// Package gtr defines a standard test report format and provides convenience
// methods to create and convert reports.
package gtr

import (
	"fmt"
	"strings"
	"time"
)

type Report struct {
	Packages []Package
}

func (r *Report) IsSuccessful() bool {
	for _, pkg := range r.Packages {
		if pkg.BuildError.Name != "" || pkg.RunError.Name != "" {
			return false
		}
		for _, t := range pkg.Tests {
			if t.Result != Pass && t.Result != Skip {
				return false
			}
		}
	}
	return true
}

type Package struct {
	Name       string
	Duration   time.Duration
	Coverage   float64
	Output     []string
	Properties map[string]string

	Tests      []Test
	Benchmarks []Benchmark

	BuildError Error
	RunError   Error
}

func (p *Package) AddProperty(key, value string) {
	if p.Properties == nil {
		p.Properties = make(map[string]string)
	}
	p.Properties[key] = value
}

type Test struct {
	Name     string
	Duration time.Duration
	Result   Result
	Level    int
	Output   []string
}

type Benchmark struct {
	Name        string
	Result      Result
	Output      []string
	Iterations  int64
	NsPerOp     float64
	MBPerSec    float64
	BytesPerOp  int64
	AllocsPerOp int64
}

type Error struct {
	Name     string
	Duration time.Duration
	Cause    string
	Output   []string
}

// FromEvents creates a Report from the given list of events.
// TODO: make packageName optional option
func FromEvents(events []Event, packageName string) Report {
	report := NewReportBuilder(packageName)
	for _, ev := range events {
		switch ev.Type {
		case "run_test":
			report.CreateTest(ev.Name)
		case "pause_test":
			report.PauseTest(ev.Name)
		case "cont_test":
			report.ContinueTest(ev.Name)
		case "end_test":
			report.EndTest(ev.Name, ev.Result, ev.Duration, ev.Indent)
		case "benchmark":
			report.Benchmark(ev.Name, ev.Iterations, ev.NsPerOp, ev.MBPerSec, ev.BytesPerOp, ev.AllocsPerOp)
		case "status":
			report.End()
		case "summary":
			report.CreatePackage(ev.Name, ev.Result, ev.Duration, ev.Data)
		case "coverage":
			report.Coverage(ev.CovPct, ev.CovPackages)
		case "build_output":
			report.CreateBuildError(ev.Name)
		case "output":
			report.AppendOutput(ev.Data)
		default:
			fmt.Printf("unhandled event type: %v\n", ev.Type)
		}
	}
	return report.Build()
}

// TrimPrefixSpaces trims the leading whitespace of the given line using the
// indentation level of the test. Printing logs in a Go test is typically
// prepended by blocks of 4 spaces to align it with the rest of the test
// output. TrimPrefixSpaces intends to only trim the whitespace added by the Go
// test command, without inadvertently trimming whitespace added by the test
// author.
func TrimPrefixSpaces(line string, indent int) string {
	// We only want to trim the whitespace prefix if it was part of the test
	// output. Test output is usually prefixed by a series of 4-space indents,
	// so we'll check for that to decide whether this output was likely to be
	// from a test.
	prefixLen := strings.IndexFunc(line, func(r rune) bool { return r != ' ' })
	if prefixLen%4 == 0 {
		// Use the subtest level to trim a consistenly sized prefix from the
		// output lines.
		for i := 0; i <= indent; i++ {
			line = strings.TrimPrefix(line, "    ")
		}
	}
	return strings.TrimPrefix(line, "\t")
}