package config

import (
	"github.com/johannSo/codey/internal/llm"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

// isolate points the config at a temp directory, so a test never reads or
// writes the developer's real ~/.config/codey.
func isolate(t *testing.T) string {
	t.Helper()
	dir := t.TempDir()
	t.Setenv("XDG_CONFIG_HOME", dir)
	return filepath.Join(dir, "codey", Filename)
}

// legacyPath is the pre-rename location, alongside the isolated new one.
func legacyPath(t *testing.T) string {
	t.Helper()
	dir := os.Getenv("XDG_CONFIG_HOME")
	if dir == "" {
		t.Fatal("legacyPath called outside isolate")
	}
	return filepath.Join(dir, legacyDir, Filename)
}

func writeConfig(t *testing.T, path, body string) {
	t.Helper()
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
		t.Fatal(err)
	}
}

// Someone who set Codey up before the rename should not be shown the
// wizard again: with no config at the new path, the old one still counts.
func TestLoadFallsBackToTheLegacyDirectory(t *testing.T) {
	isolate(t)
	writeConfig(t, legacyPath(t), `{"model":"claude-sonnet-5","setup":"done"}`)

	cfg, found, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if !found {
		t.Fatal("a config under the old name was not found")
	}
	if cfg.Model != "claude-sonnet-5" || !cfg.Done() {
		t.Errorf("the old config did not survive the fallback: %+v", cfg)
	}
}

// The fallback is a read, not a migration: the old file is left exactly where
// it was, so an older build still finds the settings it wrote.
func TestLoadLeavesTheLegacyFileAlone(t *testing.T) {
	path := isolate(t)
	old := legacyPath(t)
	writeConfig(t, old, `{"model":"claude-sonnet-5"}`)

	if _, _, err := Load(); err != nil {
		t.Fatalf("Load: %v", err)
	}
	if _, err := os.Stat(old); err != nil {
		t.Errorf("the old config was moved or removed by a read: %v", err)
	}
	if _, err := os.Stat(path); err == nil {
		t.Error("Load wrote to the new path; only Save may do that")
	}
}

// Once there is a config under the new name it wins outright, even if a stale
// one is still sitting in the old directory.
func TestNewConfigBeatsTheLegacyOne(t *testing.T) {
	path := isolate(t)
	writeConfig(t, path, `{"model":"claude-opus-5"}`)
	writeConfig(t, legacyPath(t), `{"model":"claude-sonnet-5"}`)

	cfg, found, err := Load()
	if err != nil || !found {
		t.Fatalf("Load: %v found=%v", err, found)
	}
	if cfg.Model != "claude-opus-5" {
		t.Errorf("the stale config won: %+v", cfg)
	}
}

// A corrupt file under the old name is still the user's settings, so it is
// reported rather than skipped over as if nothing were there.
func TestLegacyConfigThatCannotBeParsedIsReported(t *testing.T) {
	isolate(t)
	writeConfig(t, legacyPath(t), "{not json")

	_, found, err := Load()
	if err == nil {
		t.Fatal("a corrupt config under the old name was read as absent")
	}
	if found {
		t.Error("found=true alongside an error")
	}
}

func TestLoadReportsMissingWithoutError(t *testing.T) {
	isolate(t)

	cfg, found, err := Load()
	if err != nil {
		t.Fatalf("a missing config is the first-run signal, not an error: %v", err)
	}
	if found {
		t.Error("reported a config that does not exist")
	}
	if !cfg.Equal(Config{}) {
		t.Errorf("a missing config should come back zeroed, got %+v", cfg)
	}
}

func TestSaveThenLoadRoundTrips(t *testing.T) {
	path := isolate(t)

	want := Config{Model: "claude-sonnet-5", Effort: "high", Approvals: ApprovalsAcceptAll, Theme: "iris"}
	if err := Save(want); err != nil {
		t.Fatalf("Save: %v", err)
	}
	if _, err := os.Stat(path); err != nil {
		t.Fatalf("Save did not write %s: %v", path, err)
	}

	got, found, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if !found {
		t.Fatal("Load did not find the config Save just wrote")
	}
	want.Version = Version // stamped on write
	if !got.Equal(want) {
		t.Errorf("round trip changed the config:\n got %+v\nwant %+v", got, want)
	}
}

