package session

import (
	"ollie/agent"
	"os"
	"strings"
)

func LoadAgentConfig(agentsDir, name string, open func(string) (*os.File, error)) *agent.AgentConfig {
	if open == nil {
		open = os.Open
	}
	path := agent.AgentConfigPath(agentsDir, name)
	f, err := open(path)
	if err != nil {
		return nil
	}
	defer f.Close()
	cfg, _ := agent.Load(f)
	return cfg
}

// FormatEvent converts an agent Event to bytes for appending to a chat log.
// Streaming roles (assistant, reasoning) return only the content chunk;
// the caller (startEventLog) is responsible for writing the [[[role]]] header.
func FormatEvent(ev agent.Event) []byte {
	switch ev.Role {
	case "user":
		return []byte("[[[user]]]\n" + ev.Content + "\n[[[end]]]\n")
	case "assistant":
		return []byte(ev.Content)
	case "reasoning":
		return []byte(ev.Content)
	case "call":
		args := squashWhitespace(ev.Content)
		return []byte("[[[call:" + ev.Name + "]]]\n```\n" + args + "\n```\n[[[end]]]\n")
	case "tool":
		format := ev.OutputFormat
		fence := "```"
		if format != "" {
			fence += format
		}
		return []byte("[[[tool:" + ev.Name + "]]]\n" + fence + "\n" + strings.TrimRight(ev.Content, "\n") + "\n```\n[[[end]]]\n")
	case "error":
		return []byte("[[[error]]]\n" + ev.Content + "\n[[[end]]]\n")
	case "info":
		return []byte("[[[info]]]\n" + ev.Content + "\n[[[end]]]\n")
	case "retry":
		return []byte(ev.Content)
	case "stalled":
		return []byte("[[[stalled]]]\n[[[end]]]\n")
	case "maxsteps":
		return []byte("[[[maxsteps]]]\n" + ev.Content + "\n[[[end]]]\n")
	default:
		return nil
	}
}

func squashWhitespace(s string) string {
	return strings.Join(strings.Fields(s), " ")
}