/**
 * Shell picker for the `bash` tool on Windows.
 *
 * Historically the bash tool always fell back to `cmd.exe` on Windows — a
 * reasonable default for the small set of POSIX-style commands the tool was
 * built around (`echo`, `dir`, `cd`, `set`, etc.). That breaks when the
 * caller emits PowerShell-style commands (e.g. Codex on Windows routinely
 * emits `Get-Content`, `Get-ChildItem`, `Set-Location`, …), which `cmd.exe`
 * rejects with "'Get-Content' is not recognized as an internal or external
 * command, operable program or batch file." This module decides — purely from
 * the command string and a few well-known env vars — which shell should run
 * the command. It returns a tagged value; bash.ts does the actual spawn.
 *
 * The picker never spawns anything itself, so it is safe to unit-test in
 * isolation. Shell *resolution* (finding the actual binary on PATH) lives in
 * `_win32-resolve.ts` and runs at spawn time.
 * @see {@link ../../docs/configuration.md#windows-shell-selection-wrongstackshell} for user-facing documentation of the WRONGSTACK_SHELL env var and auto-detection behavior.
 *
 * Selection precedence (Windows only):
 *   1. `WRONGSTACK_SHELL` env var, if it names a known shell (cmd | powershell
 *      | pwsh). This is the override for users who want a fixed shell.
 *   2. Auto-detect: if the command "looks like" PowerShell — i.e. uses cmdlet
 *      verb-noun syntax, $-variables, subexpressions, here-strings, etc. —
 *      route to PowerShell. Prefers `pwsh` (PowerShell 7+) and falls back to
 *      `powershell` (Windows PowerShell 5.1) at spawn time.
 *   3. Default: `cmd.exe` (preserves legacy behavior).
 *
 * On non-Windows the picker is a no-op — bash.ts already routes through
 * `/bin/bash -c`. We return `'cmd'` as a sentinel value that means "the
 * platform default"; bash.ts maps it to the right binary.
 *
 * See docs/configuration.md § "Windows shell selection (WRONGSTACK_SHELL)" for
 * user-facing documentation of the env var and auto-detection behaviour.
 */
export type BashShell = 'cmd' | 'powershell' | 'pwsh';
/** Sentinel returned on POSIX — bash.ts maps this to `/bin/bash -c`. */
export declare const POSIX_DEFAULT: BashShell;
interface PickShellEnv {
    /** Read-only env view. Tests pass `{ get: (k) => process.env[k] }`. */
    get(key: string): string | undefined;
}
/**
 * Decide which shell should execute `command` on `platform`. Pure function —
 * no I/O, no side effects, no exceptions (invalid input returns the default).
 */
export declare function pickShell(platform: NodeJS.Platform, command: string, env: PickShellEnv): BashShell;
/**
 * Heuristic PowerShell detector. Conservative on purpose — false positives
 * route `cmd.exe` work into PowerShell (different parsing rules, different
 * exit-code semantics, sometimes very different stdout), which is more
 * disruptive than a single "command not recognized" error. We only return
 * true for patterns that are unambiguously PowerShell.
 *
 * Detected patterns:
 *   - cmdlet verb-noun syntax (`Get-`, `Set-`, `New-`, `Remove-`, `Add-`,
 *     `Clear-`, `Copy-`, `Move-`, `Rename-`, `Test-`, `Update-`, `Write-`,
 *     `Read-`, `Push-`, `Pop-`, `Invoke-`, `Start-`, `Stop-`, `Wait-`,
 *     `Out-`, `Format-`, `Group-`, `Measure-`, `Compare-`, `Resolve-`,
 *     `ConvertTo-`, `ConvertFrom-`, `Import-`, `Export-`, `Select-`,
 *     `Where-`, `ForEach-`, `Sort-`, `Tee-`, `Split-`, `Join-`, `Limit-`,
 *     `Skip-`, `Step-`, `Trace-`, `Debug-`, `Register-`, `Unregister-`,
 *     `Enable-`, `Disable-`, `Restart-`, `Suspend-`, `Resume-`, `Save-`,
 *     `Open-`, `Close-`, `Lock-`, `Unlock-`, `Mount-`, `Dismount-`,
 *     `Enter-`, `Exit-`, `Use-`, `Show-`, `Hide-`, `Find-`, `Search-`,
 *     `Watch-`, `Initialize-`, `Optimize-`, `Compress-`, `Expand-`,
 *     `Convert-`, `Merge-`, `Checkpoint-`, `Undo-`, `Redo-`, `Approve-`,
 *     `Deny-`, `Block-`, `Grant-`, `Revoke-`, `Assert-`, `Confirm-`,
 *     `Resolve-`, `Wait-`, `Receive-`, `Send-`, `Connect-`, `Disconnect-`,
 *     `Read-`, `Write-`).
