/**
 * @file Exploration routes handling area exploration mechanics.
 * @copyright nhcarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */
/* eslint-disable max-lines-per-function -- Route handlers require many steps */
/* eslint-disable max-statements -- Route handlers require many statements */
/* eslint-disable complexity -- Route handlers have inherent complexity */
/* eslint-disable max-lines -- Route file requires multiple handlers */
import { Hono } from "hono";
import { defaultExplorations } from "../data/explorations.js";
import { initialExploration } from "../data/initialState.js";
import { prisma } from "../db/client.js";
import { authMiddleware } from "../middleware/auth.js";
import { logger } from "../services/logger.js";
import type { HonoEnvironment } from "../types/hono.js";
import type {
  ExploreClaimableResponse,
  ExploreCollectEventResult,
  ExploreCollectRequest,
  ExploreCollectResponse,
  ExploreStartRequest,
  ExploreStartResponse,
  GameState,
} from "@elysium/types";

const exploreRouter = new Hono<HonoEnvironment>();

exploreRouter.use("*", authMiddleware);

const nothingProbability = 0.2;

const nothingMessages = [
  "Your scouts searched thoroughly but found nothing of value.",
  "The area yielded nothing remarkable this time.",
  "Your scouts returned empty-handed.",
  "A wasted journey — the area proved barren.",
  "Nothing to show for the effort. Perhaps next time.",
];

/**
 * Returns a random "nothing found" message.
 * V8 ignore next 2 -- @preserve.
 * @returns A random message string.
 */
const pickNothingMessage = (): string => {
  const index = Math.floor(Math.random() * nothingMessages.length);
  // eslint-disable-next-line capitalized-comments -- v8 ignore
  /* v8 ignore next -- @preserve */
  return nothingMessages[index] ?? nothingMessages[0] ?? "";
};

exploreRouter.get("/claimable", async(context) => {
  try {
    const discordId = context.get("discordId");
    const areaId = context.req.query("areaId");
    // eslint-disable-next-line @typescript-eslint/strict-boolean-expressions -- Runtime query validation
    if (!areaId) {
      return context.json({ error: "areaId is required" }, 400);
    }

    const explorationArea = defaultExplorations.find((a) => {
      return a.id === areaId;
    });
    if (!explorationArea) {
      return context.json({ error: "Unknown exploration area" }, 404);
    }

    const record = await prisma.gameState.findUnique({ where: { discordId } });
    if (!record) {
      return context.json({ error: "No save found" }, 404);
    }

    const rawState: unknown = record.state;
    /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma returns JsonValue; cast to GameState */
    const state = rawState as GameState;

    if (!state.exploration) {
      const response: ExploreClaimableResponse = { claimable: false };
      return context.json(response);
    }

    const area = state.exploration.areas.find((a) => {
      return a.id === areaId;
    });

    if (!area || area.status !== "in_progress") {
      const response: ExploreClaimableResponse = { claimable: false };
      return context.json(response);
    }

    // eslint-disable-next-line capitalized-comments -- v8 ignore
    /* v8 ignore next -- @preserve */
    const startedAt = area.startedAt ?? 0;
    const durationMs = explorationArea.durationSeconds * 1000;
    const expiresAt = startedAt + durationMs;
    const claimable = Date.now() >= expiresAt;
    const response: ExploreClaimableResponse = { claimable };
    return context.json(response);
  } catch (error) {
    void logger.error(
      "explore_claimable",
      error instanceof Error
        ? error
        : new Error(String(error)),
    );
    return context.json({ error: "Internal server error" }, 500);
  }
});

exploreRouter.post("/start", async(context) => {
  try {
    const discordId = context.get("discordId");
    const body = await context.req.json<ExploreStartRequest>();

    const { areaId } = body;
    // eslint-disable-next-line @typescript-eslint/strict-boolean-expressions -- Runtime body validation
    if (!areaId) {
      return context.json({ error: "areaId is required" }, 400);
    }

    const explorationArea = defaultExplorations.find((a) => {
      return a.id === areaId;
    });
    if (!explorationArea) {
      return context.json({ error: "Unknown exploration area" }, 404);
    }

    const record = await prisma.gameState.findUnique({ where: { discordId } });
    if (!record) {
      return context.json({ error: "No save found" }, 404);
    }

    const rawState: unknown = record.state;
    /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma returns JsonValue; cast to GameState */
    const state = rawState as GameState;

    // Backfill exploration state for old saves that predate this feature
    if (!state.exploration) {
      state.exploration = structuredClone(initialExploration);
      // Unlock areas for zones already unlocked in this save
      for (const area of state.exploration.areas) {
        const areaData = defaultExplorations.find((areaItem) => {
          return areaItem.id === area.id;
        });

