import { describe, expect } from "bun:test"

import { LayerNode } from "@opencode-ai/core/effect/layer-node"

import { Effect, Layer } from "effect"

import type { Agent } from "../../src/agent/agent"

import { NamedError } from "@opencode-ai/core/util/error"

import { Skill } from "../../src/skill"

import { Permission } from "../../src/permission"

import { SystemPrompt } from "../../src/session/system"

import { MCP } from "../../src/mcp"

import { testEffect } from "../lib/effect"

const skills: Skill.Info[] = [

{

name: "zeta-skill",

description: "Zeta skill.",

location: "/tmp/zeta-skill/SKILL.md",

content: "# zeta-skill",

},

{

name: "alpha-skill",

description: "Alpha skill.",

location: "/tmp/alpha-skill/SKILL.md",

content: "# alpha-skill",

},

{

name: "middle-skill",

description: "Middle skill.",

location: "/tmp/middle-skill/SKILL.md",

content: "# middle-skill",

},

{

name: "manual-skill",

location: "/tmp/manual-skill/SKILL.md",

content: "# manual-skill",

},

]

const build: Agent.Info = {

name: "build",

mode: "primary",

permission: Permission.fromConfig({ "*": "allow" }),

options: {},

}

const it = testEffect(

LayerNode.compile(SystemPrompt.node, [

[

MCP.node,

Layer.mock(MCP.Service, {

instructions: () =>

Effect.succeed([

{

name: "guide-server",

instructions: "Use lookup before mutate.",

tools: [],

},

{

name: "tool-server",

instructions: "Prefer search before update.",

tools: ["tool-server_search", "tool-server_update"],

},

]),

}),

],

[

Skill.node,

Layer.succeed(

Skill.Service,

Skill.Service.of({

get: (name) => Effect.succeed(skills.find((skill) => skill.name === name)),

require: (name) => {

const info = skills.find((skill) => skill.name === name)

if (info) return Effect.succeed(info)

return Effect.fail(new Skill.NotFoundError({ name, available: skills.map((skill) => skill.name) }))

},

all: () => Effect.succeed(skills),

dirs: () => Effect.succeed([]),

available: () => Effect.succeed(skills),

}),

),

],

]),

)

describe("session.system", () => {

it.effect("skills output is sorted by name and stable across calls", () =>

Effect.gen(function* () {

const prompt = yield* SystemPrompt.Service

const first = yield* prompt.skills(build)

const second = yield* prompt.skills(build)

const output = first ?? (yield* Effect.fail(new NamedError.Unknown({ message: "missing skills output" })))

expect(first).toBe(second)

const alpha = output.indexOf("<name>alpha-skill</name>")

const middle = output.indexOf("<name>middle-skill</name>")

const zeta = output.indexOf("<name>zeta-skill</name>")

expect(alpha).toBeGreaterThan(-1)

expect(middle).toBeGreaterThan(alpha)

expect(zeta).toBeGreaterThan(middle)

expect(output).not.toContain("manual-skill")

}),

)

it.effect("MCP output includes connected server instructions", () =>

Effect.gen(function* () {

const prompt = yield* SystemPrompt.Service

const output = yield* prompt.mcp(build)

expect(output).toBe(

[

"<mcp_instructions>",

' <server name="guide-server">',

" Use lookup before mutate.",

" </server>",

' <server name="tool-server">',

" Prefer search before update.",

" </server>",

"</mcp_instructions>",

].join("\n"),

)

}),

)

it.effect("MCP output omits servers when all advertised tools are denied", () =>

Effect.gen(function* () {

const prompt = yield* SystemPrompt.Service

const output = yield* prompt.mcp(build, Permission.fromConfig({ "tool-server_*": "deny" }))

expect(output).toBe(

[

"<mcp_instructions>",

' <server name="guide-server">',

" Use lookup before mutate.",

" </server>",

"</mcp_instructions>",

].join("\n"),

)

}),

)

})