// A file we cannot parse must not be silently replaced: the user's settings
// are still in there, and the next Save would destroy them without the error
// ever being shown.
func TestLoadRejectsMalformedWithoutDiscardingIt(t *testing.T) {
	path := isolate(t)
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(path, []byte("{not json"), 0o644); err != nil {
		t.Fatal(err)
	}

	cfg, found, err := Load()
	if err == nil {
		t.Fatal("a malformed config loaded cleanly")
	}
	if found {
		t.Error("a malformed config was reported as usable")
	}
	if !cfg.Equal(Config{}) {
		t.Errorf("a malformed config produced values: %+v", cfg)
	}
	if b, _ := os.ReadFile(path); string(b) != "{not json" {
		t.Errorf("Load rewrote the file it could not parse: %q", b)
	}
	if !strings.Contains(err.Error(), path) {
		t.Errorf("the error does not say which file to fix: %v", err)
	}
}

func TestSaveCreatesTheDirectory(t *testing.T) {
	path := isolate(t)
	if err := Save(Config{Model: "claude-opus-5"}); err != nil {
		t.Fatalf("Save into a directory that does not exist yet: %v", err)
	}
	if _, err := os.Stat(path); err != nil {
		t.Fatal(err)
	}
}

// Unknown values are how a config written by a newer build, or edited by
// hand, reaches an older one. They are dropped rather than passed through to
// the API, which would fail the request with something unhelpful.
func TestLoadDropsValuesItDoesNotRecognise(t *testing.T) {
	path := isolate(t)
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		t.Fatal(err)
	}
	body := `{"version":1,"model":"claude-opus-5","effort":"extreme","approvals":"sometimes","theme":"neon"}`
	if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
		t.Fatal(err)
	}

	cfg, found, err := Load()
	if err != nil || !found {
		t.Fatalf("Load(found=%v): %v", found, err)
	}
	if cfg.Model != "claude-opus-5" {
		t.Errorf("a recognised field was dropped: %q", cfg.Model)
	}
	if cfg.Effort != "" || cfg.Approvals != "" || cfg.Theme != "" {
		t.Errorf("unrecognised values survived: %+v", cfg)
	}
}

// A level the API would reject must not survive a round trip, however it got
// into the file.
func TestLoadDropsAnEffortTheAPIWouldReject(t *testing.T) {
	for _, level := range llm.EffortLevels {
		if err := Save(Config{Effort: level}); err != nil {
			t.Fatal(err)
		}
		got, _, err := Load()
		if err != nil {
			t.Fatal(err)
		}
		if got.Effort != level {
			t.Errorf("%q did not survive a round trip: got %q", level, got.Effort)
		}
	}
}

// The config is only ever a default: a flag says what this run should do, and
// it has to win.
func TestFlagsOverrideTheConfig(t *testing.T) {
	cfg := Config{Model: "claude-sonnet-5", Effort: "low"}
	if got := Or("claude-opus-5", cfg.Model); got != "claude-opus-5" {
		t.Errorf("the flag lost to the config: %q", got)
	}
	if got := Or("", cfg.Model); got != "claude-sonnet-5" {
		t.Errorf("an unset flag did not fall through to the config: %q", got)
	}
	if got := Or("", ""); got != "" {
		t.Errorf("two empties produced %q", got)
	}
}

// The marker is what suppresses the wizard, so it has to survive the file
// unchanged — and a config without it has to keep reading as unfinished.
func TestSetupMarkerRoundTrips(t *testing.T) {
	isolate(t)

	if (Config{Model: "claude-opus-5"}).Done() {
		t.Error("a config with no marker reported the setup as done")
	}

	want := Config{Model: "claude-opus-5", Theme: "mono", Setup: SetupDone}
	if err := Save(want); err != nil {
		t.Fatal(err)
	}
	got, found, err := Load()
	if err != nil || !found {
		t.Fatalf("Load(found=%v): %v", found, err)
	}
	if !got.Done() {
		t.Errorf("the setup marker did not survive the round trip: %+v", got)
	}
}

// A config that exists but was never finished is the case the marker exists
// for: the file is there, and the wizard still has questions to ask.
func TestAnUnfinishedConfigIsNotDone(t *testing.T) {
	path := isolate(t)
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		t.Fatal(err)
	}
	// A marker of the wrong type — "setup": true, the obvious wrong guess for
	// someone editing by hand — is not in this list: that is a parse failure
	// for the whole file, which Load already reports rather than papering over.
	for _, body := range []string{
		`{"version":1,"theme":"mint"}`,
		`{"version":1,"theme":"mint","setup":"maybe"}`,
		`{"version":1,"theme":"mint","setup":""}`,
	} {
		if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
			t.Fatal(err)
		}
		cfg, _, _ := Load()
		if cfg.Done() {
			t.Errorf("%s reported the setup as done", body)
		}
		if cfg.Theme != "mint" {
			t.Errorf("%s lost the settings it did have: %+v", body, cfg)
		}
	}
}

