package provenance

import (
	"sort"

	distreference "github.com/docker/distribution/reference"
	resourcestypes "github.com/moby/buildkit/executor/resources/types"
	"github.com/moby/buildkit/solver/result"
	"github.com/moby/buildkit/util/urlutil"
	digest "github.com/opencontainers/go-digest"
	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
)

type Result = result.Result[*Capture]

type ImageSource struct {
	Ref      string
	Platform *ocispecs.Platform
	Digest   digest.Digest
	Local    bool
}

type GitSource struct {
	URL    string
	Commit string
}

type HTTPSource struct {
	URL    string
	Digest digest.Digest
}

type LocalSource struct {
	Name string `json:"name"`
}

type Secret struct {
	ID       string `json:"id"`
	Optional bool   `json:"optional,omitempty"`
}

type SSH struct {
	ID       string `json:"id"`
	Optional bool   `json:"optional,omitempty"`
}

type Sources struct {
	Images []ImageSource
	Git    []GitSource
	HTTP   []HTTPSource
	Local  []LocalSource
}

type Capture struct {
	Frontend            string
	Args                map[string]string
	Sources             Sources
	Secrets             []Secret
	SSH                 []SSH
	NetworkAccess       bool
	IncompleteMaterials bool
	Samples             map[digest.Digest]*resourcestypes.Samples
}

func (c *Capture) Merge(c2 *Capture) error {
	if c2 == nil {
		return nil
	}
	for _, i := range c2.Sources.Images {
		c.AddImage(i)
	}
	for _, l := range c2.Sources.Local {
		c.AddLocal(l)
	}
	for _, g := range c2.Sources.Git {
		c.AddGit(g)
	}
	for _, h := range c2.Sources.HTTP {
		c.AddHTTP(h)
	}
	for _, s := range c2.Secrets {
		c.AddSecret(s)
	}
	for _, s := range c2.SSH {
		c.AddSSH(s)
	}
	if c2.NetworkAccess {
		c.NetworkAccess = true
	}
	if c2.IncompleteMaterials {
		c.IncompleteMaterials = true
	}
	return nil
}

func (c *Capture) Sort() {
	sort.Slice(c.Sources.Images, func(i, j int) bool {
		return c.Sources.Images[i].Ref < c.Sources.Images[j].Ref
	})
	sort.Slice(c.Sources.Local, func(i, j int) bool {
		return c.Sources.Local[i].Name < c.Sources.Local[j].Name
	})
	sort.Slice(c.Sources.Git, func(i, j int) bool {
		return c.Sources.Git[i].URL < c.Sources.Git[j].URL
	})
	sort.Slice(c.Sources.HTTP, func(i, j int) bool {
		return c.Sources.HTTP[i].URL < c.Sources.HTTP[j].URL
	})
	sort.Slice(c.Secrets, func(i, j int) bool {
		return c.Secrets[i].ID < c.Secrets[j].ID
	})
	sort.Slice(c.SSH, func(i, j int) bool {
		return c.SSH[i].ID < c.SSH[j].ID
	})
}

// OptimizeImageSources filters out image sources by digest reference if same digest
// is already present by a tag reference.
func (c *Capture) OptimizeImageSources() error {
	m := map[string]struct{}{}
	for _, i := range c.Sources.Images {
		ref, nameTag, err := parseRefName(i.Ref)
		if err != nil {
			return err
		}
		if _, ok := ref.(distreference.Canonical); !ok {
			m[nameTag] = struct{}{}
		}
	}

	images := make([]ImageSource, 0, len(c.Sources.Images))
	for _, i := range c.Sources.Images {
		ref, nameTag, err := parseRefName(i.Ref)
		if err != nil {
			return err
		}
		if _, ok := ref.(distreference.Canonical); ok {
			if _, ok := m[nameTag]; ok {
				continue
			}
		}
		images = append(images, i)
	}
	c.Sources.Images = images
	return nil
}

func (c *Capture) AddImage(i ImageSource) {
	for _, v := range c.Sources.Images {
		if v.Ref == i.Ref && v.Local == i.Local {
			if v.Platform == i.Platform {
				return
			}
			if v.Platform != nil && i.Platform != nil {
				if v.Platform.Architecture == i.Platform.Architecture && v.Platform.OS == i.Platform.OS && v.Platform.Variant == i.Platform.Variant {
					return
				}
			}
		}
	}
	c.Sources.Images = append(c.Sources.Images, i)
}

func (c *Capture) AddLocal(l LocalSource) {
	for _, v := range c.Sources.Local {
		if v.Name == l.Name {
			return
		}
	}
	c.Sources.Local = append(c.Sources.Local, l)
}

func (c *Capture) AddGit(g GitSource) {
	g.URL = urlutil.RedactCredentials(g.URL)
	for _, v := range c.Sources.Git {
		if v.URL == g.URL {
			return
		}
	}
	c.Sources.Git = append(c.Sources.Git, g)
}

func (c *Capture) AddHTTP(h HTTPSource) {
	h.URL = urlutil.RedactCredentials(h.URL)
	for _, v := range c.Sources.HTTP {
		if v.URL == h.URL {
			return
		}
	}
	c.Sources.HTTP = append(c.Sources.HTTP, h)
}

func (c *Capture) AddSecret(s Secret) {
	for i, v := range c.Secrets {
		if v.ID == s.ID {
			if !s.Optional {
				c.Secrets[i].Optional = false
			}
			return
		}
	}
	c.Secrets = append(c.Secrets, s)
}

func (c *Capture) AddSSH(s SSH) {
	if s.ID == "" {
		s.ID = "default"
	}
	for i, v := range c.SSH {
		if v.ID == s.ID {
			if !s.Optional {
				c.SSH[i].Optional = false
			}
			return
		}
	}
	c.SSH = append(c.SSH, s)
}

func (c *Capture) AddSamples(dgst digest.Digest, samples *resourcestypes.Samples) {
	if c.Samples == nil {
		c.Samples = map[digest.Digest]*resourcestypes.Samples{}
	}
	c.Samples[dgst] = samples
}

func parseRefName(s string) (distreference.Named, string, error) {
	ref, err := distreference.ParseNormalizedNamed(s)
	if err != nil {
		return nil, "", err
	}
	name := ref.Name()
	tag := "latest"
	if r, ok := ref.(distreference.Tagged); ok {
		tag = r.Tag()
	}
	return ref, name + ":" + tag, nil
}