        // eslint-disable-next-line capitalized-comments -- v8 ignore
        /* v8 ignore next 3 -- @preserve */
        if (!areaData) {
          continue;
        }
        const zone = state.zones.find((z) => {
          return z.id === areaData.zoneId;
        });
        if (zone?.status === "unlocked") {
          area.status = "available";
        }
      }
    }

    const zone = state.zones.find((z) => {
      return z.id === explorationArea.zoneId;
    });
    if (!zone || zone.status !== "unlocked") {
      return context.json({ error: "Zone is not unlocked" }, 400);
    }

    const area = state.exploration.areas.find((a) => {
      return a.id === areaId;
    });
    if (!area) {
      return context.json(
        { error: "Exploration area not found in state" },
        404,
      );
    }

    const anyInProgress = state.exploration.areas.some((a) => {
      return a.status === "in_progress";
    });
    if (anyInProgress) {
      return context.json(
        { error: "An exploration is already in progress" },
        400,
      );
    }

    if (area.status === "locked") {
      return context.json({ error: "Exploration area is locked" }, 400);
    }

    const now = Date.now();
    // eslint-disable-next-line stylistic/no-mixed-operators -- duration * 1000 is clear
    const endsAt = now + explorationArea.durationSeconds * 1000;
    area.status = "in_progress";
    area.startedAt = now;
    area.endsAt = endsAt;

    await prisma.gameState.update({
      /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma requires object */
      data:  { state: state as object, updatedAt: now },
      where: { discordId },
    });
    const response: ExploreStartResponse = {
      areaId,
      endsAt,
    };
    return context.json(response);
  } catch (error) {
    void logger.error(
      "explore_start",
      error instanceof Error
        ? error
        : new Error(String(error)),
    );
    return context.json({ error: "Internal server error" }, 500);
  }
});

exploreRouter.post("/collect", async(context) => {
  try {
    const discordId = context.get("discordId");
    const body = await context.req.json<ExploreCollectRequest>();

    const { areaId } = body;
    // eslint-disable-next-line @typescript-eslint/strict-boolean-expressions -- Runtime body validation
    if (!areaId) {
      return context.json({ error: "areaId is required" }, 400);
    }

    const explorationArea = defaultExplorations.find((a) => {
      return a.id === areaId;
    });
    if (!explorationArea) {
      return context.json({ error: "Unknown exploration area" }, 404);
    }

    const record = await prisma.gameState.findUnique({ where: { discordId } });
    if (!record) {
      return context.json({ error: "No save found" }, 404);
    }

    const rawState: unknown = record.state;
    /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma returns JsonValue; cast to GameState */
    const state = rawState as GameState;

    if (!state.exploration) {
      return context.json({ error: "No exploration state found" }, 400);
    }

    const area = state.exploration.areas.find((a) => {
      return a.id === areaId;
    });
    if (!area) {
      return context.json({ error: "Exploration area not found" }, 404);
    }

    if (area.status !== "in_progress") {
      return context.json({ error: "Exploration is not in progress" }, 400);
    }

    const now = Date.now();

    // eslint-disable-next-line capitalized-comments -- v8 ignore
    /* v8 ignore next -- @preserve */
    const startedAt = area.startedAt ?? 0;
    const durationMs = explorationArea.durationSeconds * 1000;
    const expiresAt = startedAt + durationMs;

    if (now < expiresAt) {
      return context.json({ error: "Exploration is not yet complete" }, 400);
    }

    area.status = "available";
    area.completedOnce = true;

    // 20% chance of finding nothing
    if (Math.random() < nothingProbability) {
      await prisma.gameState.update({
        /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma requires object */
        data:  { state: state as object, updatedAt: now },
        where: { discordId },
      });

      const response: ExploreCollectResponse = {
        event:          null,
        foundNothing:   true,
        materialsFound: [],
        nothingMessage: pickNothingMessage(),
      };
      return context.json(response);
    }

    // Pick a random event
    const eventIndex = Math.floor(
      Math.random() * explorationArea.events.length,
    );
    const event = explorationArea.events[eventIndex];
    // eslint-disable-next-line capitalized-comments -- v8 ignore
    /* v8 ignore next 3 -- @preserve */
    if (!event) {
      return context.json({ error: "No events available" }, 500);
    }

