package cli

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"gitea.maximumdirect.net/eric/weatherreporter/internal/app"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/promptexec"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
)

func TestGenerateInputFailuresDoNotConstructOrExecute(t *testing.T) {
	configPath := actionConfigPath(t)
	for _, tt := range []struct {
		name    string
		args    []string
		wantErr string
	}{
		{name: "MissingReport", args: nil, wantErr: "generate requires a report name"},
		{name: "UnknownReport", args: []string{"unknown"}, wantErr: "unknown generate report"},
		{name: "MissingDailyDate", args: []string{"daily", "--config", filepath.Join(t.TempDir(), "missing.yml")}, wantErr: "generate daily requires --date YYYY-MM-DD"},
		{name: "MalformedDailyDate", args: []string{"daily", "--date", "not-a-date", "--config", configPath}},
		{name: "MalformedTodayDate", args: []string{"today", "--date", "not-a-date", "--config", configPath}},
		{name: "UnexpectedArgument", args: []string{"today", "extra"}},
		{name: "UnsupportedFlag", args: []string{"today", "--out-dir", "reports"}},
	} {
		t.Run(tt.name, func(t *testing.T) {
			factoryCalls, applicationCalls := 0, 0
			runner := Runner{
				Clock: timeutil.FixedClock{Time: time.Date(2026, 5, 29, 8, 30, 0, 0, time.UTC)},
				ExecutorFactory: func(PromptExecutorConfig) (promptexec.Executor, error) {
					factoryCalls++
					return &factoryExecutor{}, nil
				},
				generateDetailed: func(context.Context, app.GenerateRequest) (*app.ReportResult, error) {
					applicationCalls++
					return nil, nil
				},
			}
			var stdout, stderr bytes.Buffer
			err := runner.Run(context.Background(), append([]string{"generate"}, tt.args...), &stdout, &stderr)
			if err == nil {
				t.Fatal("Run() error = nil")
			}
			if tt.wantErr != "" && !strings.Contains(err.Error(), tt.wantErr) {
				t.Fatalf("Run() error = %q, want %q", err, tt.wantErr)
			}
			if factoryCalls != 0 || applicationCalls != 0 || stdout.Len() != 0 || stderr.Len() != 0 {
				t.Fatalf("factory/application calls/output = %d/%d/%q/%q", factoryCalls, applicationCalls, stdout.String(), stderr.String())
			}
		})
	}
}

func TestGenerateCommandProjectsActionResults(t *testing.T) {
	configPath := actionConfigPath(t)
	failure := errors.New("prompt execution failed")
	for _, tt := range []struct {
		name      string
		quiet     bool
		actionErr error
	}{
		{name: "Success"},
		{name: "Failure", actionErr: failure},
		{name: "QuietFailure", quiet: true, actionErr: failure},
	} {
		t.Run(tt.name, func(t *testing.T) {
			factoryCalls, applicationCalls := 0, 0
			executor := &factoryExecutor{}
			runner := Runner{
				Clock: timeutil.FixedClock{Time: time.Date(2026, 5, 29, 8, 30, 0, 0, time.UTC)},
				ExecutorFactory: func(PromptExecutorConfig) (promptexec.Executor, error) {
					factoryCalls++
					return executor, nil
				},
				generateDetailed: func(_ context.Context, req app.GenerateRequest) (*app.ReportResult, error) {
					applicationCalls++
					if req.Executor != executor {
						t.Fatal("generate request did not receive the constructed executor")
					}
					return generatedReportResult(), tt.actionErr
				},
			}
			args := []string{"generate", "daily", "--date", "2026-05-29", "--config", configPath}
			if tt.quiet {
				args = append(args, "--quiet")
			}
			var stdout, stderr bytes.Buffer
			err := runner.Run(context.Background(), args, &stdout, &stderr)
			if !errors.Is(err, tt.actionErr) || factoryCalls != 1 || applicationCalls != 1 || stderr.Len() != 0 {
				t.Fatalf("error/calls/stderr = %v/%d/%d/%q", err, factoryCalls, applicationCalls, stderr.String())
			}
			if tt.quiet {
				if stdout.Len() != 0 {
					t.Fatalf("quiet stdout = %q, want empty", stdout.String())
				}
				return
			}

			var summary generateSummary
			if err := json.Unmarshal(stdout.Bytes(), &summary); err != nil {
				t.Fatalf("decode summary: %v", err)
			}
			wantStatus, wantError := summaryStatusSucceeded, ""
			if tt.actionErr != nil {
				wantStatus, wantError = summaryStatusFailed, tt.actionErr.Error()
			}
			if summary.Command != commandGenerate || summary.Status != wantStatus || summary.Error != wantError || summary.OutputPath != "/reports/daily.md" {
				t.Fatalf("summary = %#v", summary)
			}
		})
	}
}

func actionConfigPath(t *testing.T) string {
	t.Helper()
	path := filepath.Join(t.TempDir(), "config.yml")
	if err := os.WriteFile(path, []byte("weather_api:\n  base_url: https://weather.api.example.com/\n"), 0o600); err != nil {
		t.Fatal(err)
	}
	return path
}

func generatedReportResult() *app.ReportResult {
	generatedAt := time.Date(2026, 5, 29, 13, 30, 0, 0, time.UTC)
	return &app.ReportResult{
		ReportID: report.Daily, ReportName: "Daily Report", PromptID: "weather.daily_generated_text", PromptVersion: "2.0.0",
		RunID: "daily-20260529", GeneratedAt: generatedAt, Timezone: "America/Chicago",
		ValidPeriod: timeutil.Period{Start: generatedAt, End: generatedAt.Add(24 * time.Hour)},
		ProfileID:   "weather-light", BackendID: "local", ModelName: "weather-model", ValidationStatus: promptexec.ValidationPassed,
		OutputPath: "/reports/daily.md",
	}
}