// SPDX-License-Identifier: EUPL-1.2

package main

import (
	"bytes"
	"io"
	"os"
	"testing"

	agentpkg "dappco.re/go/agent"
	"dappco.re/go/agent/pkg/agentic"
	"dappco.re/go/core"
	"github.com/stretchr/testify/assert"
)

// newTestCore creates a minimal Core with application commands registered.
func newTestCore(t *testing.T) *core.Core {
	t.Helper()
	c := core.New(core.WithOption("name", "core-agent"))
	c.App().Version = "test"
	registerApplicationCommands(c)
	c.Cli().SetOutput(&bytes.Buffer{})
	return c
}

func withArgs(t *testing.T, args ...string) {
	t.Helper()
	previous := os.Args
	os.Args = append([]string(nil), args...)
	t.Cleanup(func() {
		os.Args = previous
	})
}

func captureStdout(t *testing.T, run func()) string {
	t.Helper()

	old := os.Stdout
	reader, writer, err := os.Pipe()
	if err != nil {
		t.Fatalf("pipe stdout: %v", err)
	}
	os.Stdout = writer
	defer func() {
		os.Stdout = old
	}()

	run()

	if err := writer.Close(); err != nil {
		t.Fatalf("close writer: %v", err)
	}
	data, err := io.ReadAll(reader)
	if err != nil {
		t.Fatalf("read stdout: %v", err)
	}
	if err := reader.Close(); err != nil {
		t.Fatalf("close reader: %v", err)
	}

	return string(data)
}

func TestCommands_ApplyLogLevel_Good(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	args := applyLogLevel([]string{"--quiet", "version"})
	assert.Equal(t, []string{"version"}, args)
}

func TestCommands_ApplyLogLevel_Bad(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	args := applyLogLevel([]string{"status"})
	assert.Equal(t, []string{"status"}, args)
}

func TestCommands_ApplyLogLevel_Ugly(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	args := applyLogLevel([]string{"version", "-q"})
	assert.Equal(t, []string{"version"}, args)
}

func TestCommands_StartupArgs_Good(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	withArgs(t, "core-agent", "--debug", "check")
	args := startupArgs()
	assert.Equal(t, []string{"check"}, args)
}

func TestCommands_StartupArgs_Bad(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	withArgs(t, "core-agent", "status")
	args := startupArgs()
	assert.Equal(t, []string{"status"}, args)
}

func TestCommands_StartupArgs_Ugly(t *testing.T) {
	defer core.SetLevel(core.LevelInfo)

	withArgs(t, "core-agent", "version", "-q")
	args := startupArgs()
	assert.Equal(t, []string{"version"}, args)
}

func TestCommands_RegisterApplicationCommands_Good(t *testing.T) {
	c := newTestCore(t)
	cmds := c.Commands()
	assert.Contains(t, cmds, "version")
	assert.Contains(t, cmds, "check")
	assert.Contains(t, cmds, "env")
	assert.Contains(t, cmds, "mcp")
	assert.Contains(t, cmds, "serve")
}

func TestCommands_Version_Good(t *testing.T) {
	c := newTestCore(t)
	agentpkg.Version = "0.8.0"
	t.Cleanup(func() {
		agentpkg.Version = ""
	})

	r := c.Cli().Run("version")
	assert.True(t, r.OK)
}

func TestCommands_VersionDev_Bad(t *testing.T) {
	c := newTestCore(t)
	agentpkg.Version = ""
	c.App().Version = "dev"

	r := c.Cli().Run("version")
	assert.True(t, r.OK)
}

func TestCommands_Check_Good(t *testing.T) {
	c := newTestCore(t)

	r := c.Cli().Run("check")
	assert.True(t, r.OK)
}

func TestCommands_Check_Good_BranchWorkspaceCount(t *testing.T) {
	c := newTestCore(t)

	ws := core.JoinPath(agentic.WorkspaceRoot(), "core", "go-io", "feature", "new-ui")
	assert.True(t, agentic.LocalFs().EnsureDir(agentic.WorkspaceRepoDir(ws)).OK)
	assert.True(t, agentic.LocalFs().EnsureDir(agentic.WorkspaceMetaDir(ws)).OK)
	assert.True(t, agentic.LocalFs().Write(core.JoinPath(ws, "status.json"), core.JSONMarshalString(agentic.WorkspaceStatus{
		Status: "running",
		Repo:   "go-io",
		Agent:  "codex",
	})).OK)

	output := captureStdout(t, func() {
		r := c.Cli().Run("check")
		assert.True(t, r.OK)
	})

	assert.Contains(t, output, "1 workspaces")
}

func TestCommands_Env_Good(t *testing.T) {
	c := newTestCore(t)

	r := c.Cli().Run("env")
	assert.True(t, r.OK)
}

func TestCommands_MCPService_Good(t *testing.T) {
	c := core.New(
		core.WithOption("name", "core-agent"),
		core.WithService(registerMCPService),
	)
	registerApplicationCommands(c)

	service, err := (applicationCommandSet{coreApp: c}).mcpService()
	assert.NoError(t, err)
	assert.NotNil(t, service)
}

func TestCommands_MCPService_Bad(t *testing.T) {
	_, err := (applicationCommandSet{coreApp: newTestCore(t)}).mcpService()
	assert.EqualError(t, err, "main.mcpService: mcp service not registered")
}

func TestCommands_MCPService_Ugly(t *testing.T) {
	c := core.New(core.WithOption("name", "core-agent"))
	assert.True(t, c.RegisterService("mcp", "invalid").OK)

	_, err := (applicationCommandSet{coreApp: c}).mcpService()
	assert.EqualError(t, err, "main.mcpService: mcp service has invalid type")
}

func TestCommands_ServeAddress_Good(t *testing.T) {
	c := newTestCore(t)

	addr := (applicationCommandSet{coreApp: c}).serveAddress(core.NewOptions(
		core.Option{Key: "addr", Value: "0.0.0.0:9201"},
	))

	assert.Equal(t, "0.0.0.0:9201", addr)
}

func TestCommands_ServeAddress_Bad(t *testing.T) {
	c := newTestCore(t)
	t.Setenv("CORE_AGENT_HTTP_ADDR", "")

	addr := (applicationCommandSet{coreApp: c}).serveAddress(core.NewOptions())

	assert.Equal(t, "127.0.0.1:9101", addr)
}

func TestCommands_ServeAddress_Ugly(t *testing.T) {
	c := newTestCore(t)

	addr := (applicationCommandSet{coreApp: c}).serveAddress(core.NewOptions(
		core.Option{Key: "_arg", Value: "127.0.0.1:9911"},
	))

	assert.Equal(t, "127.0.0.1:9911", addr)
}

func TestCommands_CliUnknown_Bad(t *testing.T) {
	c := newTestCore(t)
	r := c.Cli().Run("nonexistent")
	assert.False(t, r.OK)
}

func TestCommands_CliBanner_Good(t *testing.T) {
	c := newTestCore(t)
	c.Cli().SetBanner(func(_ *core.Cli) string {
		return "core-agent test"
	})
	r := c.Cli().Run()
	_ = r
}

func TestCommands_CliEmptyArgs_Ugly(t *testing.T) {
	c := newTestCore(t)
	r := c.Cli().Run()
	_ = r
}