/**
 * Keyboard routing.
 *
 * The bindings are carried over verbatim from the Bubble Tea version — vim
 * motions alongside the arrows, shifted HJKL to resize a tile, `q` meaning
 * "quality" inside the editor but "quit" at the menu — so existing muscle
 * memory keeps working. `S` saves from anywhere, which is new.
 *
 * Matching is on `key.sequence` for printable keys because it preserves case
 * (`key.name` reports "l" for both `l` and `L`, which would collapse "move
 * right" into "make wider"), and on `key.name` for the named keys.
 */

import type { KeyEvent } from "@opentui/core"
import type { Store } from "./state.ts"

/** What the key handler needs from the UI: menu activation. */
export interface MenuActivator {
  activateMenu(idx: number): void
}

export function handleKey(store: Store, ui: MenuActivator, key: KeyEvent): void {
  // Ignore input while a discover or save is in flight, rather than queueing
  // keys that would act on state the bridge call is about to replace.
  if (store.busy) return

  const name = key.name
  const seq = key.sequence
  const back = name === "escape" || name === "backspace"

  switch (store.screen) {
    case "menu": {
      const n = store.listLength()
      if (name === "up" || seq === "k") store.moveCursor(-1, n)
      else if (name === "down" || seq === "j") store.moveCursor(1, n)
      else if (name === "return" || name === "space" || seq === "l") ui.activateMenu(store.cursor)
      else if (seq === "q") store.requestQuit()
      else if (seq === "S") void store.save()
      return
    }

    case "cameras": {
      const n = store.listLength()
      if (back || seq === "h") store.go("menu")
      else if (name === "up" || seq === "k") store.moveCursor(-1, n)
      else if (name === "down" || seq === "j") store.moveCursor(1, n)
      else if (seq === "d") store.toggleCameraDisabled()
      else if (seq === "x") store.deleteCamera()
      else if (seq === "S") void store.save()
      return
    }

    case "layouts": {
      const n = store.listLength()
      if (back || seq === "h") store.go("menu")
      else if (name === "up" || seq === "k") store.moveCursor(-1, n)
      else if (name === "down" || seq === "j") store.moveCursor(1, n)
      else if (name === "return" || seq === "l") store.openEditor(store.cursor)
      else if (seq === "S") void store.save()
      return
    }

    case "setActive": {
      const n = store.listLength()
      if (back || seq === "h") store.go("menu")
      else if (name === "up" || seq === "k") store.moveCursor(-1, n)
      else if (name === "down" || seq === "j") store.moveCursor(1, n)
      else if (name === "return" || seq === "l") store.setActiveLayout(store.cursor)
      return
    }

    case "cameraPicker": {
      const n = store.listLength()
      if (back || seq === "h") store.go("layoutEdit")
      else if (name === "up" || seq === "k") store.moveCursor(-1, n)
      else if (name === "down" || seq === "j") store.moveCursor(1, n)
      else if (name === "return" || seq === "l") store.choosePickerOption(store.cursor)
      return
    }

    case "layoutEdit": {
      // Returning to the layout list puts the cursor back on the layout that
      // was being edited, not at the top.
      if (back) store.go("layouts", store.editLayout)
      else if (name === "up" || seq === "k") store.moveCell(0, -1)
      else if (name === "down" || seq === "j") store.moveCell(0, 1)
      else if (name === "left" || seq === "h") store.moveCell(-1, 0)
      else if (name === "right" || seq === "l") store.moveCell(1, 0)
      else if (name === "return" || name === "space" || seq === "a") store.go("cameraPicker")
      else if (seq === "c") store.clearAt()
      else if (seq === "q") store.cycleQuality()
      // Shifted motions resize the tile; unshifted move the cursor.
      else if (seq === "L") store.resizeTile(1, 0)
      else if (seq === "H") store.resizeTile(-1, 0)
      else if (seq === "J") store.resizeTile(0, 1)
      else if (seq === "K") store.resizeTile(0, -1)
      else if (seq === "]") store.resizeGrid(1, 0)
      else if (seq === "[") store.resizeGrid(-1, 0)
      else if (seq === "}") store.resizeGrid(0, 1)
      else if (seq === "{") store.resizeGrid(0, -1)
      else if (seq === "S") void store.save()
      return
    }
  }
}