import { For, Show, createEffect, createMemo, on } from "solid-js"
import { createStore } from "solid-js/store"
import { createMediaQuery } from "@solid-primitives/media"
import { useParams } from "@solidjs/router"
import { Tabs } from "@opencode-ai/ui/tabs"
import { ResizeHandle } from "@opencode-ai/ui/resize-handle"
import { IconButton } from "@opencode-ai/ui/icon-button"
import { TooltipKeybind } from "@opencode-ai/ui/tooltip"
import { DragDropProvider, DragDropSensors, DragOverlay, SortableProvider, closestCenter } from "@thisbeyond/solid-dnd"
import type { DragEvent } from "@thisbeyond/solid-dnd"
import { ConstrainDragYAxis, getDraggableId } from "@/utils/solid-dnd"

import { SortableTerminalTab } from "@/components/session"
import { Terminal } from "@/components/terminal"
import { useCommand } from "@/context/command"
import { useLanguage } from "@/context/language"
import { useLayout } from "@/context/layout"
import { useTerminal, type LocalPTY } from "@/context/terminal"
import { terminalTabLabel } from "@/pages/session/terminal-label"
import { createPresence, createSizing, focusTerminalById } from "@/pages/session/helpers"
import { getTerminalHandoff, setTerminalHandoff } from "@/pages/session/handoff"

export function TerminalPanel() {
  const params = useParams()
  const layout = useLayout()
  const terminal = useTerminal()
  const language = useLanguage()
  const command = useCommand()

  const isDesktop = createMediaQuery("(min-width: 768px)")
  const sessionKey = createMemo(() => `${params.dir}${params.id ? "/" + params.id : ""}`)
  const view = createMemo(() => layout.view(sessionKey))

  const opened = createMemo(() => view().terminal.opened())
  const open = createMemo(() => isDesktop() && opened())
  const panel = createPresence(open)
  const size = createSizing()
  const height = createMemo(() => layout.terminal.height())
  const close = () => view().terminal.close()
  let root: HTMLDivElement | undefined

  const [store, setStore] = createStore({
    autoCreated: false,
    activeDraggable: undefined as string | undefined,
  })

  createEffect(() => {
    if (!opened()) {
      setStore("autoCreated", false)
      return
    }

    if (!terminal.ready() || terminal.all().length !== 0 || store.autoCreated) return
    terminal.new()
    setStore("autoCreated", true)
  })

  createEffect(
    on(
      () => terminal.all().length,
      (count, prevCount) => {
        if (prevCount === undefined || prevCount <= 0 || count !== 0) return
        if (!opened()) return
        close()
      },
    ),
  )

  createEffect(
    on(
      () => terminal.active(),
      (activeId) => {
        if (!activeId || !panel.open()) return
        if (document.activeElement instanceof HTMLElement) {
          document.activeElement.blur()
        }
        setTimeout(() => focusTerminalById(activeId), 0)
      },
    ),
  )

  createEffect(() => {
    if (panel.open()) return
    const active = document.activeElement
    if (!(active instanceof HTMLElement)) return
    if (!root?.contains(active)) return
    active.blur()
  })

  createEffect(() => {
    const dir = params.dir
    if (!dir) return
    if (!terminal.ready()) return
    language.locale()

    setTerminalHandoff(
      dir,
      terminal.all().map((pty) =>
        terminalTabLabel({
          title: pty.title,
          titleNumber: pty.titleNumber,
          t: language.t as (key: string, vars?: Record<string, string | number | boolean>) => string,
        }),
      ),
    )
  })

  const handoff = createMemo(() => {
    const dir = params.dir
    if (!dir) return []
    return getTerminalHandoff(dir) ?? []
  })

  const all = createMemo(() => terminal.all())
  const ids = createMemo(() => all().map((pty) => pty.id))
  const byId = createMemo(() => new Map(all().map((pty) => [pty.id, { ...pty }])))

  const handleTerminalDragStart = (event: unknown) => {
    const id = getDraggableId(event)
    if (!id) return
    setStore("activeDraggable", id)
  }

  const handleTerminalDragOver = (event: DragEvent) => {
    const { draggable, droppable } = event
    if (!draggable || !droppable) return

    const terminals = terminal.all()
    const fromIndex = terminals.findIndex((t: LocalPTY) => t.id === draggable.id.toString())
    const toIndex = terminals.findIndex((t: LocalPTY) => t.id === droppable.id.toString())
    if (fromIndex !== -1 && toIndex !== -1 && fromIndex !== toIndex) {
      terminal.move(draggable.id.toString(), toIndex)
    }
  }

  const handleTerminalDragEnd = () => {
    setStore("activeDraggable", undefined)