func TestAutoCompactRoundTripsAndSanitizes(t *testing.T) {
	isolate(t)
	for _, v := range []string{AutoCompactOn, AutoCompactOff} {
		if err := Save(Config{AutoCompact: v}); err != nil {
			t.Fatal(err)
		}
		got, _, err := Load()
		if err != nil {
			t.Fatal(err)
		}
		if got.AutoCompact != v {
			t.Errorf("%q did not survive a round trip: got %q", v, got.AutoCompact)
		}
	}

	if err := Save(Config{AutoCompact: "sometimes"}); err != nil {
		t.Fatal(err)
	}
	got, _, err := Load()
	if err != nil {
		t.Fatal(err)
	}
	if got.AutoCompact != "" {
		t.Errorf("an unrecognised value survived: %q", got.AutoCompact)
	}
}

// Empty means "no preference", and no preference has to mean on: a config
// written before this setting existed must not silently stop the agent at 97%.
func TestAutoCompactDefaultsToOn(t *testing.T) {
	if !(Config{}).AutoCompactEnabled() {
		t.Error("an empty config should leave auto-compaction on")
	}
	if !(Config{AutoCompact: AutoCompactOn}).AutoCompactEnabled() {
		t.Error("an explicit on should be on")
	}
	if (Config{AutoCompact: AutoCompactOff}).AutoCompactEnabled() {
		t.Error("an explicit off should be off")
	}
}

// Every mode the wizard offers has to survive being written and read back,
// and a mode this build does not know has to fall back to none rather than to
// whatever sorts first — this is the one setting where guessing wrong sends
// the model's words to a third party.
func TestWebSearchRoundTripsAndSanitizes(t *testing.T) {
	isolate(t)
	for _, v := range WebSearchModes {
		if err := Save(Config{WebSearch: v}); err != nil {
			t.Fatal(err)
		}
		got, _, err := Load()
		if err != nil {
			t.Fatal(err)
		}
		if got.WebSearch != v {
			t.Errorf("%q did not survive a round trip: got %q", v, got.WebSearch)
		}
		if got.WebSearchMode() != v {
			t.Errorf("WebSearchMode() = %q, want %q", got.WebSearchMode(), v)
		}
	}

	if err := Save(Config{WebSearch: "google"}); err != nil {
		t.Fatal(err)
	}
	got, _, err := Load()
	if err != nil {
		t.Fatal(err)
	}
	if got.WebSearch != "" {
		t.Errorf("an unrecognised mode survived: %q", got.WebSearch)
	}
	if got.WebSearchMode() != WebSearchNone {
		t.Errorf("an unrecognised mode resolved to %q, want %q", got.WebSearchMode(), WebSearchNone)
	}
}

// A config written before web search existed must read as "no network", not
// as "whichever mode is first in the list".
func TestWebSearchDefaultsToNone(t *testing.T) {
	if got := (Config{}).WebSearchMode(); got != WebSearchNone {
		t.Errorf("an empty config means %q, want %q", got, WebSearchNone)
	}
}

// The search command is free text, so the only rules are that it survives and
// that "no preference" resolves to the shipped default rather than to an empty
// argv nobody can run.
func TestSearchCommandFallsBackToTheDefault(t *testing.T) {
	isolate(t)
	if got := (Config{}).SearchCommandLine(); got != DefaultSearchCommand {
		t.Errorf("empty resolved to %q, want the default %q", got, DefaultSearchCommand)
	}

	const custom = "mysearch --json {{query}}"
	if err := Save(Config{WebSearch: WebSearchCustom, SearchCommand: "  " + custom + "  "}); err != nil {
		t.Fatal(err)
	}
	got, _, err := Load()
	if err != nil {
		t.Fatal(err)
	}
	if got.SearchCommand != custom {
		t.Errorf("surrounding space was not trimmed: %q", got.SearchCommand)
	}
	if got.SearchCommandLine() != custom {
		t.Errorf("SearchCommandLine() = %q, want %q", got.SearchCommandLine(), custom)
	}
}

func TestHooksSurviveASaveAndLoad(t *testing.T) {
	isolate(t)

	want := Config{
		Model: "claude-sonnet-5",
		Hooks: map[string][]string{
			"blocked": {"notify-send codey \"$CODEY_MESSAGE\""},
			"run_end": {"true", "echo done"},
		},
	}
	if err := Save(want); err != nil {
		t.Fatalf("Save: %v", err)
	}

	got, _, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	want.Version = Version // stamped on write
	if !got.Equal(want) {
		t.Errorf("round trip changed the hooks:\n got %+v\nwant %+v", got.Hooks, want.Hooks)
	}
}