 *   - $-prefixed variables (`$env:`, `$foo`, `$script:bar`, `$_`).
 *   - Subexpressions (`$(...)`).
 *   - Here-strings (`@"…"@`, `@'…'@`).
 *   - Splatting (`@(...)` at start of argument, `@{}` hash table).
 *   - PowerShell-comparison operators (`-eq`, `-ne`, `-lt`, `-gt`, `-le`,
 *     `-ge`, `-like`, `-notlike`, `-match`, `-notmatch`, `-contains`,
 *     `-in`, `-and`, `-or`, `-not`, `-band`, `-bor`, `-bxor`,
 *     `-replace`, `-split`, `-join`, `-is`, `-as`, `-f`).
 *   - `.ps1` extension mentioned in the command.
 *   - `&` call operator followed by a `$`-variable (`& $cmd ...`).
 *   - PowerShell-only aliases: `gci`, `gi`, `gp`, `gcm`, `gps`. Unix-style
 *     names (`ls`, `cat`, `cp`, `mv`, `rm`, `sl`) are deliberately NOT
 *     treated as PowerShell tells — they are Git-Bash/MSYS-normal on
 *     Windows and their PS alias semantics differ (`rm -rf` fails in PS).
 *   - `#requires` directive at start of script.
 *   - `param()` block at start of script.
 *
 *    The Windows-style path `C:\` alone is not a PowerShell tell — both
 *    shells accept it. We only flip on PS-specific syntax.
 *
 * The function is case-insensitive and tolerates leading whitespace.
 */
export declare function looksLikePowerShell(command: string): boolean;
/**
 * Extended PowerShell detection — patterns that are unambiguous but less
 * common than the verb-noun cmdlets caught by the first pass.
 *
 * Covers: -WhatIf / -Confirm / -ErrorAction flags, trailing `2>&1` in
 * combination with other PS signals, `[type]` casts, Where/ForEach/
 * Select-Object pipeline, PS comment blocks, Write-* output cmdlets,
 * registry paths (HKLM:/HKCU:), -AsPlainText, -PipelineVariable.
 */
export declare function looksLikePowerShellExtended(command: string): boolean;
/**
 * Wrap a user command for execution via `pwsh -Command -` (stdin pipe).
 *
 * The wrapper addresses four reliability gaps in Windows PowerShell:
 *
 * 1. **Console output encoding**: PS 5.1 outputs in the system codepage
 *    (often Windows-1252) which mojibakes non-ASCII. Setting
 *    `[Console]::OutputEncoding = [System.Text.Encoding]::UTF8` at the
 *    top of the script ensures UTF-8 output in both editions.
 *
 * 2. **Exit-code propagation**: Native commands (dotnet, npm, node, etc.)
 *    set `$LASTEXITCODE`. Without explicit propagation, `pwsh -Command -`
 *    exits 0 even when the native command failed. Running the command body
 *    and then exiting with `$LASTEXITCODE` when it is numeric preserves native
 *    exit codes without swallowing PowerShell output.
 *
 * 3. **Confirmation suppression**: `$ConfirmPreference='None'` suppresses
 *    interactive confirmation prompts (e.g. `-Confirm` cmdlets) so scripts
 *    don't block waiting for user input. `$WhatIfPreference=$false` ensures
 *    commands actually RUN (not just print what they would do).
 *
 * The caller encodes this script as UTF-16LE Base64 for `-EncodedCommand`.
 * Do not prefix it with a BOM: the encoded command is already decoded using
 * PowerShell's required UTF-16LE representation.
 */
export declare function wrapPowerShellScript(command: string): string;
/**
 * Return the argv prefix for a given shell. The bash tool passes a single
 * command string and expects the shell to interpret it. cmd.exe uses
 * `/c <cmd>`; PowerShell uses `-EncodedCommand <base64>`. The encoded payload
 * avoids quoting bugs for multi-line, quoted, and dollar-sign-laden scripts.
 */
export declare function shellArgs(shell: BashShell): string[];
/**
 * Post-failure diagnosis: when a Windows shell command exits non-zero, scan it
 * for bash/POSIX idioms the shell does not accept and return a short, targeted
 * hint (with the right replacement) so the model self-corrects on the next turn.
 *
 * Deliberately **failure-coupled** — the bash tool only calls this on a
 * non-zero exit. That keeps it noise-free (PowerShell aliases `ls`/`cat`/`rm`
 * succeed, so they never reach here) and side-steps shell-version nuance: `&&`
 * works in PowerShell 7 and cmd.exe (so those commands succeed and are never
 * flagged) but breaks in Windows PowerShell 5.1 (where the command fails and is
 * flagged). Never mutates or blocks — advisory only.
 *
 * Returns `undefined` when nothing actionable is found (including any POSIX
 * call — bash idioms are correct there).
 */
export declare function diagnoseBashism(command: string, shell: BashShell): string | undefined;
export {};
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