package firstview

import (
	"context"
	"strconv"

	"git.novox.be/novox/mesh-delivery/contracts/go/clients/meshcatalogclient"
	catalogseat "git.novox.be/novox/mesh-delivery/contracts/go/seats/meshcatalog"
	"git.novox.be/novox/mesh-sdk/go/seatdef"

	"github.com/novox/mesh-tools/node-tools/internal/approval"
)

// Findings is the runner's held finding writer, the one the gate writes its findings through too (design 46 7-approval-mark
// §4, §16, §19); nil when it was not made.
func (v *Views) Findings() approval.FindingWriter {
	if v.deps.Findings == nil {
		return nil
	}
	return v.deps.Findings
}

// ApprovalCatalog is the catalog half as the gate reads its marks (design 46 7-approval-mark §5): the entries the branch
// follower holds, an entry by fingerprint asked of `mesh-catalog.entry` when no branch lists it, and the seat definitions
// the seat list holds (defs).
func (v *Views) ApprovalCatalog(defs func() map[string]seatdef.Definition) approval.Catalog {
	return approvalCatalog{v: v, defs: defs}
}

type approvalCatalog struct {
	v    *Views
	defs func() map[string]seatdef.Definition
}

func (c approvalCatalog) Ready() error {
	if c.v.branches == nil {
		return errNotFollowed
	}
	return c.v.branches.Ready()
}

func (c approvalCatalog) Revision() string {
	if c.v.branches == nil {
		return ""
	}
	for _, branch := range c.v.branches.Followed() {
		if cat, ok := c.v.branches.Catalog(branch); ok {
			if half, ok := cat.View(); ok {
				return strconv.FormatInt(half.Revision.Revision, 10)
			}
		}
	}
	return ""
}

func (c approvalCatalog) Served(fingerprint string) (catalogseat.CatalogEntry, bool, string) {
	if c.v.branches == nil {
		return catalogseat.CatalogEntry{}, false, errNotFollowed.Error()
	}
	e, state := c.v.branches.Resolve(context.Background(), fingerprint)
	return e, state == meshcatalogclient.EntryAnswered, string(state)
}

func (c approvalCatalog) Newest(module string) (catalogseat.CatalogEntry, bool) {
	if c.v.branches == nil {
		return catalogseat.CatalogEntry{}, false
	}
	e, ok, err := c.v.branches.Entry(module)
	return e, ok && err == nil
}

func (c approvalCatalog) Definitions() map[string]seatdef.Definition {
	if c.defs == nil {
		return nil
	}
	return c.defs()
}

type notFollowed struct{}

func (notFollowed) Error() string { return "the catalog half is not followed by this runner" }

var errNotFollowed error = notFollowed{}