package main

// Backend defines the contract for invoking different AI CLI backends.
// Each backend is responsible for supplying the executable command and
// building the argument list based on the wrapper config.
type Backend interface {
	Name() string
	BuildArgs(cfg *Config, targetArg string) []string
	Command() string
}

type CodexBackend struct{}

func (CodexBackend) Name() string { return "codex" }
func (CodexBackend) Command() string {
	return "codex"
}
func (CodexBackend) BuildArgs(cfg *Config, targetArg string) []string {
	return buildCodexArgs(cfg, targetArg)
}

type ClaudeBackend struct{}

func (ClaudeBackend) Name() string { return "claude" }
func (ClaudeBackend) Command() string {
	return "claude"
}
func (ClaudeBackend) BuildArgs(cfg *Config, targetArg string) []string {
	if cfg == nil {
		return nil
	}
	args := []string{"-p"}

	// Default to skip permissions for Claude backend
	if !cfg.SkipPermissions {
		args = append(args, "--dangerously-skip-permissions")
	}

	workdir := cfg.WorkDir
	if workdir == "" {
		workdir = defaultWorkdir
	}

	if cfg.Mode == "resume" {
		if cfg.SessionID != "" {
			args = append(args, "--session-id", cfg.SessionID)
		}
	} else {
		args = append(args, "-C", workdir)
	}

	args = append(args, "--output-format", "stream-json", "--verbose", targetArg)

	return args
}

type GeminiBackend struct{}

func (GeminiBackend) Name() string { return "gemini" }
func (GeminiBackend) Command() string {
	return "gemini"
}
func (GeminiBackend) BuildArgs(cfg *Config, targetArg string) []string {
	if cfg == nil {
		return nil
	}
	args := []string{"-o", "stream-json", "-y"}

	workdir := cfg.WorkDir
	if workdir == "" {
		workdir = defaultWorkdir
	}

	if cfg.Mode == "resume" {
		if cfg.SessionID != "" {
			args = append(args, "--session-id", cfg.SessionID)
		}
	} else {
		args = append(args, "-C", workdir)
	}

	args = append(args, "-p", targetArg)

	return args
}