProcess.running = true;
            }
        }
    }
    
    Process {
        id: laptopBrightnessProcess
        running: false
        
        onExited: function(exitCode) {
            if (exitCode === 0) {
                // Update was successful
                root.brightnessLevel = root.laptopBrightnessLevel;
            } else {
                console.warn("Failed to set laptop brightness, exit code:", exitCode);
            }
        }
    }
    
    Process {
        id: laptopBrightnessInitProcess
        command: ["brightnessctl", "get"]
        running: false
        
        stdout: StdioCollector {
            onStreamFinished: {
                if (text.trim()) {
                    // Get max brightness to calculate percentage
                    laptopMaxBrightnessProcess.running = true;
                    root.laptopBrightnessLevel = parseInt(text.trim());
                }
            }
        }
        
        onExited: function(exitCode) {
            if (exitCode !== 0) {
                console.warn("Failed to get laptop brightness, exit code:", exitCode);
            }
        }
    }
    
    Process {
        id: laptopMaxBrightnessProcess
        command: ["brightnessctl", "max"]
        running: false
        
        stdout: StdioCollector {
            onStreamFinished: {
                if (text.trim()) {
                    const maxBrightness = parseInt(text.trim());
                    const currentPercentage = Math.round((root.laptopBrightnessLevel / maxBrightness) * 100);
                    root.laptopBrightnessLevel = currentPercentage;
                    root.brightnessLevel = currentPercentage;
                }
            }
        }
        
        onExited: function(exitCode) {
            if (exitCode !== 0) {
                console.warn("Failed to get max laptop brightness, exit code:", exitCode);
            }
        }
    }
    
    Process {
        id: ddcProc
        command: ["ddcutil", "detect", "--brief"]
        running: false
        stdout: StdioCollector {
            onStreamFinished: {
                if (text.trim()) {
                    root.ddcMonitors = text.trim().split("\n\n").filter(function(d) { return d.startsWith("Display "); }).map(function(d) { return ({
                        model: d.match(/Monitor:.*:(.*):.*/)?.[1] || "Unknown",
                        busNum: d.match(/I2C bus:[ ]*\/dev\/i2c-([0-9]+)/)?.[1] || "0"
                    }); });
                } else {
                    root.ddcMonitors = [];
                }
            }
        }
        onExited: function(exitCode) {
            if (exitCode !== 0) {
                root.ddcMonitors = [];
            }
        }
    }
    
    component Monitor: QtObject {
        id: monitor
        
        required property ShellScreen modelData
        readonly property bool isDdc: root.ddcMonitors.some(function(m) { return m.model === modelData.model; })
        readonly property string busNum: root.ddcMonitors.find(function(m) { return m.model === modelData.model; })?.busNum ?? ""
        property real brightness: 0.75
        
        readonly property Process initProc: Process {
            stdout: StdioCollector {
                onStreamFinished: {
                    if (text.trim()) {
                        const parts = text.trim().split(" ");
                        if (parts.length >= 5) {
                            const current = parseInt(parts[3]) || 75;
                            const max = parseInt(parts[4]) || 100;
                            monitor.brightness = current / max;
                            root.brightnessLevel = Math.round(monitor.brightness * 100);
                        }
                    }
                }
            }
            onExited: function(exitCode) {
                if (exitCode !== 0) {
                    monitor.brightness = 0.75;
                    root.brightnessLevel = 75;
                }
            }
        }
        
        function setBrightness(value: real): void {
            value = Math.max(0, Math.min(1, value));
            const rounded = Math.round(value * 100);
            if (Math.round(brightness * 100) === rounded)
                return;
            
            brightness = value;
            root.brightnessLevel = rounded;
            
            if (isDdc && busNum) {
                Quickshell.execDetached(["ddcutil", "-b", busNum, "setvcp", "10", rounded.toString()]);
            }
        }
        
        onBusNumChanged: {
            if (isDdc && busNum) {
                initProc.command = ["ddcutil", "-b", busNum, "getvcp", "10", "--brief"];
                initProc.running = true;
            }
        }
        
        Component.onCompleted: {
            Qt.callLater(function() {
                if (isDdc && busNum) {
                    initProc.command = ["ddcutil", "-b", busNum, "getvcp", "10", "--brief"];
                    initProc.running = true;
                }
            });
        }
    }
}