package config

import (
	"os"
	"path/filepath"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

const validKey = "sha256:0000000000000000000000000000000000000000000000000000000000000000"

func setValid(t *testing.T) {
	t.Setenv("MASTER_URL", "wss://10.0.0.5:8090/agent")
	t.Setenv("MASTER_KEY", validKey)
	t.Setenv("AGENT_TOKEN", "pua_abc")
	t.Setenv("SELF_ID", "")
	t.Setenv("LOG_LEVEL", "")
	t.Setenv("UPDATE_TIMEOUT", "")
	t.Setenv("DOCKER_CONFIG", "")
}

func TestLoad_Valid(t *testing.T) {
	setValid(t)
	cfg, err := Load()
	require.NoError(t, err)
	host, _ := os.Hostname()
	assert.Equal(t, &Config{
		MasterURL: "wss://10.0.0.5:8090/agent", MasterKey: validKey, Token: "pua_abc",
		SelfID: host, LogLevel: "info", UpdateTimeout: 5 * time.Minute,
	}, cfg)
}

func TestLoad_Invalid(t *testing.T) {
	cases := []struct {
		name, key, value, wantErr string
	}{
		{"missing url", "MASTER_URL", "", "MASTER_URL is required"},
		{"plain ws", "MASTER_URL", "ws://10.0.0.5:8090/agent", "MASTER_URL must start with wss://"},
		{"missing key", "MASTER_KEY", "", "MASTER_KEY is required"},
		{"malformed key", "MASTER_KEY", "abc", "MASTER_KEY must look like sha256:<64 hex>"},
		{"missing token", "AGENT_TOKEN", "", "AGENT_TOKEN is required"},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			setValid(t)
			t.Setenv(c.key, c.value)
			_, err := Load()
			assert.ErrorContains(t, err, c.wantErr)
		})
	}
}

func TestLoad_JobSettings(t *testing.T) {
	withConfig := func(t *testing.T, body string) string {
		dir := t.TempDir()
		require.NoError(t, os.WriteFile(filepath.Join(dir, "config.json"), []byte(body), 0o600))
		return dir
	}
	cases := []struct {
		name      string
		timeout   string
		dockerCfg func(t *testing.T) string
		wantTime  time.Duration
		wantErr   string
	}{
		{name: "defaults", wantTime: 5 * time.Minute},
		{name: "custom timeout", timeout: "90s", wantTime: 90 * time.Second},
		{name: "zero timeout", timeout: "0", wantErr: "UPDATE_TIMEOUT"},
		{name: "garbage timeout", timeout: "abc", wantErr: "UPDATE_TIMEOUT"},
		{name: "docker config without file", dockerCfg: func(t *testing.T) string { return t.TempDir() }, wantErr: "DOCKER_CONFIG"},
		{name: "docker config not json", dockerCfg: func(t *testing.T) string { return withConfig(t, "nope") }, wantErr: "not valid JSON"},
		{name: "docker config ok", dockerCfg: func(t *testing.T) string { return withConfig(t, `{"auths":{}}`) }, wantTime: 5 * time.Minute},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			setValid(t)
			t.Setenv("UPDATE_TIMEOUT", c.timeout)
			dir := ""
			if c.dockerCfg != nil {
				dir = c.dockerCfg(t)
				t.Setenv("DOCKER_CONFIG", dir)
			}
			cfg, err := Load()
			if c.wantErr != "" {
				assert.ErrorContains(t, err, c.wantErr)
				return
			}
			require.NoError(t, err)
			assert.Equal(t, c.wantTime, cfg.UpdateTimeout)
			assert.Equal(t, dir, cfg.DockerConfig)
		})
	}
}