package main

import (
	"encoding/xml"
	"io"
	"path/filepath"
	"runtime"
	"strings"
	"testing"

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

// assertWellFormedXML fails if s is not parseable XML — a stronger
// guarantee than substring checks that the env injection didn't corrupt
// the plist into something launchctl can't load.
func assertWellFormedXML(t *testing.T, s string) {
	t.Helper()
	dec := xml.NewDecoder(strings.NewReader(s))
	for {
		_, err := dec.Token()
		if err == io.EOF {
			break
		}
		require.NoError(t, err, "plist must be well-formed XML")
	}
}

// TestRenderLaunchdPlist_NoXDG proves the launchd plist is valid and
// carries the substitutions it must — binary path, log path, label —
// and that with no XDG override captured it has no extra env entries
// (the pre-fix baseline behaviour, unchanged for the common case).
func TestRenderLaunchdPlist_NoXDG(t *testing.T) {
	out, err := renderLaunchdPlist(
		"com.zzet.gortex",
		"/usr/local/bin/gortex",
		"/Users/testuser/.gortex/cache/daemon.log",
		nil,
	)
	require.NoError(t, err)

	assert.Contains(t, out, "<key>Label</key>\n    <string>com.zzet.gortex</string>")
	assert.Contains(t, out, "<string>/usr/local/bin/gortex</string>")
	assert.Contains(t, out, "<string>daemon</string>")
	assert.Contains(t, out, "<string>start</string>")
	assert.Contains(t, out, "<key>RunAtLoad</key>")
	assert.Contains(t, out, "<key>KeepAlive</key>")
	assert.Contains(t, out, "/Users/testuser/.gortex/cache/daemon.log")
	// Homebrew paths must be on PATH so launchd can find a Homebrew-
	// installed gortex binary even when the LaunchAgent env is minimal.
	assert.Contains(t, out, "/opt/homebrew/bin")
	assert.NotContains(t, out, "XDG_", "no env entries when none captured")
	assertWellFormedXML(t, out)
}

// TestRenderLaunchdPlist_PropagatesXDG is the regression test for the
// service-ignores-XDG bug: when an XDG override is in effect at install
// time it must be baked into the plist so the supervised daemon resolves
// the same paths as the installing shell instead of falling back to
// ~/.gortex.
func TestRenderLaunchdPlist_PropagatesXDG(t *testing.T) {
	env := []serviceEnvVar{
		{Key: "XDG_CONFIG_HOME", Value: "/Users/testuser/.config"},
		{Key: "XDG_DATA_HOME", Value: "/Users/testuser/.local/share"},
	}
	out, err := renderLaunchdPlist(
		"com.zzet.gortex",
		"/usr/local/bin/gortex",
		"/Users/testuser/.config/gortex/daemon.log",
		env,
	)
	require.NoError(t, err)

	assert.Contains(t, out, "<key>XDG_CONFIG_HOME</key>\n        <string>/Users/testuser/.config</string>")
	assert.Contains(t, out, "<key>XDG_DATA_HOME</key>\n        <string>/Users/testuser/.local/share</string>")
	// PATH must still be present alongside the captured XDG vars.
	assert.Contains(t, out, "<key>PATH</key>")
	assertWellFormedXML(t, out)
}

// TestRenderLaunchdPlist_EscapesXML guards against a home path with an
// XML metacharacter producing a malformed, unloadable plist.
func TestRenderLaunchdPlist_EscapesXML(t *testing.T) {
	env := []serviceEnvVar{{Key: "XDG_CONFIG_HOME", Value: "/Users/a&b/.config"}}
	out, err := renderLaunchdPlist("com.zzet.gortex", "/opt/a&b/gortex", "/log&path", env)
	require.NoError(t, err)

	assert.Contains(t, out, "/Users/a&amp;b/.config")
	assert.Contains(t, out, "/opt/a&amp;b/gortex")
	assert.NotContains(t, out, "a&b", "raw ampersand must be escaped")
	assertWellFormedXML(t, out)
}

// TestRenderSystemdUnit_NoXDG confirms the Type=simple + Restart=on-failure
// contract and that no Environment= line is emitted when nothing was
// captured.
func TestRenderSystemdUnit_NoXDG(t *testing.T) {
	out, err := renderSystemdUnit(
		"/home/u/.local/bin/gortex",
		"/home/u/.gortex/cache/daemon.log",
		nil,
	)
	require.NoError(t, err)

	assert.Contains(t, out, "ExecStart=/home/u/.local/bin/gortex daemon start")
	assert.Contains(t, out, "Type=simple")
	assert.Contains(t, out, "Restart=on-failure")
	assert.Contains(t, out, "StandardOutput=append:/home/u/.gortex/cache/daemon.log")
	assert.Contains(t, out, "WantedBy=default.target")
	assert.NotContains(t, out, "Environment=", "no env line when none captured")
}

