package run

import (
	"context"
	"fmt"

	"gitea.stevedudenhoeffer.com/steve/majordomo/llm"

	"gitea.stevedudenhoeffer.com/steve/executus/tool"
)

// addDelegationTools adds a delegation tool to the toolbox for each
// SkillPalette / SubAgentPalette entry, backed by the PaletteSource:
//
//   - skill__<name> invokes the named saved skill with structured inputs.
//   - agent__<name> invokes the named sub-agent with a prompt.
//
// Each delegated call runs as a CHILD of the current run (parentRunID =
// inv.RunID), inheriting the caller + channel. No-op when palette is nil or both
// palettes are empty — so an agent with no palette (or a host with no
// PaletteSource) simply has no delegation tools, exactly as before.
func addDelegationTools(box *llm.Toolbox, ra RunnableAgent, inv tool.Invocation, palette PaletteSource) error {
	if palette == nil {
		return nil
	}
	seen := map[string]bool{} // dedupe across both palettes by final tool name
	for _, name := range ra.SkillPalette {
		name := name // capture
		toolName := "skill__" + name
		if name == "" || seen[toolName] { // skip empty / duplicate palette entries
			continue
		}
		seen[toolName] = true
		t := llm.DefineTool(
			toolName,
			fmt.Sprintf("Delegate the task to the %q skill. Provide its declared inputs.", name),
			func(ctx context.Context, args skillDelegateArgs) (any, error) {
				out, _, status, err := palette.InvokeSkill(ctx, inv.CallerID, inv.ChannelID, name, args.Inputs, inv.RunID)
				if err != nil {
					return nil, delegationErr("skill", name, out, err)
				}
				return delegationResult(name, "skill", out, status), nil
			},
		)
		if err := box.Add(t); err != nil {
			return fmt.Errorf("add %s: %w", toolName, err)
		}
	}
	for _, name := range ra.SubAgentPalette {
		name := name // capture
		toolName := "agent__" + name
		if name == "" || seen[toolName] {
			continue
		}
		seen[toolName] = true
		t := llm.DefineTool(
			toolName,
			fmt.Sprintf("Delegate the task to the %q sub-agent with a natural-language prompt.", name),
			func(ctx context.Context, args agentDelegateArgs) (any, error) {
				out, _, status, err := palette.InvokeAgent(ctx, inv.CallerID, inv.ChannelID, name, args.Prompt, inv.RunID, "", "", nil, nil)
				if err != nil {
					return nil, delegationErr("agent", name, out, err)
				}
				return delegationResult(name, "agent", out, status), nil
			},
		)
		if err := box.Add(t); err != nil {
			return fmt.Errorf("add %s: %w", toolName, err)
		}
	}
	return nil
}

// delegationResult surfaces a non-ok child status to the parent agent (so it can
// react to a timeout/cancel/budget stop) while still passing the partial output.
func delegationResult(name, kind, out, status string) string {
	if status != "" && status != "ok" {
		header := fmt.Sprintf("[%s %q ended with status %q]", kind, name, status)
		if out == "" { // no trailing blank line when there's no body
			return header
		}
		return header + "\n" + out
	}
	return out
}

// delegationErr wraps a hard delegation failure, folding in any partial output
// the child produced before failing (so it isn't silently lost).
func delegationErr(kind, name, partial string, err error) error {
	if partial != "" {
		return fmt.Errorf("%s %q failed (partial output: %q): %w", kind, name, partial, err)
	}
	return fmt.Errorf("%s %q failed: %w", kind, name, err)
}

type skillDelegateArgs struct {
	Inputs map[string]any `json:"inputs" description:"Inputs for the skill, matching its declared input schema."`
}

type agentDelegateArgs struct {
	Prompt string `json:"prompt" description:"The task/prompt to hand the sub-agent."`
}