package tui

import (
    "fmt"
    "log"
    "sync"
    "strconv"
    "strings"
    "time"
    "FRMS/internal/pkg/logging"
    "github.com/rivo/tview"
    _ "github.com/gdamore/tcell/v2"
    "os"
)

type Device struct {
    Id uint32
    Type string
    Status string
    Data string
    Index uint32
}

type TUI struct {
    *Display
    *TUIClient
    SelectedReactor <-chan uint32
    SelectedDevice <-chan uint32
    Err chan error
}

func NewTUI(ip string, port int, ifconfig string, ch chan error) *TUI {
    t := &TUI{}
    t.Err = ch
    client := NewTUIClient(ip, port, ifconfig)
    t.TUIClient = client
    return t
}

func (t *TUI) Start() {
    // setup tview app and wait for user connection in standin modal
    if err := t.TUIClient.Start(); err != nil {
        t.Err <- err
    }
    logging.Debug(logging.DStart, "TUI %v starting", t.Id)
    go t.Monitor()
    t.CreateDisplay()
    t.Display.Start()
}

func (t *TUI) CreateDisplay() {
    rc := make(chan uint32)
    dc := make(chan uint32)
    t.Display = NewDisplay(rc,dc)
    t.SelectedReactor = rc
    t.SelectedDevice = dc
    t.Flex.AddItem(t.ReactorList,0,1,true).
    AddItem(t.DeviceList,0,2,false)
}

func (t *TUI) Monitor() {
    // orchestrates updates and grpc requests
    timer := make(chan struct{})
    go func(signal chan struct{}){
        for {
            signal <- struct{}{}
            time.Sleep(1 * time.Second)
        }
    }(timer)

    for {
        select {
        case reactor := <-t.SelectedReactor:
            // reactor has been selected in tui, grabbing devs
            t.App.QueueUpdateDraw(func() {
                t.UpdateDevices(reactor)
            })
            logging.Debug(logging.DClient, "%v getting reactor devices", t.Id)
        case dev := <-t.SelectedDevice:
            logging.Debug(logging.DClient, "%v editing device %v", t.Id, dev)
            // TODO
        case <-timer:
            // time to ping for status
            logging.Debug(logging.DClient, "%v pinging for updates", t.Id)
            t.App.QueueUpdateDraw(func() {
                t.UpdateDevices()
            })
        }
    }
}

func (t *TUI) UpdateDevices(r ...uint32) {
    // get devices for the reactor and update the tui
    // see if there is a page being displayed
    // overwrite if called as a func
    var devs map[uint32]*Device
    var err error
    if len(r) > 0 {
        // could be a reactor id or 1 for update reactors
        if r[0] != 0 {
            t.Display.DeviceList.Clear()
        } else {
            t.ReactorList.Clear()
            t.ReactorList.AddItem("Refresh","Press (r) to refresh manually", 114, nil)
            t.ReactorList.AddItem("Quit","Press (q) to quit",113,func() {
                t.App.Stop()
                os.Exit(0)
            })
        }
        devs, err = t.TUIClient.GetDevices(r[0])
    } else {
        devs, err = t.TUIClient.GetDevices()
    }
    if err != nil {
        log.Fatal(err)
    }
    //if id != 0 {
    // split based on type to simplify update
    reactors := make(map[uint32]*Device)
    devices := make(map[uint32]*Device)
    for id, dev := range devs {
        if dev.Type == "Reactor" {
            reactors[id] = dev
        } else {
            devices[id] = dev
        }
    }
    t.DisplayDevices(devices)
    t.DisplayReactors(reactors)
}

// display struct and logic
type Display struct {
    App *tview.Application
    Flex *tview.Flex
    ReactorList *tview.List
    DeviceList *tview.List
    SelectedReactor chan<- uint32
    SelectedDevice chan<- uint32
    sync.Mutex
}

func NewDisplay(rc,dc chan uint32) *Display {
    d := &Display{}
    d.App = tview.NewApplication()
    d.Flex = tview.NewFlex()
    d.DeviceList = tview.NewList()
    d.ReactorList = tview.NewList()
    d.ReactorList.AddItem("Refresh","Press (r) to refresh manually", 114, nil)
    d.ReactorList.AddItem("Quit","Press (q) to quit",113,func() {
        d.App.Stop()
        os.Exit(0)
    })
    d.ReactorList.SetTitle("Reactors").SetBorder(true)
    d.ReactorList.SetSelectedFunc(d.SelectReactor)
    d.DeviceList.SetTitle("Devices").SetBorder(true)
    d.DeviceList.SetSelectedFunc(d.SelectDevice)
    d.SelectedReactor = rc
    d.SelectedDevice = dc
    return d
}

func (d *Display) Start() {
    if err := d.App.SetRoot(d.Flex, true).Run(); err != nil {
        d.App.Stop()
        log.Fatal(err)
    }
}

func (d *Display) DisplayReactors(r map[uint32]*Device) {
    // this func takes in a list of devices to update and loops over them
    // works by padding list for entries not seen yet
    for _, reactor := range r {
        txt := fmt.Sprintf("%v %v", reactor.Id, reactor.Status)
        indx := int(reactor.Index)
        for indx + 2 >= d.ReactorList.GetItemCount() {
            // this prevent overwriting quit entry
            d.ReactorList.InsertItem(-3,txt,reactor.Data,rune(47+d.ReactorList.GetItemCount()),nil)
        }
        if indx + 2 < d.ReactorList.GetItemCount() {
            d.ReactorList.SetItemText(indx,txt,reactor.Data)
        }
    }
}

func (d *Display) DisplayDevices(devs map[uint32]*Device) {
    // going to just clear every time as we reload new dev lists anyway
    // going to clear on every reactor selection to simplify
    // can probably just load from SM to save system resources on spam reloading
    for _, dev := range devs {
        txt := fmt.Sprintf("0x%x %v %v",dev.Id,dev.Status,dev.Type)
        indx := int(dev.Index)
        for indx >= d.DeviceList.GetItemCount() {
            d.DeviceList.AddItem(txt,dev.Data,rune(49+d.DeviceList.GetItemCount()), nil)
        }
        if indx < d.DeviceList.GetItemCount() {
            d.DeviceList.SetItemText(indx,txt,dev.Data)
        }
    }
}

func (d *Display) SelectReactor(index int, main, data string, r rune) {
    // called when reactor in list in selected
    if main != "Quit" {
        if main == "Refresh" {
            // TODO
        } else {
            maintxt := strings.Split(main," ")
            id := maintxt[0]
            if id, err := strconv.ParseUint(id, 10, 32); err != nil {
                log.Fatal(err)
            } else {
                d.SelectedReactor <-uint32(id)
            }
        }
    }
}

func (d *Display) SelectDevice(index int, main, data string, r rune) {
    // called when device is selected in sub menu
    maintxt := strings.Split(main," ")
    id := maintxt[0]
    id = strings.Trim(id,"0x \n")
    logging.Debug(logging.DClient,"Selected dev %v", id)
    if id, err := strconv.ParseUint(id, 16, 32); err != nil {
        logging.Debug(logging.DError, "Error parsing: %v", err)
        os.Exit(1)
    } else {
        d.SelectedDevice <-uint32(id)
    }
}