// The settings panel decides whether to rewrite the file by asking whether
// anything changed, and it must not lose a hook it never knew about.
func TestEqual(t *testing.T) {
	base := Config{Model: "m", Theme: "iris", Hooks: map[string][]string{"run_end": {"a"}}}

	cases := []struct {
		name  string
		a, b  Config
		equal bool
	}{
		{"the same config", base, base, true},
		{"a changed setting", base, Config{Model: "n", Theme: "iris", Hooks: base.Hooks}, false},
		{
			name:  "the same hooks in another map",
			a:     base,
			b:     Config{Model: "m", Theme: "iris", Hooks: map[string][]string{"run_end": {"a"}}},
			equal: true,
		},
		{
			name:  "a changed hook",
			a:     base,
			b:     Config{Model: "m", Theme: "iris", Hooks: map[string][]string{"run_end": {"b"}}},
			equal: false,
		},
		{
			name:  "a hook dropped",
			a:     base,
			b:     Config{Model: "m", Theme: "iris"},
			equal: false,
		},
		{
			name: "an event with no commands is no event at all",
			a:    Config{Model: "m"},
			b:    Config{Model: "m", Hooks: map[string][]string{"run_end": {}}},
			// A panel that rewrote the file over this would be saving nothing.
			equal: true,
		},
		{"two zero values", Config{}, Config{}, true},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			if got := c.a.Equal(c.b); got != c.equal {
				t.Errorf("Equal = %v, want %v", got, c.equal)
			}
			if got := c.b.Equal(c.a); got != c.equal {
				t.Errorf("Equal is not symmetric: reversed gave %v, want %v", got, c.equal)
			}
		})
	}
}

func TestMCPServersSurviveASaveAndLoad(t *testing.T) {
	isolate(t)

	want := Config{
		MCPServers: map[string]MCPServer{
			"docs": {Command: "npx", Args: []string{"-y", "@example/docs-mcp"}, Env: map[string]string{"DOCS_KEY": "k"}},
			"db":   {Command: "/usr/local/bin/db-mcp"},
		},
	}
	if err := Save(want); err != nil {
		t.Fatalf("Save: %v", err)
	}

	got, _, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	want.Version = Version
	if !got.Equal(want) {
		t.Errorf("round trip changed the servers:\n got %+v\nwant %+v", got.MCPServers, want.MCPServers)
	}
}

func TestEqualSeesMCPServers(t *testing.T) {
	base := Config{MCPServers: map[string]MCPServer{"db": {Command: "db-mcp", Args: []string{"--ro"}}}}
	cases := []struct {
		name  string
		b     Config
		equal bool
	}{
		{"the same server in another map", Config{MCPServers: map[string]MCPServer{"db": {Command: "db-mcp", Args: []string{"--ro"}}}}, true},
		{"a changed argument", Config{MCPServers: map[string]MCPServer{"db": {Command: "db-mcp", Args: []string{"--rw"}}}}, false},
		{"a changed environment", Config{MCPServers: map[string]MCPServer{"db": {Command: "db-mcp", Args: []string{"--ro"}, Env: map[string]string{"A": "1"}}}}, false},
		{"a server dropped", Config{}, false},
		{"a server renamed", Config{MCPServers: map[string]MCPServer{"sql": {Command: "db-mcp", Args: []string{"--ro"}}}}, false},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			if got := base.Equal(c.b); got != c.equal {
				t.Errorf("Equal = %v, want %v", got, c.equal)
			}
			if got := c.b.Equal(base); got != c.equal {
				t.Errorf("Equal is not symmetric: reversed gave %v, want %v", got, c.equal)
			}
		})
	}
	// Written to the file, a missing map and an empty one are the same
	// nothing, as are no args and an empty args list.
	if !(Config{}).Equal(Config{MCPServers: map[string]MCPServer{}}) {
		t.Error("an empty server map should equal a missing one")
	}
	if !(Config{MCPServers: map[string]MCPServer{"x": {Command: "x"}}}).Equal(Config{MCPServers: map[string]MCPServer{"x": {Command: "x", Args: []string{}}}}) {
		t.Error("no args should equal an empty args list")
	}
}