Isn't it strange how fishing in minecraft never was given any love? Well I wanted to give it some!
Here is "True Fishing" a missing feature I think mojang should've implemented during early days.

Entities in water (can be configured) will now swim up to the hook if they are within 10 blocks and 30 blocks depth of the hook, nibble a little bit and then take the hook and swim away (during this time you'll have 1.5 seconds to right click and actually hook the fish). Reel in the fish by holding right click!

Mod support (works with most fish types, might work with other entities as well)

To get the extra/vanilla fishing mechanic loot from the entity you'll need to reel it in out of the water, stand next to it and kill it.

Entities will now swim to the hook (based on chance and a timer of 10 seconds).
Entities will nibble or swim away with the hook immediately.
Entities will immitate real life fish struggling and try swim away/around or jump out of water.
Modded entities like orcas from Alex mobs and other mods should work (Some entities like squids etc might not work so well).
Entities in config can spawn nearby if configured.
Right click within 1.5 seconds to hook the fish.
Reel in by clicking or holding right click.
Vanilla fishing loot is enabled by default upon reeled in fish death.
Additional fish drop upon death of a reeled in fish can be configured.

Client side not needed!

Can be used in modpacks.

Fishing rods from other mods will still use the vanilla fishing minigame. A setting later might be made to make all fishing rods use this mod's mechanic.

Planned Features:

Make loot more dynamic by scaling rewards depending on fish strength, endurance and rarity.
Improve AI