package gui

import (
	"fmt"
	"sort"
	"strings"
	"time"

	"gioui.org/layout"
	"gioui.org/unit"
	"gioui.org/widget/material"
	"vpn-client/internal/config"
	"vpn-client/internal/vless"
	"vpn-client/internal/wireguard"
)

func (u *ui) addWireGuardManual() {
	name := strings.TrimSpace(u.wgNameEditor.Text())
	configText := strings.TrimSpace(u.wgConfigEditor.Text())
	if name == "" || configText == "" {
		u.message = "WireGuard name and config text are required."
		u.messageColor = dangerColor
		return
	}
	if err := wireguard.AddConfig(name, configText); err != nil {
		u.message = err.Error()
		u.messageColor = dangerColor
		return
	}
	u.wgNameEditor.SetText("")
	u.wgConfigEditor.SetText("")
	u.message = "WireGuard config added."
	u.messageColor = successColor
	u.refresh()
}

func (u *ui) addWireGuardFromFile() {
	name := strings.TrimSpace(u.wgFileNameEditor.Text())
	filePath := strings.TrimSpace(u.wgFilePathEditor.Text())
	if name == "" || filePath == "" {
		u.message = "WireGuard name and file path are required."
		u.messageColor = dangerColor
		return
	}
	if err := wireguard.AddConfigFromFile(name, filePath); err != nil {
		u.message = err.Error()
		u.messageColor = dangerColor
		return
	}
	u.wgFileNameEditor.SetText("")
	u.wgFilePathEditor.SetText("")
	u.message = "WireGuard config imported from file."
	u.messageColor = successColor
	u.refresh()
}

func (u *ui) deleteWireGuardConfig(name string) {
	if err := wireguard.DeleteConfig(name); err != nil {
		u.message = err.Error()
		u.messageColor = dangerColor
		return
	}
	u.message = "WireGuard config removed."
	u.messageColor = successColor
	u.refresh()
}

func (u *ui) subscriptionConfigs(name string) []config.VLESSConfig {
	items := make([]config.VLESSConfig, 0)
	for _, cfg := range u.configs.VLESS {
		if cfg.Subscription == name {
			items = append(items, cfg)
		}
	}
	return items
}

func (u *ui) subscriptionSummary(name string) string {
	items := u.subscriptionConfigs(name)
	if len(items) == 0 {
		return "No imported configs yet."
	}
	preview := strings.TrimPrefix(items[0].Name, fmt.Sprintf("[%s] ", name))
	if len(items) == 1 {
		return fmt.Sprintf("1 imported config: %s", trimForPreview(preview, 42))
	}
	return fmt.Sprintf("%d imported configs. First: %s", len(items), trimForPreview(preview, 36))
}

func (u *ui) testSubscriptionConfigs(name string) error {
	items := u.subscriptionConfigs(name)
	if len(items) == 0 {
		return fmt.Errorf("no imported configs found for %s", name)
	}

	type result struct {
		name string
		ping float64
		ok   bool
	}
	results := make([]result, 0, len(items))
	for _, cfg := range items {
		ok, ping, _ := vless.PingServer(cfg.URL, 3*time.Second)
		results = append(results, result{
			name: strings.TrimPrefix(cfg.Name, fmt.Sprintf("[%s] ", name)),
			ping: ping,
			ok:   ok,
		})
	}

	successful := results[:0]
	for _, r := range results {
		if r.ok {
			successful = append(successful, r)
		}
	}
	if len(successful) == 0 {
		return fmt.Errorf("all %d configs from %s are unreachable", len(results), name)
	}

	sort.Slice(successful, func(i, j int) bool { return successful[i].ping < successful[j].ping })
	best := successful[0]
	u.message = fmt.Sprintf("%s: %d/%d reachable, best %s at %.0f ms.", name, len(successful), len(results), trimForPreview(best.name, 34), best.ping)
	u.messageColor = successColor
	return nil
}

