package main

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func saveBatchState(t *testing.T) {
	t.Helper()
	a, b, c, d, e, f, g := batchSourceType, batchInputs, batchTargetType, batchTargetDir, batchPackageName, batchKeepGoing, batchDryRun
	t.Cleanup(func() {
		batchSourceType, batchInputs, batchTargetType, batchTargetDir, batchPackageName, batchKeepGoing, batchDryRun = a, b, c, d, e, f, g
	})
}

func TestRunBatch_ConvertsEachInput(t *testing.T) {
	saveBatchState(t)
	dir := t.TempDir()
	writeTestJSON(t, filepath.Join(dir, "a.json"), []string{"users"})
	writeTestJSON(t, filepath.Join(dir, "b.json"), []string{"posts"})
	outDir := filepath.Join(dir, "out")

	batchSourceType, batchTargetType, batchTargetDir = "json", "yaml", outDir
	batchPackageName, batchKeepGoing, batchDryRun = "", false, false
	batchInputs = []string{filepath.Join(dir, "*.json")}

	cmd, _ := newDryRunCmd()
	if err := runBatch(cmd, nil); err != nil {
		t.Fatalf("batch: %v", err)
	}
	for _, name := range []string{"a.yaml", "b.yaml"} {
		if _, err := os.Stat(filepath.Join(outDir, name)); err != nil {
			t.Errorf("expected %s: %v", name, err)
		}
	}
}

func TestRunBatch_DryRunWritesNothing(t *testing.T) {
	saveBatchState(t)
	dir := t.TempDir()
	writeTestJSON(t, filepath.Join(dir, "a.json"), []string{"users"})
	outDir := filepath.Join(dir, "out")

	batchSourceType, batchTargetType, batchTargetDir = "json", "yaml", outDir
	batchPackageName, batchKeepGoing, batchDryRun = "", false, true
	batchInputs = []string{filepath.Join(dir, "a.json")}

	cmd, buf := newDryRunCmd()
	if err := runBatch(cmd, nil); err != nil {
		t.Fatalf("dry run: %v", err)
	}
	if _, err := os.Stat(outDir); !os.IsNotExist(err) {
		t.Fatal("dry run must not create the output directory")
	}
	if !strings.Contains(buf.String(), "users") || !strings.Contains(buf.String(), "a.yaml") {
		t.Errorf("plan incomplete:\n%s", buf.String())
	}
}

func TestRunBatch_FailureHandling(t *testing.T) {
	saveBatchState(t)
	dir := t.TempDir()
	writeTestJSON(t, filepath.Join(dir, "a.json"), []string{"users"})
	if err := os.WriteFile(filepath.Join(dir, "b.json"), []byte("{not json"), 0o644); err != nil {
		t.Fatal(err)
	}
	writeTestJSON(t, filepath.Join(dir, "c.json"), []string{"posts"})
	outDir := filepath.Join(dir, "out")

	batchSourceType, batchTargetType, batchTargetDir = "json", "yaml", outDir
	batchPackageName, batchDryRun = "", false
	batchInputs = []string{filepath.Join(dir, "*.json")}
	cmd, _ := newDryRunCmd()

	// Default: stop at first failure.
	batchKeepGoing = false
	err := runBatch(cmd, nil)
	if err == nil || !strings.Contains(err.Error(), "b.json") {
		t.Fatalf("expected failure naming b.json, got %v", err)
	}
	if _, statErr := os.Stat(filepath.Join(outDir, "c.yaml")); !os.IsNotExist(statErr) {
		t.Error("c.json should not be processed without --keep-going")
	}

	// --keep-going: remaining inputs are processed, exit still fails.
	batchKeepGoing = true
	if err := runBatch(cmd, nil); err == nil {
		t.Fatal("expected non-zero result with --keep-going")
	}
	if _, statErr := os.Stat(filepath.Join(outDir, "c.yaml")); statErr != nil {
		t.Errorf("c.yaml should be written with --keep-going: %v", statErr)
	}
}

func TestExpandBatchInputs(t *testing.T) {
	dir := t.TempDir()
	for _, n := range []string{"b.json", "a.json"} {
		if err := os.WriteFile(filepath.Join(dir, n), []byte("{}"), 0o644); err != nil {
			t.Fatal(err)
		}
	}
	got, err := expandBatchInputs([]string{filepath.Join(dir, "*.json"), filepath.Join(dir, "a.json")})
	if err != nil {
		t.Fatal(err)
	}
	if len(got) != 2 || filepath.Base(got[0]) != "a.json" || filepath.Base(got[1]) != "b.json" {
		t.Errorf("want sorted deduped [a b], got %v", got)
	}
	if _, err := expandBatchInputs([]string{filepath.Join(dir, "*.nope")}); err == nil {
		t.Error("unmatched pattern should error")
	}
}

func TestBatchOutputPaths(t *testing.T) {
	tests := []struct {
		name    string
		files   []string
		target  string
		want    []string
		wantErr string
	}{
		{"file target", []string{"x/a.dbml"}, "json", []string{"out/a.json"}, ""},
		{"dir target", []string{"x/a.json"}, "gorm", []string{"out/a"}, ""},
		{"collision", []string{"x/a.json", "y/a.json"}, "yaml", nil, "both write"},
		{"unsupported", []string{"a.json"}, "nope", nil, "unsupported target"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := batchOutputPaths(tt.files, tt.target, "out")
			if tt.wantErr != "" {
				if err == nil || !strings.Contains(err.Error(), tt.wantErr) {
					t.Fatalf("want error %q, got %v", tt.wantErr, err)
				}
				return
			}
			if err != nil || len(got) != len(tt.want) || got[0] != filepath.FromSlash(tt.want[0]) {
				t.Fatalf("got %v, %v; want %v", got, err, tt.want)
			}
		})
	}
}