package view

import (
	"errors"
	"fmt"
	"io"
	"net/http"
	"strconv"
	"time"

	"github.com/AlecAivazis/survey/v2"
	"github.com/MakeNowJust/heredoc"
	"github.com/cli/cli/api"
	"github.com/cli/cli/internal/ghinstance"
	"github.com/cli/cli/internal/ghrepo"
	"github.com/cli/cli/pkg/cmd/run/download"
	"github.com/cli/cli/pkg/cmd/run/shared"
	"github.com/cli/cli/pkg/cmdutil"
	"github.com/cli/cli/pkg/iostreams"
	"github.com/cli/cli/pkg/prompt"
	"github.com/cli/cli/utils"
	"github.com/spf13/cobra"
)

type ViewOptions struct {
	HttpClient func() (*http.Client, error)
	IO         *iostreams.IOStreams
	BaseRepo   func() (ghrepo.Interface, error)

	RunID      string
	JobID      string
	Verbose    bool
	ExitStatus bool
	Log        bool

	Prompt bool

	Now func() time.Time
}

func NewCmdView(f *cmdutil.Factory, runF func(*ViewOptions) error) *cobra.Command {
	opts := &ViewOptions{
		IO:         f.IOStreams,
		HttpClient: f.HttpClient,
		Now:        time.Now,
	}
	cmd := &cobra.Command{
		Use:    "view [<run-id>]",
		Short:  "View a summary of a workflow run",
		Args:   cobra.MaximumNArgs(1),
		Hidden: true,
		Example: heredoc.Doc(`
		  # Interactively select a run to view, optionally drilling down to a job
		  $ gh run view

		  # View a specific run
		  $ gh run view 12345

			# View a specific job within a run
			$ gh run view --job 456789

			# View the full log for a specific job
			$ gh run view --log --job 456789

		  # Exit non-zero if a run failed
		  $ gh run view 0451 -e && echo "run pending or passed"
		`),
		// TODO should exit status respect only a selected job if --job is passed?
		RunE: func(cmd *cobra.Command, args []string) error {
			// support `-R, --repo` override
			opts.BaseRepo = f.BaseRepo

			if len(args) == 0 && opts.JobID == "" {
				if !opts.IO.CanPrompt() {
					return &cmdutil.FlagError{Err: errors.New("run or job ID required when not running interactively")}
				} else {
					opts.Prompt = true
				}
			} else if len(args) > 0 {
				opts.RunID = args[0]
			}

			if opts.RunID != "" && opts.JobID != "" {
				opts.RunID = ""
				if opts.IO.CanPrompt() {
					cs := opts.IO.ColorScheme()
					fmt.Fprintf(opts.IO.ErrOut, "%s both run and job IDs specified; ignoring run ID\n", cs.WarningIcon())
				}
			}

			if runF != nil {
				return runF(opts)
			}
			return runView(opts)
		},
	}
	cmd.Flags().BoolVarP(&opts.Verbose, "verbose", "v", false, "Show job steps")
	// TODO should we try and expose pending via another exit code?
	cmd.Flags().BoolVar(&opts.ExitStatus, "exit-status", false, "Exit with non-zero status if run failed")
	cmd.Flags().StringVarP(&opts.JobID, "job", "j", "", "View a specific job ID from a run")
	cmd.Flags().BoolVar(&opts.Log, "log", false, "View full log for either a run or specific job")

	return cmd
}

func runView(opts *ViewOptions) error {
	httpClient, err := opts.HttpClient()
	if err != nil {
		return fmt.Errorf("failed to create http client: %w", err)
	}
	client := api.NewClientFromHTTP(httpClient)

	repo, err := opts.BaseRepo()
	if err != nil {
		return fmt.Errorf("failed to determine base repo: %w", err)
	}

	jobID := opts.JobID
	runID := opts.RunID
	var selectedJob *shared.Job
	var run *shared.Run
	var jobs []shared.Job

	defer opts.IO.StopProgressIndicator()

	if jobID != "" {
		opts.IO.StartProgressIndicator()
		selectedJob, err = getJob(client, repo, jobID)
		opts.IO.StopProgressIndicator()
		if err != nil {
			return fmt.Errorf("failed to get job: %w", err)
		}
		// TODO once more stuff is merged, standardize on using ints
		runID = fmt.Sprintf("%d", selectedJob.RunID)
	}

	cs := opts.IO.ColorScheme()

	if opts.Prompt {
		// TODO arbitrary limit
		opts.IO.StartProgressIndicator()
		runs, err := shared.GetRuns(client, repo, 10)
		opts.IO.StopProgressIndicator()
		if err != nil {
			return fmt.Errorf("failed to get runs: %w", err)
		}
		runID, err = shared.PromptForRun(cs, runs)
		if err != nil {
			return err
		}
	}

	opts.IO.StartProgressIndicator()
	run, err = shared.GetRun(client, repo, runID)
	opts.IO.StopProgressIndicator()
	if err != nil {
		return fmt.Errorf("failed to get run: %w", err)
	}

	if opts.Prompt {
		opts.IO.StartProgressIndicator()
		jobs, err = shared.GetJobs(client, repo, *run)
		opts.IO.StopProgressIndicator()
		if err != nil {
			return err
		}
		if len(jobs) > 1 {
			selectedJob, err = promptForJob(cs, jobs)
			if err != nil {
				return err
			}
		}
	}

	opts.IO.StartProgressIndicator()

	if opts.Log && selectedJob != nil {
		r, err := jobLog(httpClient, repo, selectedJob.ID)
		if err != nil {
			return err
		}
		opts.IO.StopProgressIndicator()

		err = opts.IO.StartPager()
		if err != nil {
			return err
		}
		defer opts.IO.StopPager()