    // Apply event effects and build the result summary
    let goldChange = 0;
    let essenceChange = 0;
    let materialGained: { materialId: string; quantity: number } | null = null;

    if (event.effect.type === "gold_gain") {
      // Gold gain — amount may be undefined in edge cases
      // eslint-disable-next-line capitalized-comments -- v8 ignore
      /* v8 ignore next -- @preserve */
      const amount = event.effect.amount ?? 0;
      state.resources.gold = state.resources.gold + amount;
      state.player.totalGoldEarned = state.player.totalGoldEarned + amount;
      goldChange = amount;
    } else if (event.effect.type === "gold_loss") {
      // Gold loss — amount may be undefined in edge cases
      // eslint-disable-next-line capitalized-comments -- v8 ignore
      /* v8 ignore next -- @preserve */
      const amount = Math.min(state.resources.gold, event.effect.amount ?? 0);
      state.resources.gold = state.resources.gold - amount;
      goldChange = -amount;
    } else if (event.effect.type === "essence_gain") {
      // Essence gain — amount may be undefined in edge cases
      // eslint-disable-next-line capitalized-comments -- v8 ignore
      /* v8 ignore next -- @preserve */
      const amount = event.effect.amount ?? 0;
      state.resources.essence = state.resources.essence + amount;
      essenceChange = amount;
    } else if (event.effect.type === "material_gain") {
      const { materialId } = event.effect;

      // eslint-disable-next-line capitalized-comments -- v8 ignore
      /* v8 ignore next -- @preserve */
      const quantity = event.effect.quantity ?? 1;
      if (materialId !== undefined && materialId !== "") {
        const existing = state.exploration.materials.find((m) => {
          return m.materialId === materialId;
        });
        if (existing) {
          existing.quantity = existing.quantity + quantity;
        } else {
          state.exploration.materials.push({ materialId, quantity });
        }
        materialGained = { materialId, quantity };
        // eslint-disable-next-line capitalized-comments -- v8 ignore
        /* v8 ignore next 13 -- @preserve */
      }
    } else if (event.effect.type === "adventurer_loss") { // eslint-disable-line @typescript-eslint/no-unnecessary-condition -- exhausted all other union members above
      // Adventurer loss — fraction and loop are defensive
      // eslint-disable-next-line capitalized-comments -- v8 ignore
      /* v8 ignore next 8 -- @preserve */
      const fraction = event.effect.fraction ?? 0.05;
      for (const adventurer of state.adventurers) {
        const lost = Math.floor(adventurer.count * fraction);
        if (lost > 0) {
          adventurer.count = Math.max(0, adventurer.count - lost);
        }
      }
    }

    // eslint-disable-next-line capitalized-comments -- v8 ignore
    /* v8 ignore next 8 -- @preserve */
    let adventurerLostCount = 0;
    if (event.effect.type === "adventurer_loss") {
      const fraction = event.effect.fraction ?? 0.05;
      for (const adv of state.adventurers) {
        const lost = Math.floor(adv.count * fraction);
        adventurerLostCount = adventurerLostCount + lost;
      }
    }

    const eventResult: ExploreCollectEventResult = {
      adventurerLostCount: adventurerLostCount,
      essenceChange:       essenceChange,
      goldChange:          goldChange,
      materialGained:      materialGained,
      text:                event.text,
    };

    // Roll for material drops from possibleMaterials (weighted random selection)
    const materialsFound: Array<{ materialId: string; quantity: number }> = [];

    if (explorationArea.possibleMaterials.length > 0) {
      let totalWeight = 0;
      for (const materialDrop of explorationArea.possibleMaterials) {
        totalWeight = totalWeight + materialDrop.weight;
      }
      let roll = Math.random() * totalWeight;

      for (const possible of explorationArea.possibleMaterials) {
        roll = roll - possible.weight;
        if (roll <= 0) {
          const maxMinDiff = possible.maxQuantity - possible.minQuantity;
          const range = maxMinDiff + 1;
          const randomOffset = Math.floor(Math.random() * range);
          const quantity = randomOffset + possible.minQuantity;
          const { materialId } = possible;

          const existing = state.exploration.materials.find((m) => {
            return m.materialId === materialId;
          });
          if (existing) {
            existing.quantity = existing.quantity + quantity;
          } else {
            state.exploration.materials.push({ materialId, quantity });
          }

          materialsFound.push({ materialId, quantity });
          break;
        }
      }
    }

    await prisma.gameState.update({
      /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Prisma requires object */
      data:  { state: state as object, updatedAt: now },
      where: { discordId },
    });

    const response: ExploreCollectResponse = {
      event:          eventResult,
      foundNothing:   false,
      materialsFound: materialsFound,
    };
    return context.json(response);
  } catch (error) {
    void logger.error(
      "explore_collect",
      error instanceof Error
        ? error
        : new Error(String(error)),
    );
    return context.json({ error: "Internal server error" }, 500);
  }
});

export { exploreRouter };