package agent

import "git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"

// defaultPurpose labels CallRecords when Options.Purpose is empty.
const defaultPurpose = "agent"

// buildRequest assembles a model.Request for one step: the agent's instructions
// prepended as a leading system message, plus the conversation messages, the
// configured model/temperature/max-tokens/purpose and the registered tool
// schemas. When a router is injected it overrides the model from the request
// contents, which is how vision requests are routed to the vision model.
func (a *Agent) buildRequest(messages []model.Message) model.Request {
	req := model.Request{
		Model:       a.opts.Model,
		Messages:    a.assembleMessages(messages),
		Temperature: a.temperature(),
		MaxTokens:   a.opts.MaxTokens,
		Purpose:     a.purpose(),
		Tools:       a.toolSchemas(),
	}
	if a.router != nil {
		if routeModel, _ := a.router.RouteRequest(req); routeModel != "" {
			req.Model = routeModel
		}
	}
	return req
}

// assembleMessages returns messages with the agent's instructions prepended as a
// leading system message when instructions are non-empty, otherwise the input
// slice is returned unchanged.
func (a *Agent) assembleMessages(messages []model.Message) []model.Message {
	if a.instructions == "" {
		return messages
	}
	out := make([]model.Message, 0, len(messages)+1)
	out = append(out, model.TextMessage(model.RoleSystem, a.instructions))
	out = append(out, messages...)
	return out
}

// temperature returns the temperature pointer to place in a Request. Zero maps
// to nil so the provider default applies.
func (a *Agent) temperature() *float64 {
	if a.opts.Temperature == 0 {
		return nil
	}
	t := a.opts.Temperature
	return &t
}

// purpose returns the CallRecord purpose label, defaulting to defaultPurpose.
func (a *Agent) purpose() string {
	if a.opts.Purpose == "" {
		return defaultPurpose
	}
	return a.opts.Purpose
}

// toolSchemas returns the registered tool schemas advertised to the model, or
// nil when no dispatcher is configured.
func (a *Agent) toolSchemas() []model.ToolSpec {
	if a.tools == nil {
		return nil
	}
	return a.tools.ToolSchemas()
}