// TestRenderSystemdUnit_PropagatesXDG is the Linux analog of the launchd
// regression test, and also covers systemd quoting for a value with a
// space.
func TestRenderSystemdUnit_PropagatesXDG(t *testing.T) {
	env := []serviceEnvVar{
		{Key: "XDG_CACHE_HOME", Value: "/home/u/.cache"},
		{Key: "XDG_DATA_HOME", Value: "/home/u/has space"},
	}
	out, err := renderSystemdUnit(
		"/home/u/.local/bin/gortex",
		"/home/u/.cache/gortex/daemon.log",
		env,
	)
	require.NoError(t, err)

	assert.Contains(t, out, "Environment=XDG_CACHE_HOME=/home/u/.cache")
	// A value containing whitespace is double-quoted per systemd rules.
	assert.Contains(t, out, `Environment=XDG_DATA_HOME="/home/u/has space"`)

	// Environment lines must sit inside [Service], ahead of [Install].
	svcStart := strings.Index(out, "[Service]")
	installStart := strings.Index(out, "[Install]")
	require.Greater(t, svcStart, -1)
	require.Greater(t, installStart, svcStart)
	svc := out[svcStart:installStart]
	assert.Contains(t, svc, "Environment=XDG_CACHE_HOME=")
}

// TestXDGServiceEnv_OnlyAbsoluteSet pins the capture contract: only XDG
// vars that are set to an absolute path are propagated. Unset and
// relative values are ignored (the latter per the XDG spec, matching
// platform.unifiedDir).
func TestXDGServiceEnv_OnlyAbsoluteSet(t *testing.T) {
	t.Setenv("XDG_CONFIG_HOME", "/abs/config")
	t.Setenv("XDG_DATA_HOME", "relative/data") // ignored — not absolute
	t.Setenv("XDG_CACHE_HOME", "")              // ignored — empty/unset

	got := map[string]string{}
	for _, e := range xdgServiceEnv() {
		got[e.Key] = e.Value
	}

	assert.Equal(t, "/abs/config", got["XDG_CONFIG_HOME"])
	_, hasData := got["XDG_DATA_HOME"]
	assert.False(t, hasData, "relative XDG_DATA_HOME must be ignored")
	_, hasCache := got["XDG_CACHE_HOME"]
	assert.False(t, hasCache, "empty XDG_CACHE_HOME must be ignored")
}

func TestSystemdEnvValue_QuotesWhitespace(t *testing.T) {
	assert.Equal(t, "/home/u/.config", systemdEnvValue("/home/u/.config"))
	assert.Equal(t, `"/home/u/my data"`, systemdEnvValue("/home/u/my data"))
}

// TestSystemdEnvValue_EscapesPercent guards the systemd specifier escape:
// a literal % in a path must become %% or systemd expands it (e.g. %d)
// and the daemon resolves a different directory than was captured.
func TestSystemdEnvValue_EscapesPercent(t *testing.T) {
	assert.Equal(t, "/home/u/100%%dir", systemdEnvValue("/home/u/100%dir"))
	// percent + whitespace: escaped and quoted.
	assert.Equal(t, `"/home/u/a %%b c"`, systemdEnvValue("/home/u/a %b c"))
}

func TestLaunchdPlistPath_ResolvesUnderHome(t *testing.T) {
	if runtime.GOOS != "darwin" {
		t.Skip("launchd paths only meaningful on darwin")
	}
	path, err := launchdPlistPath()
	require.NoError(t, err)
	assert.Equal(t, "com.zzet.gortex.plist", filepath.Base(path))
	assert.Contains(t, path, filepath.Join("Library", "LaunchAgents"))
}

func TestSystemdUnitPath_ResolvesUnderHome(t *testing.T) {
	if runtime.GOOS != "linux" {
		t.Skip("systemd paths only meaningful on linux")
	}
	path, err := systemdUnitPath()
	require.NoError(t, err)
	assert.Equal(t, "com.zzet.gortex.service", filepath.Base(path))
	assert.Contains(t, path, filepath.Join(".config", "systemd", "user"))
}

// TestServiceCommands_RejectUnsupportedOS keeps the guard
// runDaemonInstallService uses from silently succeeding on Windows or
// other platforms we haven't wired.
func TestServiceCommands_RejectUnsupportedOS(t *testing.T) {
	if runtime.GOOS == "darwin" || runtime.GOOS == "linux" {
		t.Skip("this test only runs on unsupported platforms")
	}
	err := runDaemonInstallService(daemonInstallServiceCmd, nil)
	require.Error(t, err)
	assert.True(t, strings.Contains(err.Error(), "not supported"),
		"install must refuse on unsupported OS: %v", err)
}