		if _, err := io.Copy(opts.IO.Out, r); err != nil {
			return fmt.Errorf("failed to read log: %w", err)
		}

		if opts.ExitStatus && shared.IsFailureState(run.Conclusion) {
			return cmdutil.SilentError
		}

		return nil
	}

	// TODO support --log without selectedJob

	if selectedJob == nil && len(jobs) == 0 {
		jobs, err = shared.GetJobs(client, repo, *run)
		opts.IO.StopProgressIndicator()
		if err != nil {
			return fmt.Errorf("failed to get jobs: %w", err)
		}
	} else if selectedJob != nil {
		jobs = []shared.Job{*selectedJob}
	}

	prNumber := ""
	number, err := shared.PullRequestForRun(client, repo, *run)
	if err == nil {
		prNumber = fmt.Sprintf(" #%d", number)
	}

	var artifacts []download.Artifact
	if selectedJob == nil {
		artifacts, err = download.ListArtifacts(httpClient, repo, strconv.Itoa(run.ID))
		if err != nil {
			return fmt.Errorf("failed to get artifacts: %w", err)
		}
	}

	var annotations []shared.Annotation

	var annotationErr error
	var as []shared.Annotation
	for _, job := range jobs {
		as, annotationErr = shared.GetAnnotations(client, repo, job)
		if annotationErr != nil {
			break
		}
		annotations = append(annotations, as...)
	}

	opts.IO.StopProgressIndicator()

	if annotationErr != nil {
		return fmt.Errorf("failed to get annotations: %w", annotationErr)
	}

	out := opts.IO.Out

	ago := opts.Now().Sub(run.CreatedAt)

	fmt.Fprintln(out)
	fmt.Fprintln(out, shared.RenderRunHeader(cs, *run, utils.FuzzyAgo(ago), prNumber))
	fmt.Fprintln(out)

	if len(jobs) == 0 && run.Conclusion == shared.Failure {
		fmt.Fprintf(out, "%s %s\n",
			cs.FailureIcon(),
			cs.Bold("This run likely failed because of a workflow file issue."))

		fmt.Fprintln(out)
		fmt.Fprintf(out, "For more information, see: %s\n", cs.Bold(run.URL))

		if opts.ExitStatus {
			return cmdutil.SilentError
		}
		return nil
	}

	if selectedJob == nil {
		fmt.Fprintln(out, cs.Bold("JOBS"))
		fmt.Fprintln(out, shared.RenderJobs(cs, jobs, opts.Verbose))
	} else {
		fmt.Fprintln(out, shared.RenderJobs(cs, jobs, true))
	}

	if len(annotations) > 0 {
		fmt.Fprintln(out)
		fmt.Fprintln(out, cs.Bold("ANNOTATIONS"))
		fmt.Fprintln(out, shared.RenderAnnotations(cs, annotations))
	}

	if selectedJob == nil {
		var validArtifacts []download.Artifact
		for _, a := range artifacts {
			if !a.Expired {
				validArtifacts = append(validArtifacts, a)
			}
		}
		if len(validArtifacts) > 0 {
			fmt.Fprintln(out)
			fmt.Fprintln(out, cs.Bold("ARTIFACTS"))
			for _, a := range validArtifacts {
				fmt.Fprintln(out, a.Name)
			}
		}

		fmt.Fprintln(out)
		fmt.Fprintln(out, "For more information about a job, try: gh run view --job=<job-id>")
		// TODO note about run view --log when that exists
		fmt.Fprintf(out, cs.Gray("view this run on GitHub: %s\n"), run.URL)
	} else {
		fmt.Fprintln(out)
		// TODO this does not exist yet
		fmt.Fprintf(out, "To see the full job log, try: gh run view --log --job=%d\n", selectedJob.ID)
		fmt.Fprintf(out, cs.Gray("view this run on GitHub: %s\n"), run.URL)
	}

	if opts.ExitStatus && shared.IsFailureState(run.Conclusion) {
		return cmdutil.SilentError
	}

	return nil
}

func getJob(client *api.Client, repo ghrepo.Interface, jobID string) (*shared.Job, error) {
	path := fmt.Sprintf("repos/%s/actions/jobs/%s", ghrepo.FullName(repo), jobID)

	var result shared.Job
	err := client.REST(repo.RepoHost(), "GET", path, nil, &result)
	if err != nil {
		return nil, err
	}

	return &result, nil
}

func jobLog(httpClient *http.Client, repo ghrepo.Interface, jobID int) (io.ReadCloser, error) {
	url := fmt.Sprintf("%srepos/%s/actions/jobs/%d/logs",
		ghinstance.RESTPrefix(repo.RepoHost()), ghrepo.FullName(repo), jobID)
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, err
	}

	resp, err := httpClient.Do(req)
	if err != nil {
		return nil, err
	}

	if resp.StatusCode == 404 {
		return nil, errors.New("job not found")
	} else if resp.StatusCode != 200 {
		return nil, api.HandleHTTPError(resp)
	}

	return resp.Body, nil
}

func promptForJob(cs *iostreams.ColorScheme, jobs []shared.Job) (*shared.Job, error) {
	candidates := []string{"View all jobs in this run"}
	for _, job := range jobs {
		symbol, _ := shared.Symbol(cs, job.Status, job.Conclusion)
		candidates = append(candidates, fmt.Sprintf("%s %s", symbol, job.Name))
	}

	var selected int
	err := prompt.SurveyAskOne(&survey.Select{
		Message:  "View a specific job in this run?",
		Options:  candidates,
		PageSize: 12,
	}, &selected)
	if err != nil {
		return nil, err
	}

	if selected > 0 {
		return &jobs[selected-1], nil
	}

	// User wants to see all jobs
	return nil, nil
}