//! Per-CPU plugin.

use crate::cpu_percent::cpu_percent;
use crate::fields;
use glances_core::plugin::{Field, Plugin, PluginModel, UpdateContext};
use glances_core::{Args, Config};
use serde_json::Value;

pub struct PerCpuPlugin {
    pub model: PluginModel,
}

impl PerCpuPlugin {
    pub fn new(config: &Config, args: &Args) -> Self {
        let fields = fields! {
            "cpu_number" => Field::new("CPU number"),
            "total" => Field::new("Sum of CPU percentages (except idle) for current CPU number.").unit("percent"),
            "system" => Field::new("Percent time spent in kernel space. System CPU time is the time spent running code in the Operating System kernel.").unit("percent"),
            "user" => Field::new("CPU percent time spent in user space. User CPU time is the time spent on the processor running your program's code (or code in libraries).").unit("percent"),
            "iowait" => Field::new("*(Linux)*: percent time spent by the CPU waiting for I/O operations to complete.").unit("percent"),
            "idle" => Field::new("percent of CPU used by any program. Every program or task that runs on a computer system occupies a certain amount of processing time on the CPU. If the CPU has completed all tasks it is idle.").unit("percent"),
            "irq" => Field::new("*(Linux and BSD)*: percent time spent servicing/handling hardware/software interrupts. Time servicing interrupts (hardware + software).").unit("percent"),
            "nice" => Field::new("*(Unix)*: percent time occupied by user level processes with a positive nice value. The time the CPU has spent running users' processes that are *niced*.").unit("percent"),
            "steal" => Field::new("*(Linux)*: percentage of time a virtual CPU waits for a real CPU while the hypervisor is servicing another virtual processor.").unit("percent"),
            "guest" => Field::new("*(Linux)*: percent of time spent running a virtual CPU for guest operating systems under the control of the Linux kernel.").unit("percent"),
            "guest_nice" => Field::new("*(Linux)*: percent of time spent running a niced guest (virtual CPU).").unit("percent"),
            "softirq" => Field::new("*(Linux)*: percent of time spent handling software interrupts.").unit("percent"),
            "dpc" => Field::new("*(Windows)*: percent of time spent handling deferred procedure calls.").unit("percent"),
            "interrupt" => Field::new("*(Windows)*: percent of time spent handling software interrupts.").unit("percent"),
        };
        let mut model = PluginModel::new(
            "percpu",
            fields,
            Vec::new(),
            Value::Array(Vec::new()),
            config,
            args.time.unwrap_or(2.0),
            args.disable_history,
            args.disable_config_exec,
        );
        model.set_item_key("cpu_number");
        Self { model }
    }
}

impl Plugin for PerCpuPlugin {
    fn name(&self) -> &str {
        "percpu"
    }

    fn model(&self) -> &PluginModel {
        &self.model
    }

    fn model_mut(&mut self) -> &mut PluginModel {
        &mut self.model
    }

    fn get_key(&self) -> Option<&'static str> {
        Some("cpu_number")
    }

    fn collect(&mut self, _ctx: &mut UpdateContext) -> anyhow::Result<Value> {
        let mut state = cpu_percent().lock().unwrap();
        Ok(Value::Array(state.get_percpu().to_vec()))
    }
}