import type { Command } from "commander"
import * as vm from "../vm.ts"
import * as git from "../git.ts"
import * as state from "../state.ts"
import { spinner } from "../spinner.ts"
import { reset, dim, green, yellow, cyan, red } from "../fmt.ts"

export function register(program: Command) {
  const vmCmd = program.command("vm").description("Manage the sandlot VM")

  vmCmd
    .command("create")
    .description("Create and provision the VM")
    .action(async () => {
      const spin = spinner("Creating VM")
      try {
        await vm.create((msg) => { spin.text = msg })
        spin.succeed("VM created")
      } catch (err) {
        spin.fail(String((err as Error).message ?? err))
        process.exit(1)
      }
    })

  vmCmd
    .command("start")
    .description("Start the VM")
    .action(async () => {
      try {
        await vm.start()
        console.log("✔ VM started")
      } catch (err) {
        console.error(`✖ ${(err as Error).message ?? err}`)
        process.exit(1)
      }
    })

  vmCmd
    .command("shell")
    .description("Open a shell in the VM")
    .action(async () => {
      await vm.ensure()
      await vm.shell()
    })

  vmCmd
    .command("status")
    .description("Show VM status and all sessions across repos")
    .option("--json", "Output as JSON")
    .action(async (opts: { json?: boolean }) => {
      const s = await vm.status()
      const sessions = await state.loadAll()

      if (opts.json) {
        console.log(JSON.stringify({ vm: s, sessions }, null, 2))
        return
      }

      const statusColors: Record<string, string> = { running: green, stopped: yellow, missing: red }
      console.log(`${dim}VM:${reset} ${statusColors[s] ?? ""}${s}${reset}`)

      if (sessions.length === 0) {
        console.log(`\n${dim}No active sessions.${reset}`)
        return
      }

      // Determine status for each session in parallel
      const statusEntries = await Promise.all(
        sessions.map(async (sess): Promise<[string, string]> => {
          const key = `${sess.repo}/${sess.branch}`
          try {
            if (await vm.isClaudeActive(sess.worktree, sess.branch)) return [key, "active"]
            if (await git.isDirty(sess.worktree)) return [key, "dirty"]
            if (await git.hasNewCommits(sess.worktree)) return [key, "saved"]
          } catch {}
          return [key, "idle"]
        })
      )
      const statuses = Object.fromEntries(statusEntries)

      const icons: Record<string, string> = { idle: `${dim}◯${reset}`, active: `${cyan}◎${reset}`, dirty: `${yellow}◐${reset}`, saved: `${green}●${reset}` }
      const branchColors: Record<string, string> = { idle: dim, active: cyan, dirty: yellow, saved: green }

      const repoWidth = Math.max(4, ...sessions.map(sess => sess.repo.length))
      const branchWidth = Math.max(6, ...sessions.map(sess => sess.branch.length))
      const cols = process.stdout.columns || 80
      const prefixWidth = repoWidth + branchWidth + 6

      console.log(`\n  ${dim}${"REPO".padEnd(repoWidth)}  ${"BRANCH".padEnd(branchWidth)}  PROMPT${reset}`)

      for (const sess of sessions) {
        const prompt = (sess.prompt ?? "").split("\n")[0]
        const key = `${sess.repo}/${sess.branch}`
        const status = statuses[key]
        const icon = icons[status]
        const bc = branchColors[status]
        const maxPrompt = cols - prefixWidth
        const truncated = maxPrompt > 3 && prompt.length > maxPrompt ? prompt.slice(0, maxPrompt - 3) + "..." : prompt
        console.log(`${icon} ${dim}${sess.repo.padEnd(repoWidth)}${reset}  ${bc}${sess.branch.padEnd(branchWidth)}${reset}  ${dim}${truncated}${reset}`)
      }

      console.log(`\n${dim}◯ idle${reset} · ${cyan}◎ active${reset} · ${yellow}◐ unsaved${reset} · ${green}● saved${reset}`)
    })

  vmCmd
    .command("info")
    .description("Show VM system info (via neofetch)")
    .action(async () => {
      await vm.ensure()
      await vm.neofetch()
    })

  vmCmd
    .command("stop")
    .description("Stop the VM")
    .action(async () => {
      const spin = spinner("Stopping VM")
      try {
        await vm.stop()
        spin.succeed("VM stopped")
      } catch (err) {
        spin.fail(String((err as Error).message ?? err))
        process.exit(1)
      }
    })

  vmCmd
    .command("destroy")
    .description("Stop and delete the VM")
    .action(async () => {
      const spin = spinner("Destroying VM")
      try {
        await vm.destroy()
        spin.succeed("VM destroyed")
      } catch (err) {
        spin.fail(String((err as Error).message ?? err))
        process.exit(1)
      }
    })

  vmCmd
    .command("uncache")
    .description("Clear the package cache (next create will re-download)")
    .action(async () => {
      const had = await vm.clearCache()
      console.log(had ? "✔ Package cache cleared" : "No cache to clear")
    })
}