package api

import (
	"net/http"

	"git.golem15.com/golem15/summercms/modules/bouncer"
)

// The MCP view of the material answers (D-17, D-21): a material's body may
// hold transcript text, so an answer to an MCP tool call leaves it out
// unless the call asks for it with include_body, and a write answer never
// echoes it. Plain HTTP answers are unchanged.

// viaMCP reports whether r is an MCP tool call: a request pier dispatched
// in-process with the api_token marker. The marker lives on the context
// only, so an HTTP request can never carry it.
func viaMCP(r *http.Request) bool {
	_, ok := bouncer.Dispatched(r.Context(), "api_token")
	return ok
}

// includeBody reports whether r asks for the material body
// (include_body=true or 1).
func includeBody(r *http.Request) bool {
	return flag(r, "include_body")
}

// bodyOmitted reports whether leaving body out hides content.
func bodyOmitted(body *string) bool {
	return body != nil && *body != ""
}

// mcpMaterialDetailJSON is a published material under MCP without its body:
// the list fields and the files, with body_omitted when a non-empty body was
// left out. Body shadows the embedded one and stays nil.
type mcpMaterialDetailJSON struct {
	materialDetailJSON
	Body        *string `json:"body,omitempty"`
	BodyOmitted bool    `json:"body_omitted,omitempty"`
}

// mcpManagedMaterialJSON is a managed material under MCP without its body.
type mcpManagedMaterialJSON struct {
	managedMaterialJSON
	Body        *string `json:"body,omitempty"`
	BodyOmitted bool    `json:"body_omitted,omitempty"`
}

// mcpManagedMaterialDetailJSON is a managed material with its files under
// MCP without its body.
type mcpManagedMaterialDetailJSON struct {
	mcpManagedMaterialJSON
	Files []fileJSON `json:"files"`
}

// materialView is the answer of GET /materials/{id} (student): unchanged
// over plain HTTP; under MCP (mcp) without the body unless withBody.
func materialView(d materialDetailJSON, mcp, withBody bool) any {
	if !mcp || withBody {
		return d
	}
	return mcpMaterialDetailJSON{materialDetailJSON: d, BodyOmitted: bodyOmitted(d.Body)}
}

// managedMaterialView is a managed material: unchanged over plain HTTP;
// under MCP (mcp) without the body unless withBody (a write answer passes
// false, so it never echoes the body).
func managedMaterialView(m managedMaterialJSON, mcp, withBody bool) any {
	if !mcp || withBody {
		return m
	}
	return mcpManagedMaterialJSON{managedMaterialJSON: m, BodyOmitted: bodyOmitted(m.Body)}
}

// managedMaterialDetailView is a managed material with its files, under the
// same rule as managedMaterialView.
func managedMaterialDetailView(d managedMaterialDetailJSON, mcp, withBody bool) any {
	if !mcp || withBody {
		return d
	}
	return mcpManagedMaterialDetailJSON{
		mcpManagedMaterialJSON: mcpManagedMaterialJSON{managedMaterialJSON: d.managedMaterialJSON, BodyOmitted: bodyOmitted(d.Body)},
		Files:                  d.Files,
	}
}