import { keyboardRegistry } from "../keyboard-registry"
import { instances, activeInstanceId, setActiveInstanceId } from "../../stores/instances"
import { getSessionFamily, activeSessionId, setActiveSession, activeParentSessionId } from "../../stores/sessions"

export function registerNavigationShortcuts() {
  const isMac = () => navigator.platform.toLowerCase().includes("mac")

  const buildNavigationOrder = (instanceId: string): string[] => {
    const parentId = activeParentSessionId().get(instanceId)
    if (!parentId) return []

    const familySessions = getSessionFamily(instanceId, parentId)
    if (familySessions.length === 0) return []

    const [parentSession, ...childSessions] = familySessions
    if (!parentSession) return []

    const sortedChildren = childSessions.slice().sort((a, b) => b.time.updated - a.time.updated)

    return [parentSession.id, "info", ...sortedChildren.map((session) => session.id)]
  }

  keyboardRegistry.register({
    id: "instance-prev",
    key: "[",
    modifiers: { ctrl: !isMac(), meta: isMac() },
    handler: () => {
      const ids = Array.from(instances().keys())
      if (ids.length <= 1) return
      const current = ids.indexOf(activeInstanceId() || "")
      const prev = current <= 0 ? ids.length - 1 : current - 1
      if (ids[prev]) setActiveInstanceId(ids[prev])
    },
    description: "previous instance",
    context: "global",
  })

  keyboardRegistry.register({
    id: "instance-next",
    key: "]",
    modifiers: { ctrl: !isMac(), meta: isMac() },
    handler: () => {
      const ids = Array.from(instances().keys())
      if (ids.length <= 1) return
      const current = ids.indexOf(activeInstanceId() || "")
      const next = (current + 1) % ids.length
      if (ids[next]) setActiveInstanceId(ids[next])
    },
    description: "next instance",
    context: "global",
  })

  keyboardRegistry.register({
    id: "session-prev",
    key: "[",
    modifiers: { ctrl: !isMac(), meta: isMac(), shift: true },
    handler: () => {
      const instanceId = activeInstanceId()
      if (!instanceId) return

      const navigationIds = buildNavigationOrder(instanceId)
      if (navigationIds.length === 0) return

      const currentActiveId = activeSessionId().get(instanceId)
      let currentIndex = navigationIds.indexOf(currentActiveId || "")

      if (currentIndex === -1) {
        currentIndex = navigationIds.length - 1
      }

      const targetIndex = currentIndex <= 0 ? navigationIds.length - 1 : currentIndex - 1
      const targetSessionId = navigationIds[targetIndex]

      setActiveSession(instanceId, targetSessionId)
    },
    description: "previous session",
    context: "global",
  })

  keyboardRegistry.register({
    id: "session-next",
    key: "]",
    modifiers: { ctrl: !isMac(), meta: isMac(), shift: true },
    handler: () => {
      const instanceId = activeInstanceId()
      if (!instanceId) return

      const navigationIds = buildNavigationOrder(instanceId)
      if (navigationIds.length === 0) return

      const currentActiveId = activeSessionId().get(instanceId)
      let currentIndex = navigationIds.indexOf(currentActiveId || "")

      if (currentIndex === -1) {
        currentIndex = 0
      }

      const targetIndex = (currentIndex + 1) % navigationIds.length
      const targetSessionId = navigationIds[targetIndex]

      setActiveSession(instanceId, targetSessionId)
    },
    description: "next session",
    context: "global",
  })

  keyboardRegistry.register({
    id: "switch-to-info",
    key: "l",
    modifiers: { ctrl: !isMac(), meta: isMac(), shift: true },
    handler: () => {
      const instanceId = activeInstanceId()
      if (instanceId) setActiveSession(instanceId, "info")
    },
    description: "info tab",
    context: "global",
  })
}