    const activeId = terminal.active()
    if (!activeId) return
    setTimeout(() => {
      focusTerminalById(activeId)
    }, 0)
  }

  return (
    <Show when={panel.show()}>
      <div
        ref={root}
        id="terminal-panel"
        role="region"
        aria-label={language.t("terminal.title")}
        aria-hidden={!panel.open()}
        inert={!panel.open()}
        class="relative w-full shrink-0 overflow-hidden"
        classList={{
          "opacity-100": panel.open(),
          "opacity-0 pointer-events-none": !panel.open(),
          "transition-[height,opacity] duration-200 ease-[cubic-bezier(0.22,1,0.36,1)] will-change-[height] motion-reduce:transition-none":
            !size.active(),
        }}
        style={{ height: panel.open() ? `${height()}px` : "0px" }}
      >
        <div class="size-full flex flex-col border-t border-border-weak-base">
          <div onPointerDown={() => size.start()}>
            <ResizeHandle
              direction="vertical"
              size={height()}
              min={100}
              max={typeof window === "undefined" ? 1000 : window.innerHeight * 0.6}
              collapseThreshold={50}
              onResize={(next) => {
                size.touch()
                layout.terminal.resize(next)
              }}
              onCollapse={close}
            />
          </div>
          <Show
            when={terminal.ready()}
            fallback={
              <div class="flex flex-col h-full pointer-events-none">
                <div class="h-10 flex items-center gap-2 px-2 border-b border-border-weaker-base bg-background-stronger overflow-hidden">
                  <For each={handoff()}>
                    {(title) => (
                      <div class="px-2 py-1 rounded-md bg-surface-base text-14-regular text-text-weak truncate max-w-40">
                        {title}
                      </div>
                    )}
                  </For>
                  <div class="flex-1" />
                  <div class="text-text-weak pr-2">
                    {language.t("common.loading")}
                    {language.t("common.loading.ellipsis")}
                  </div>
                </div>
                <div class="flex-1 flex items-center justify-center text-text-weak">
                  {language.t("terminal.loading")}
                </div>
              </div>
            }
          >
            <DragDropProvider
              onDragStart={handleTerminalDragStart}
              onDragEnd={handleTerminalDragEnd}
              onDragOver={handleTerminalDragOver}
              collisionDetector={closestCenter}
            >
              <DragDropSensors />
              <ConstrainDragYAxis />
              <div class="flex flex-col h-full">
                <Tabs
                  variant="alt"
                  value={terminal.active()}
                  onChange={(id) => terminal.open(id)}
                  class="!h-auto !flex-none"
                >
                  <Tabs.List class="h-10 border-b border-border-weaker-base">
                    <SortableProvider ids={ids()}>
                      <For each={ids()}>
                        {(id) => (
                          <Show when={byId().get(id)}>
                            {(pty) => <SortableTerminalTab terminal={pty()} onClose={close} />}
                          </Show>
                        )}
                      </For>
                    </SortableProvider>
                    <div class="h-full flex items-center justify-center">
                      <TooltipKeybind
                        title={language.t("command.terminal.new")}
                        keybind={command.keybind("terminal.new")}
                        class="flex items-center"
                      >
                        <IconButton
                          icon="plus-small"
                          variant="ghost"
                          iconSize="large"
                          onClick={terminal.new}
                          aria-label={language.t("command.terminal.new")}
                        />
                      </TooltipKeybind>
                    </div>
                  </Tabs.List>
                </Tabs>
                <div class="flex-1 min-h-0 relative">
                  <Show when={terminal.active()} keyed>
                    {(id) => (
                      <Show when={byId().get(id)}>
                        {(pty) => (
                          <div id={`terminal-wrapper-${id}`} class="absolute inset-0">
                            <Terminal
                              pty={pty()}
                              onCleanup={terminal.update}
                              onConnectError={() => terminal.clone(id)}
                            />
                          </div>
                        )}
                      </Show>
                    )}
                  </Show>
                </div>
              </div>
              <DragOverlay>
                <Show when={store.activeDraggable}>
                  {(draggedId) => (
                    <Show when={byId().get(draggedId())}>
                      {(t) => (
                        <div class="relative p-1 h-10 flex items-center bg-background-stronger text-14-regular">
                          {terminalTabLabel({
                            title: t().title,
                            titleNumber: t().titleNumber,
                            t: language.t as (key: string, vars?: Record<string, string | number | boolean>) => string,
                          })}
                        </div>
                      )}
                    </Show>
                  )}
                </Show>
              </DragOverlay>
            </DragDropProvider>
          </Show>
        </div>
      </div>
    </Show>
  )
}