func (u *ui) layoutWireGuard(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(
		gtx,
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Spacing: layout.SpaceBetween}.Layout(
				gtx,
				layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
					return u.card(gtx, panelColor, func(gtx layout.Context) layout.Dimensions {
						return layout.UniformInset(unit.Dp(18)).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Axis: layout.Vertical}.Layout(
								gtx,
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									lbl := material.H5(u.theme, "Add manually")
									lbl.Color = textColor
									return lbl.Layout(gtx)
								}),
								layout.Rigid(spacerH(10)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions { return u.layoutEditor(gtx, &u.wgNameEditor, "Config name") }),
								layout.Rigid(spacerH(10)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return u.layoutEditor(gtx, &u.wgConfigEditor, "WireGuard config text")
								}),
								layout.Rigid(spacerH(12)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return u.layoutButton(gtx, &u.addWGManualBtn, "Save manual config", accentColor)
								}),
							)
						})
					})
				}),
				layout.Rigid(spacerW(12)),
				layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
					return u.card(gtx, panelColor, func(gtx layout.Context) layout.Dimensions {
						return layout.UniformInset(unit.Dp(18)).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Axis: layout.Vertical}.Layout(
								gtx,
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									lbl := material.H5(u.theme, "Import from file")
									lbl.Color = textColor
									return lbl.Layout(gtx)
								}),
								layout.Rigid(spacerH(10)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return u.layoutEditor(gtx, &u.wgFileNameEditor, "Config name")
								}),
								layout.Rigid(spacerH(10)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return u.layoutEditor(gtx, &u.wgFilePathEditor, "Path to .conf file")
								}),
								layout.Rigid(spacerH(12)),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return u.layoutButton(gtx, &u.addWGFileBtn, "Import file", accentSoftColor)
								}),
							)
						})
					})
				}),
			)
		}),
		layout.Rigid(spacerH(16)),
		layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
			return u.card(gtx, panelColor, func(gtx layout.Context) layout.Dimensions {
				return layout.UniformInset(unit.Dp(18)).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					if len(u.configs.WireGuard) == 0 {
						lbl := material.Body1(u.theme, "No WireGuard configs yet.")
						lbl.Color = mutedColor
						return lbl.Layout(gtx)
					}
					return u.wgList.Layout(gtx, len(u.configs.WireGuard), func(gtx layout.Context, i int) layout.Dimensions {
						cfg := u.configs.WireGuard[i]
						return layout.Inset{Bottom: unit.Dp(12)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
							return u.card(gtx, panelAltColor, func(gtx layout.Context) layout.Dimensions {
								return layout.UniformInset(unit.Dp(16)).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
									return layout.Flex{Axis: layout.Vertical}.Layout(
										gtx,
										layout.Rigid(func(gtx layout.Context) layout.Dimensions {
											lbl := material.H6(u.theme, cfg.Name)
											lbl.Color = textColor
											return lbl.Layout(gtx)
										}),
										layout.Rigid(func(gtx layout.Context) layout.Dimensions {
											meta := material.Body2(u.theme, trimForPreview(cfg.Config, 110))
											meta.Color = mutedColor
											return meta.Layout(gtx)
										}),
										layout.Rigid(spacerH(12)),
										layout.Rigid(func(gtx layout.Context) layout.Dimensions {
											return layout.Flex{}.Layout(
												gtx,
												layout.Rigid(func(gtx layout.Context) layout.Dimensions {
													return u.layoutButton(gtx, &u.wgConnectBtns[i], "Connect", accentColor)
												}),
												layout.Rigid(spacerW(8)),
												layout.Rigid(func(gtx layout.Context) layout.Dimensions {
													return u.layoutButton(gtx, &u.wgDeleteBtns[i], "Delete", dangerColor)
												}),
											)
										}),
									)
								})
							})
						})
					})
				})
			})
		}),
	)
}